# VW LT doka with Nissan leaf



## Kevin Sharpe (Jul 4, 2011)

Very cool


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## brian_ (Feb 7, 2017)

I see that you've switched from the earlier plan of adapting the original LT rear suspension into a deDion, to using a trailing-arm or semi-trailing arm independent suspension (presumably from a T4 Syncro). As long as all of the bits have enough capacity for this heavier truck, this seems like a good plan to me. 

Usually clearance between the suspension arms and the front of the Leaf motor would be a concern, but presumably in this case the extra width of the LT moves the arms apart enough to provide enough room.

It looks like the arms are entirely outboard of the subframe rails, the Leaf drive unit is entirely inboard, and the rails are parallel and equidistant from the vehicle centre line. Since the Leaf unit is normally offset to the right-hand side of the vehicle (with the long motor to the right, the short transmission to the left, and the plane between them about centred, placing the diff about on centre) either

the Leaf unit is offset to the right in the subframe, or
the Leaf unit is about centred, in the subframe, so shifted left of where it would be in the Leaf.
Which way did you go? It looks like #2.

Assuming that the diff is now left of centre, either

the right-side halfshaft is longer than the left, or
the Leaf has unequal-length halfshafts, despite have a roughly centred differential.

The photos are great, but it's a little hard to judge dimensions from them.


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## Tony Bogs (Apr 12, 2014)

Very interesting. A van and a Leaf transplant. That could very well be the only road to a DIY EV for me (regulatory barriers).
The Nissan NV200 is a bit too small (and new).

The driveshafts? Are they a direct fit? Seems unlikely, maybe custom made?


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## brian_ (Feb 7, 2017)

Tony Bogs said:


> Very interesting. A van and a Leaf transplant. That could very well be the only road to a DIY EV for me (regulatory barriers).


This LT is a truck with a tray bed, not an enclosed van, but many are vans and either way it is a commercial vehicle. Tony, I assume that you mean that regulations would be easier to work with for a commercial vehicle, right?



Tony Bogs said:


> The driveshafts? Are they a direct fit? Seems unlikely, maybe custom made?


I'm interested in the details, but they're clearly not directly from either an LT or the Leaf. The LT doesn't have an independent rear suspension, and the Leaf (aside from not having similar hardware on the wheel end as the VW pieces being used) is much narrower than the LT. The front track of a 2017 Leaf is 1,540 mm (61″), while the LT is 2.085 m (6 ft 10.1 in) wide at the cab and 2.14 m (7 ft 0.3 in) at the flatbed, so the track must be substantial.


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## Tony Bogs (Apr 12, 2014)

I need a van with an elevator for a wheelchair in the back as my future means of transport. 
Electric of course.
Because of strict regulations for the electrical parts I want use components and systems that have been declared road legal as part as a type approval. 
Transplanting a drivetrain and the electrical system from a Leaf into an older type van (like a VW up to '91) with an elevator already fitted, seems to be the best option. 
There are a lot of Leafs on the road and they're affordable.

So I'm very interested to see how this conversion goes. For instance the driveshafts. Apparently, they don't pose a big problem for the TS, but I'm very curious how he solved it, since they are clearly not from the donor cars.


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## brian_ (Feb 7, 2017)

Tony Bogs said:


> I need a van with an elevator for a wheelchair in the back as my future means of transport.
> Electric of course.
> Because of strict regulations for the electrical parts I want use components and systems that have been declared road legal as part as a type approval.
> Transplanting a drivetrain and the electrical system from a Leaf into an older type van (like a VW up to '91) with an elevator already fitted, seems to be the best option.


That makes sense. The easiest fit into a third-generation Transporter (T3) might be a small Tesla Model S/X drive unit, because that motor sits behind the axle like the VW engine - the Leaf wouldn't fit with the T3 suspension and structure because it sits ahead of the axle line. The LT has lots of room to work with and the suspension is being completely replaced, but something like a T3 doesn't have that kind of space, and replacing the whole suspension doesn't seem like a good route for easy approval in a highly regulated country.

