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1971 GMCe Lexus GS450H BMW 530e Tesla Model S powered Electruck

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I will be converting my 1971 GMCe 1/2 ton truck to electric using hybrid and electric car parts here in Sacramento California. This will be a companion thread to the one on 67-72ChevyTrucks.com where I fight rust and do general restoration repairs. I also have a video series on my Good Enuff Garage YouTube channel.

My Experience is limited and summed up by Karen in this Circuit Basics - The Learning Circuit video
I have converted two kid go carts to electric, and a Suzuki Katan aka "Wattana" to electric ten years ago back in the DC motor era. We've also leased a 2013 Nissan Leaf for three years and absolutely loved it, only returned it in hopes of getting the Tesla Model 3 but in 2017 it was not available yet. I'm an IT nerd by day and a JB Welder by night and on weekends, ha ha

My Budget is expandable
I don't really have one but if I did it would be south of $5K not counting the cost of the actual vehicle.

My Goals: An affordable conversion in a reasonable amount of time (6 months or less), on a working man's budget.
Top Speed: honestly don't care, legal highway speed.
Range: eventually 100 miles (based on our 2013 Nissan Leaf 83 mile range experience, we were just fine with that, ended up charging only every other day), I plan on getting there in phases, phase 1 will be a small BMW 530e battery pack

I will be updating and shaping this thread as we go, my focus will be on sharing what I have learned and filling in the gaps that some of the newbs like me may benefit from. I will share where I bought my parts and components and tell you how much I paid for everything.

I know this Forum is a great resource and this is where I have learned about the Lexus GS450H electric transmission or transmotor as I call it, and decided to go for it.

RESOURCES:

BUILDS:

SHOP:

yes Dusty as it is affectionately called is not easy on the eyes at the moment but nothing a coat of paint won't fix eventually
Automotive parking light Tire Wheel Vehicle Car
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The drive shaft joints are unusual for North American vehicles (due to the use of giubos), but it seems to me that a possible bigger issue is making it work with the specific requirements of the coil spring and trailing arm rear suspension, if that's what you have (given that both the coils and leaf springs were available in this generation of the C/K).
 

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Yes my truck has the trailing arm suspension which is what I love about it, and I don't see any issue with running that drive shaft with it, I will just have a drive line shop weld on a universal joint on the end to mate with my 12 bolt rear end and shorten the shaft if need be, am I missing something?
The front giubo works for the transmission, of course, and the rear giubo can be adapted to the axle, but neither of them can handle much angle - they don't need to accommodate suspension movement in the Lexus. The rear giubo's spider could be adapted to a U-joint yoke with a plate, or perhaps the pinion shaft could take a giubo spider, but it might make more sense to just take the spider off the shaft and weld on a U-joint yoke as planned.

The suspension design of the truck works with a joint in the shaft, but that joint needs to be where the arms meet to avoid excessive plunge and rear joint angle change, so it's unlikely that either shaft section is the right length. The plunging section should probably be in the front section (like the slip yoke of the truck's stock shaft), but would presumably work fine in the rear section that moves with the suspension.

It should work, but it's unlikely to be trivial to fit properly. Shortening was mentioned, but is it even long enough? The truck has a longer wheelbase than the GS, and the truck's transmission is presumably set further forward.
 

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with the big stuff gotten we turned to going after the smaller bits, so got this BMW E46 hall effect throttle pedal, now I used to call these things potentiometer but I guess the cool kids call them hall effect, my truck has an ancient mechanical drive by cable throttle pedal so I don't know if, if it was a newer truck with drive by wire if you could use that, maybe someone can chime in and tell us
It's not just what word is "cool"; a potentiometer (or voltage divider) and a Hall-effect sensor are physically entirely different things.
Jalopnik: How Electronic Throttle Control Works

Yes, the same accelerator pedal systems are used in both current ICE vehicles and EVs, but there are different types. Potentiometers and Hall devices are both used in EVs and both used in ICE vehicles, and in addition to the sensor types, the output signal can be analog or digital; Bosch makes all of those variations. Even within the same type of device there are detailed differences which determine which ones are usable by a given motor or engine controller. The current Silverado/Sierra does use an electronic accelerator ("throttle by wire"), but I don't know which type.

Just using what Damien used makes sense to me. :)
 

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I will be converting my 1971 GMCe 1/2 ton truck to electric using hybrid and electric car parts here in Sacramento California. This will be a companion thread to the one on 67-72ChevyTrucks.com where I fight rust and do general restoration repairs.
...
yes Dusty as it is affectionately called is not easy on the eyes at the moment but nothing a coat of paint won't fix eventually
For anyone interested in the thread in the other forum, I can save you some searching:
My Dusty 71 GMC a Mother & Son Project
 

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Why on earth you used a Lexus variant, which the Europeans would because that's plentiful over there, when there was a Chevy TRUCK variant (yes, with the correct output shaft) of the very same transmission, is beyond me.
The GM Two-Mode used in Chev/GMC trucks a decade ago (the 2ML70) would certainly be suitable and a more obvious choice, but it's not exactly the same: Toyota (including for Lexus models) uses an input split design, while the GM Two-Mode has both input and output side power splitters and has all-mechanical modes as well. They won't share any parts. They're "the very same transmission" in the sense that a current GM automatic is "the very same transmission" as a Mercedes G-Tronic, because they're both torque converter planetary automatics. ;) That GM unit was very expensive; I don't know what current availability and pricing might be like.