Fitting an entire Tesla battery pack into a VW van is another matter. See Kevin's "ICE Breaker" project (Tesla drive unit into T1) for one example (of a small drive drive unit, and 3/4 of the battery modules), but note that a complete change in suspension shouldn't be necessary (especially in a T3).

One challenge with the complete powertrain from a production EV is that the system doesn't want to run with critical parts missing, which is likely to be the case. The approach used by some people is to replace the controller with one which they can program, but you would need to check if that meets the approval requirements.

On the other hand, a Leaf (or VW e-Golf) drive unit would fit in the front of a T4, fitting very much like the original transverse engine. There would still be the challenges of fitting in the battery, and making the control electronics work.



Tony Bogs said:


> So I'm very interested to see how this conversion goes. For instance the driveshafts. Apparently, they don't pose a big problem for the TS, but I'm very curious how he solved it, since they are clearly not from the donor cars.


In addition to this project, Kevin's project and others have described building halfshafts which fit the drive unit one end and the base vehicle's hubs on the other end.


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## Tony Bogs (Apr 12, 2014)

Spot on, Brian. For my own safety and the safety of others on the road, it is much better to pick an EV from the well engineered and tested commercially available ones.


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## Kevin Sharpe (Jul 4, 2011)

seen this?


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## brian_ (Feb 7, 2017)

Kevin Sharpe said:


> seen this?
> 
> VW Pickup with Nissan Leaf Motor install part 1


Although he hasn't really started the installation yet - it's really just a positioning mock-up... yes, that's the arrangement I was suggesting for a T4.

Of course, this is very different vehicle and installation from CanadaLT28's project... can we get back to that?


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## CanadaLT28 (Oct 15, 2011)

Sorry for not getting back quickly. Anyway, yes, the arms are from a 2002 T4. The ones I originally had were from a 1992 but they were drums and I really wanted discs, and the Leaf needs ABS which is only on the disc brake models. The shafts are OEM T4 units which I cut (bloody hard stuff) and I have a thick wall DOM steel which I have bored out to lengthen them. The final length is not determined yet but they are "slightly" different in length but probably not by more than 25mm so I guess you could say the motor is mounted roughly in the middle.

Due to the differences in the mounting under the LT, I decided to make it a complete unit with all shock and spring mounts as part of the sub frame. I have just received air bags which will help a lot in figuring out the ride height.

Tony, I would be really interested in putting a Leaf drivetrain into a T3. There is a DOKA with a Tesla motor in the USA but I think it would be pretty easy to mount the complete Leaf system in there. The rear deck would come up a bit and one would have to make room for the batteries but the T3 is so great a vehicle, it would be worth doing. I assume you are in the UK.


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## CanadaLT28 (Oct 15, 2011)

brian_ said:


> I see that you've switched from the earlier plan of adapting the original LT rear suspension into a deDion, to using a trailing-arm or semi-trailing arm independent suspension (presumably from a T4 Syncro). As long as all of the bits have enough capacity for this heavier truck, this seems like a good plan to me.
> 
> 
> The photos are great, but it's a little hard to judge dimensions from them.


Interesting thing about the T4, the rear hubs contain the same spline as the Syncro so all I had to do was pull out the blanking plate. It was a bit confusing at first because the ABS ring is not on the shaft but as part of a cup that fits into the hub (pics below). I machined the cup to allow the spline to go through to the hub, thereby keeping the ring.


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## CanadaLT28 (Oct 15, 2011)

Here is a pic of a T4 with the air bags from someone else motorhome. I will be doing the same thing. Although it is a drum, the blanking plate is the same on the disc model, except for the ABS ring.


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## CanadaLT28 (Oct 15, 2011)

Tony Bogs said:


> So I'm very interested to see how this conversion goes. For instance the driveshafts. Apparently, they don't pose a big problem for the TS, but I'm very curious how he solved it, since they are clearly not from the donor cars.


I did get the Nissan shafts which I disassembled to give me only the, hard to copy, spline for the Leaf output. I then welded flanges onto it to make adapters that will take a standard VW T4 shaft. It wasn't as difficult as it may seem.


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## CanadaLT28 (Oct 15, 2011)

A little beginning for the air bag supports. The bottom clamp will have a 10deg or so bevel to take some stress out of the rubber.


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## brian_ (Feb 7, 2017)

CanadaLT28 said:


> A little beginning for the air bag supports. The bottom clamp will have a 10deg or so bevel to take some stress out of the rubber.


Good - I've seen some terrible air spring mounting jobs, and it's good to see you doing it properly. Presumably this will place the end plates aligned and approximately parallel at full compression.


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## CanadaLT28 (Oct 15, 2011)

Little bit at a time.


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## CanadaLT28 (Oct 15, 2011)

The bracket can be seen having a different angle to the support. The setup will have a much lesser angle when the weight is on it but it seems there is no way to eliminate it totally.


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## brian_ (Feb 7, 2017)

CanadaLT28 said:


> The bracket can be seen having a different angle to the support. The setup will have a much lesser angle when the weight is on it but it seems there is no way to eliminate it totally.


The best that you can do with a single-arm suspension like this is to have the end plates parallel at one specific height. The best compromise might not put that at the normal ride height, because it is probably more important to avoid damage at the extremes of suspension travel.

The other solution is to mount the air spring on a telescopic cylinder (normally a shock absorber) with the angle change taken up by the mounts at the ends of the shock, but the T4 arms are not designed for that... and most air spring don't use that setup, and don't have problems.


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## CanadaLT28 (Oct 15, 2011)

Yea, I thought about something like a "bag over shock" at one point and I will be putting them on the front as a spring replacement. I need a 2" lift as well.

I think it will work out well. Right now I am troubled by the lack of Leaf battery packs out there at the wreckers. If I can't find one, I will be forced to buy a couple Volt packs (or equivalent) and figure out how to make the Nissan controllers listen to some foreign sensors. That is a tall order for me. I am no good at that stuff. I need to build battery boxes which will be hard to do without the cells.


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## CanadaLT28 (Oct 15, 2011)

I'll post this somewhere else If I must. I can't remember if I asked this question before but, as I am having a hard time getting a Leaf battery pack, I am looking at getting 2+ Volt packs and using them but the issue is, how does the leaf BMS recognize a bespoke battery pack? What do I need to do to get it to communicate?


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## Kevin Sharpe (Jul 4, 2011)

CanadaLT28 said:


> how does the leaf BMS recognize a bespoke battery pack?


By default the Leaf BMS will only work with Leaf modules. If you change the chemistry (i.e. use a Volt pack) it's very unlikely the BMS will work.

Obviously you could reprogram the Leaf BMS firmware (as Wolf has done) but I think that is beyond most peoples knowledge and budget. Possibly an alternative path would be to commission Wolf to provide a CAN emulator that makes the Volt Battery 'look like' a Leaf Battery. I think the Volt BMS must have been hacked by now.



CanadaLT28 said:


> What do I need to do to get it to communicate?


Reverse Enginnering the Nissan Leaf BMS Serial Protocol...


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## CanadaLT28 (Oct 15, 2011)

If I remember correctly, Wolf said he wasn't ready with his system yet so who knows how well it works. 



Volt packs are generally around $1200-1500 and leaf packs are more than double.


I would expect that both packs have been hacked by now. Enough people have eluded to it over the last few years but I just can't keep track of all the goings on.


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## CanadaLT28 (Oct 15, 2011)

WooHoo, I can see my thread again.


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## CanadaLT28 (Oct 15, 2011)

OK folks. I now have both a leaf pack and one volt pack. I would like opinions on whether to leave the leaf pack in its case and put the volt pack in custom battery boxes that fit the truck better OR take them all apart and attempt to merge them in such a way as to have cells work in parallel. I will get another volt pack if needed to make it work.

I will also see what Wolf has up his sleeve. Damian appears to have also done some magic with the volt BMS, or so I am told. 

I'm hoping toget this right the first time, lol (fat chance, but I can hope)


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## brian_ (Feb 7, 2017)

CanadaLT28 said:


> I now have both a leaf pack and one volt pack. I would like opinions on whether to leave the leaf pack in its case and put the volt pack in custom battery boxes that fit the truck better OR take them all apart and attempt to merge them in such a way as to have cells work in parallel.


I'm not sure that I understand both alternatives.

Is the first option to parallel the entire Leaf pack (96S2P of 33 Ah cells) with the entire Volt pack? They have about the same nominal voltage, but different capacities and seem unlikely to load-share ideally. Or is the first option to use one at a time, switching between them?

Is the second option to reconfigure the Leaf pack to place modules in parallel and then series them into a 48S set, and reconfigure the Volt pack to put modules or more cells in parallel and then series them into another 48S set, then put all of that in series? With the different capacities this seems like a problematic configuration. Or, is the second option to parallel two Leaf cells with a set (3 if the earlier Volt pack, 2 if the later Volt pack) of Volt cells, then put those mixed-source groups in series?

Modules are easy to connect in parallel with other modules, but the Volt modules are big (lots of cells) so it doesn't get even close to cell level parallel connections. Reconfiguring Volt modules at the cell level requires cutting of welds and making some sort of clamped connections. The Leaf modules are only 2S, and because they have a "middle" terminal for the BMS they can be paralleled at the cell level with only bolted connections. But I'm guessing that you already know that...


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## CanadaLT28 (Oct 15, 2011)

brian_ said:


> I'm not sure that I understand both alternatives.
> 
> Is the first option to parallel the entire Leaf pack (96S2P of 33 Ah cells) with the entire Volt pack? They have about the same nominal voltage, but different capacities and seem unlikely to load-share ideally. Or is the first option to use one at a time, switching between them?
> 
> ...



I should not be speaking in terms of cell level. My mistake.


I do know that there is a "middle terminal" for the BMS on Leaf modules and the first thought I had (and I don't know how realistic this is) would be to take X number of leaf modules and combine them with X number of Volt modules to make one larger grouping which could allow me to use only the Leaf BMS, and then S and P the groups to get the proper output voltage.


The Leaf is a 2014 pack as is the current Volt pack. The second option would be to get another Volt pack and try to make 1 pack of equal capacity to the Leaf pack and put it parallel with the leaf pack. The ultimate goal is to be able to use just one charger.


If there is a 3rd option I am all ears.


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## brian_ (Feb 7, 2017)

CanadaLT28 said:


> I should not be speaking in terms of cell level...
> 
> I do know that there is a "middle terminal" for the BMS on Leaf modules and the first thought I had (and I don't know how realistic this is) would be to take X number of leaf modules and combine them with X number of Volt modules to make one larger grouping which could allow me to use only the Leaf BMS, and then S and P the groups to get the proper output voltage.


Thanks, that's more clear - it's essentially the mixed-source groups that I listed last, but connected only at the module level.

All Leaf modules are 2S. There are glued-together module pairs to the later packs, but you can still make the electrical connection at the single module level. Gen 1 Volt modules are 6S and (mostly) 12S; Gen 2 Volt modules are 12S and 16S... so each Volt module could be paralleled with a suitable number of Leaf modules.

My concern with this would be that with no connection between the cell-level connections of the Leaf BMS and the corresponding points in Volt pack, there would be no monitoring of any imbalance in the Volt pack; one cell group in the Volt pack could be charged too high or discharged too low and the Leaf BMS would not be able to warn about it. Of course there would also be no balancing of the Volt pack (maybe okay - that's a whole argument of it's own), and if the Leaf BMS balances the Leaf modules then those Leaf modules would be discharged a bit below the Volt module in parallel with them.


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## CanadaLT28 (Oct 15, 2011)

Lots of thought on this. If using Volt packs, I can get 3 of them in 3 rows under the truck easily and they are a LOT easier to come by than the Leaf packs. All that is needed is some way to communicate with Leaf brain. Using the Volt pack also gives me more confidence in the SOH of the batteries as they have not generally been abused. 



The leaf can become powerwall.


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## Duncan (Dec 8, 2008)

Do the Leaf and the Volt use the same chemistry?

I would be surprised if it was exactly the same - so they will have different charge/voltage curves

Connecting them at cell level would be a disaster


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## brian_ (Feb 7, 2017)

Duncan said:


> Do the Leaf and the Volt use the same chemistry?


The Volt (both generations) use "NMC-LMO Pouch" cells (by LG)
The Leaf was (at least originally) LiMn2O4 (LMO) with LiNiO2... no NMC.

No, the two are not matched. They are different chemistry choices to suit different performance requirements and different cooling systems.

I agree that this is another reason not to mix cells from both sources in parallel.


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## CanadaLT28 (Oct 15, 2011)

Sorry if I misspoke, I will not be using the Leaf batteries in truck at all, just the volt packs (3 if I can get them). I will use the Volt charger and BMS so that will be somewhat stand.
Obviously the Leaf control is fine for the motor and inputs but it will probably get confused with the batteries so what can I do there? I know people have done this before but I haven't found a "part that I can buy" to mesh the Leaf controller and Volt batteries/BMS


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## CanadaLT28 (Oct 15, 2011)

A few updates. I have sourced the complete front end for a T4 (Eurovan) and will be using it to put a second leaf motor (motor/inverter/charger/dc-dc etc) in the front as a front drive truck. I will still use the current motor and inverter on the back as is but only the motor and inverter. 

This will give me a 4x4 capability. Oddly, the T4 suspension is rated as high as my LT suspension and with shock/bags, I can get a better capacity. 

I have just bought Pauls board that allows me to configure the Leaf to be controlled as I wish. There is a lot about it that I don't know such as how I will interface with the Volt pack(s). There is currently no DC fast charge on this leaf and I want to put one on if possible.

Paul believes that I can just split the throttle signal between the two inverters as they are torque controlled motors. It remains to be seen if I can run the two inverters with one controller. 



Any thoughts will be appreciated, of course.


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## Tony Bogs (Apr 12, 2014)

Thanks for the pictures of the modified drive shafts.


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## mainfuse (Jun 9, 2016)

Hi , new to this thread, we have put together a geo metro with a 2013 leaf drive train, using our vcu to control the CAN messages that run the inverter. I would like to get photos of builds that others are doing with these cheap leaf drives. we have plans to put one in a ski boat ,and a two motor 4wheel drive vehicle. up next will be my MAzda Miata. I am working on mating the motor to the transmission now. Clutch or no clutch is my question .thunderstruck motors
thanks Brian


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## CanadaLT28 (Oct 15, 2011)

mainfuse said:


> Hi , new to this thread, we have put together a geo metro with a 2013 leaf drive train, using our vcu to control the CAN messages that run the inverter. I would like to get photos of builds that others are doing with these cheap leaf drives. we have plans to put one in a ski boat ,and a two motor 4wheel drive vehicle. up next will be my MAzda Miata. I am working on mating the motor to the transmission now. Clutch or no clutch is my question .thunderstruck motors
> thanks Brian



Where are you Brian?


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## mainfuse (Jun 9, 2016)

Santa Rosa, CAlif.
thunderstruck-ev.com


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## CanadaLT28 (Oct 15, 2011)

Ahh, I didn't see that link. In my case I am doing 4WD by using two complete Leaf drivetrains so I have no need for the clutch. Can't help you there.


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## dbargaehr (Nov 4, 2018)

CanadaLT28 said:


> Ahh, I didn't see that link. In my case I am doing 4WD by using two complete Leaf drivetrains so I have no need for the clutch. Can't help you there.


Hi,

looking at using a leaf drive in my conversion. Any chance you can provide the dimensions on the motor case length? (and ideally the motor case diameter too)?

Also curious if you're integrating the Leaf's liquid cooling with the existing radiator, or doing something else entirely. I've subscribed to this thread, really excited to see how it turns out.


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## CanadaLT28 (Oct 15, 2011)

dbargaehr said:


> Hi,
> 
> looking at using a leaf drive in my conversion. Any chance you can provide the dimensions on the motor case length? (and ideally the motor case diameter too)?
> 
> Also curious if you're integrating the Leaf's liquid cooling with the existing radiator, or doing something else entirely. I've subscribed to this thread, really excited to see how it turns out.



I don't have the dimensions off hand but they are available somewhere on the tinterweb. I wil be using a VW passat rad (because I already have it) to cool the motors/inverters and to provide cooling to the Volt batteries. I have a separate heater to heat the batteries if needed.


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## dbargaehr (Nov 4, 2018)

CanadaLT28 said:


> dbargaehr said:
> 
> 
> > Hi,
> ...


Thanks. I’m curious about the motor dims because the ones I’ve found don’t specify if it’s the 2011-2012 motor or 2013-2017 motor, and Everything I’ve found includes the motor AND inverter/controller. 

I like the idea of recycling the existing radiator system. 

Really looking forward to seeing how this conversion turns out.


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## mainfuse (Jun 9, 2016)

we are just using the heater core to cool the motor /inverter. seems to work fine even on hot California days in the summer


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## CanadaLT28 (Oct 15, 2011)

dbargaehr said:


> Thanks. I’m curious about the motor dims because the ones I’ve found don’t specify if it’s the 2011-2012 motor or 2013-2017 motor, and Everything I’ve found includes the motor AND inverter/controller.
> 
> I like the idea of recycling the existing radiator system.
> 
> Really looking forward to seeing how this conversion turns out.



The 2011/12 is completely different from the later ones (mine are 2013) and practically all the major components are in the smooth curved top. The 2012 has a top with horizontal ribs. 



Hopefully the people selling have at least a picture of the unit. I think the motor is the same for all years but charger and dc-dc converter is not. I don't know if this helps at all. This one is a 2013 in the video. https://www.youtube.com/watch?v=4GG3QRPGlPc&t=317s


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## CanadaLT28 (Oct 15, 2011)

Just small steps. Now I have the 2nd of perhaps 4 Volt packs. Still on the lookout for more at a good price.
More stripping of the old LT to get it ready for the cab to come off. It's hard to work outside when it's -10C out, LOL


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## CanadaLT28 (Oct 15, 2011)

Well Folks, the project is on. I have decided to start with a new frame which is designed to hold 4 Volt packs (hopefully I will be able to get double the range from the same weight in a few years). I am now in the process of locating the suspension points on the rear. The bag on the suspension is just outside of the connection between the rails and rear cross member so it should be plenty strong when I get the gussets welded on.


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## dbargaehr (Nov 4, 2018)

CanadaLT28 said:


> Well Folks, the project is on. I have decided to start with a new frame which is designed to hold 4 Volt packs (hopefully I will be able to get double the range from the same weight in a few years). I am now in the process of locating the suspension points on the rear. The bag on the suspension is just outside of the connection between the rails and rear cross member so it should be plenty strong when I get the gussets welded on.


Awesome! 

Are you finding that salvage EV packs are becoming more and more popular? I feel like as i've watched auto auction sites there seems to be slightly more interest.


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## CanadaLT28 (Oct 15, 2011)

Now to make the T4 suspension mount properly to the new frame. There is lots of room for the Leaf motor under the dog house in front of the suspension.


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## brian_ (Feb 7, 2017)

This is all looking good. 

... but at this point, all that is being used of the LT is the cab, right? It's basically a fully custom built truck, using a variety of production components from multiple sources, one of which is a VW LT cab.


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## CanadaLT28 (Oct 15, 2011)

brian_ said:


> This is all looking good.
> 
> ... but at this point, all that is being used of the LT is the cab, right? It's basically a fully custom built truck, using a variety of production components from multiple sources, one of which is a VW LT cab.



Yes, the body is from the LT and the all the suspension parts are from the T4 but as I want to keep roughly the same track as the LT (the distance from the drop link from the sway bar and the wheel hub is about 15mm different), I will try to use the LT sway bar in the front. I have cut the main support and I have to go get the old LT sway bar on Monday so I can measure up the right distance.


I got a couple quotes to blast the LT body and they were a bit higher than I thought they should be ($1200, and 1500) so I may try to do it myself. 



I am now making the front motor mounts. It is nice to have a working truck to make measurements from. I am driving an orange version of the same truck.


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## CanadaLT28 (Oct 15, 2011)

Well, I have elongated the front sub-chassis by 80mm so that the LT sway bar will fit. Now test fitting the motor and suspension together and looking for any binding spots. Nothing is bolted in quite yet so I can adjust things but I will be putting bag shocks on so there will be a bit more space restriction for the shafts. I may have to move the shocks forward by 20-30mm if possible. The height from the top of frame seems to be about the same from the T4 to the LT in my configuration so that is good.


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## CanadaLT28 (Oct 15, 2011)

More work done. The front Leaf motor is only there to set some spatial requirements for the suspension so it is not in its final position (height). The VW suspension is sitting on it's bump stops so it looks really low too. The torsion bars are not attached yet and when they are the suspension will rise up quite a bit. Most of the frame mounts are welded up but there is a bit more to do.


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## CanadaLT28 (Oct 15, 2011)

Another couple shots of the mounts


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## CanadaLT28 (Oct 15, 2011)

We have rolling stock. No steering but it will roll. One issue is that the rear track is 2040mm and the front is 1860mm. I am getting mixed messages about the handling characteristics of a wider track in the rear than the front. This is not a race car so I don't need to get 1g on the skidpad but I would like it to be stable. I can cut the rear main beam and shorten it slightly (I would prefer not to) and/or I can add a couple spacers to the front to lessen the discrepancy. Not sure what to do.


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## brian_ (Feb 7, 2017)

CanadaLT28 said:


> WOne issue is that the rear track is 2040mm and the front is 1860mm. I am getting mixed messages about the handling characteristics of a wider track in the rear than the front. This is not a race car so I don't need to get 1g on the skidpad but I would like it to be stable.


Although this track combination is less common than having the front track wider than the rear, that's for practical reasons rather than handling; I see no inherent problem.

What matters is that the roll stiffness is balanced between front and rear, but the right balance depends on suspension geometry (including camber change with travel and roll centre height) and load distribution... and track dimensions. If the front and rear suspensions were identical in design it would be easier to compare and tweak them, but in this case they are not even similar (other than being independent and having VW logos cast into some parts ), but that's normal. For stability, just don't go with excessive rear roll stiffness; you don't want the rear to lose more traction than the front as a consequence of tire angle and loading changes while cornering.


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## CanadaLT28 (Oct 15, 2011)

brian_ said:


> Although this track combination is less common than having the front track wider than the rear, that's for practical reasons rather than handling; I see no inherent problem.
> 
> What matters is that the roll stiffness is balanced between front and rear, but the right balance depends on suspension geometry (including camber change with travel and roll centre height) and load distribution... and track dimensions. If the front and rear suspensions were identical in design it would be easier to compare and tweak them, but in this case they are not even similar (other than being independent and having VW logos cast into some parts ), but that's normal. For stability, just don't go with excessive rear roll stiffness; you don't want the rear to lose more traction than the front as a consequence of tire angle and loading changes while cornering.



The stock LT has an equal track as does 2-3 other trucks I have seen but as double wheel trucks "appear" to have a wider track, I will assume the suspension and frame is, as you say, flexible enough take the movement, I won't worry too much about that. My biggest issue is that the battery box will be in there and will have to be quite stiff. I may have to build in some capability for it to move a bit without flexing itself.


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## brian_ (Feb 7, 2017)

CanadaLT28 said:


> The stock LT has an equal track as does 2-3 other trucks I have seen but as double wheel trucks "appear" to have a wider track, I will assume the suspension and frame is, as you say, flexible enough take the movement, I won't worry too much about that.


Many lighter trucks with dual rear wheels do have wider rear track than front (because the single-rear-wheel version has slightly wider front track, but the extra rear wheels tacked on the outside add significantly to track), although medium-duty and heavy-duty trucks actually have narrower rear track, because the effective tire centres are in the middle of those rear pairs.

This should be a suspension question, not a frame question: the ideal frame is infinitely stiff, and lets the suspension work. In reality the frame does take torque and does twist as a result, but that's primarily an issue with uneven ground (which happens regardless of relative track dimensions), rather than the reaction to cornering forces. Even for reaction to cornering force, the suspension roll stiffness is as important as the track dimension - with identical track front and rear there will still be torque on the frame, dependent of roll stiffness and where the body and cargo loads are attached to the frame.



CanadaLT28 said:


> My biggest issue is that the battery box will be in there and will have to be quite stiff. I may have to build in some capability for it to move a bit without flexing itself.


Yes, that's common good practice for mounting on truck frames. Three-point mounting is the straightforward (but not always practical) solution.


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## CanadaLT28 (Oct 15, 2011)

brian_ said:


> This should be a suspension question, not a frame question: the ideal frame is infinitely stiff, and lets the suspension work. In reality the frame does take torque and does twist as a result, but that's primarily an issue with uneven ground (which happens regardless of relative track dimensions), rather than the reaction to cornering forces. Even for reaction to cornering force, the suspension roll stiffness is as important as the track dimension - with identical track front and rear there will still be torque on the frame, dependent of roll stiffness and where the body and cargo loads are attached to the frame.
> 
> 
> Yes, that's common good practice for mounting on truck frames. Three-point mounting is the straightforward (but not always practical) solution.



I need to give the 3 point mount some thought. I was thinking to have the box roll in and out on a couple large bearings then bolted in place. I did lift one corner and was a bit concerned at how much flex the frame has but I also know it has a large 2.4m currently unsupported (from twisting) length which will change when the box is in there.



I think I have the bag geometry set up now. This is at the approximate desired ride height.


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## CanadaLT28 (Oct 15, 2011)

2000kg torsion bars arrived from the UK and are now mounted. The receiver, luckily, is right under the frame member. Tacked up for now. Weld, weld, weld. Once that is under tension, it will be time to set the motor height.


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## CanadaLT28 (Oct 15, 2011)

It's been a while but the rear motor is mounted. Front just needs the rear motor mount finished which will be this weekend.


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## CanadaLT28 (Oct 15, 2011)

Getting closer. Both motors mounted in their assigned spots. See next post


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## CanadaLT28 (Oct 15, 2011)

More pics. I still need to figure out if I can get the Leaf dc-dc and/or charger working without canbus


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## CanadaLT28 (Oct 15, 2011)

One more photo. Sorting out battery box design. I have room for 3 full Volt packs but for now I will just do two. Maybe a 100kwh Tesla pack will come my way some day.


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## CanadaLT28 (Oct 15, 2011)

OK folks, after a lot of consideration, and a desire to have 100kwh of battery in the truck, I have come to the conclusion that the Volt packs won't cut it, mostly for form factor reasons. They are a PITA to make fit in the space allotted and cooling is also complicated. Therefor, I am contemplating using Lifepo4, 100Ah cells to make the pack. I can do it and it is a lot of cells but the price is right and they are tested cells. No cooling needed. 112S3P seems to work. Am I crazy. Standard charge/discharge current is 1/3C


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## brian_ (Feb 7, 2017)

response posted in separate thread: VW LT truck and Leaf motor(s)


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