There is also a current GM longitudinal hybrid transmission of similar design; although GM has never put it in trucks, it might be suitable for a C-10 (which is smaller than current full-sized pickups). It is found only in the Cadillac CT6 PHEV, and designated by GM as the 4EL70 (Regular Production Option code "MRD"). The "70" indicates a GVWR comparable to the earlier 2ML70; that's not as strong as current GM pickup truck transmissions, but likely adequate for the C-10. Again, I have no idea of availability or pricing. Here's an illustration

... from a Green Car Congress article.

I don't know how much aftermarket or hobbyist support there is for use of any of the GM hybrid systems outside of the original vehicles.

In that case I may have found the Global Hybrid Cooperation wiki article and here are some highlights:
Yes, that's the one; the GM designation is 2ML70.

so since I am not interested in a 4WD vehicle and want a 2WD rear wheel drive, my choice in this case is a one year vehicle as opposed to four years to choose from if going with the Lexus 2007-2011 GS450H...
Even if the 2ML70 was only in 4WD vehicles, the transfer case and tailhousing may be interchangeable with GM's conventional automatics, making the 2ML70 convertible to RWD applications... just a possibility.
 

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note the electric Air Conditioning compressor, I am still scratching my head why Lexus would do this and strip the already minimum electron capacity by not using a conventional mechanical compressor, but hewk, what do I know
An engine-driven mechanical compressor would produce cooling only when the engine is running, and these hybrids frequently shut the engine down, when stopped or coasting. I think that most people doing EV conversions would be happy to find that their hardware supports an electrically-driven compressor, because that means that they can have air conditioning in their converted vehicle.
 

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PHASES
COMPONENTS / DETAILS
COMMENTS
Phase 0 - "Minimal Bench Test"Motor
Inverter
VCU (no WiFi card)
Throttle Pedal
60v 5A Bench Power Supply
Car battery

just "bump" the motor

this basically means do the bare minimum to just get the motor (MG2) to spin for a second

only B socket of the VCU wired up, so only 20 of the 40 pins

this is to ensure we have all of the core wiring and connections figured out

Note: we are not even introducing the battery pack to the configuration at this time
I doubt that the inverter will even bump the motor with only a ~12 volt power supply... but maybe.
 

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So Good News Bad News

first the Good News, I got a wiring harness

yes I overpaid, but they wanted $300 originally, I offered $200, they came back with $275, I hit them with $225, and we decided to meet half way (keep in mind this is California so it's the equivalent of $160 in your state, ha ha) shipping was FREE as I just drove 15 miles and picked it up

this is what the crapy low res listing pics looked like

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One of the themes which a user of this forum can choose uses a dark grey background with white text. Setting your text to black makes it almost unreadable. My usual suggestion to users of any forum is to not play with text appearance (size, colour, font) unless there is a specific and significant benefit.
 

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Do you have the Toyota (Lexus) service manual diagrams for this wiring? They usually identify all harnesses. I realize that no one buys service manuals any more, but the content is all available online by subscription, both from the OEMs and from authorized third-party providers such as AllData. The usual professional service is expensive but covers all makes; I bought AllDataDIY access specifically for two of my vehicles for a while.
 

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I searched but could not find anything for free, the best I found I shared with you all in the prior posts. I called my local Lexus dealership today, gave them my VIN and the guy there could not tell which harness goes to the Inverter and he tried and tried, and I am sure the dealership uses the best wiring diagrams they can get their hands on.
I'm not surprised that nothing detailed is free, but in a project which costs many thousands of dollars it might make sense to pay $20 for a month of unlimited access to complete Lexus service information for the selected year of GS 450h to sort things out.

The people who answer the phones at dealerships are rarely as technically competent as a serious DIY auto enthusiast. Dealership service is mostly a matter of reading error codes then unplugging bad stuff and plugging in identical but new replacement stuff. They make money by charging $100+ per "hour" (which usually means 40 minutes of actual shop time) for work, not by doing technical investigations free of charge. Techs are usually expected to bill for more "hours" of work in a day than they are actually in the shop - every minute spent on non-billable activities risks losing their job, so I don't blame them for being less than entirely helpful.
 

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the silliness continues with their numbering system, for instance you wont find A6 or A7 in the list below
...
and what happened to A28 through A40?
My guess is that they were assigned to connectors in the corresponding harness of other vehicles in the same family, with components that are not needed in this specific vehicle. Examples might be the conventional automatic transmission, the neutral and clutch switches on the manual transmission, and AWD system components. It's probably like the permanently empty positions in fuse panels, corresponding to fuses for stuff not in that vehicle. Just a guess...
 

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so here's a mechanical video, where I actually turn a wrench, spin a spanner, and swing a hammer, (no electricity or wire harness talk I promise)

In the video you repeatedly describe MG1 as just a starter motor... this is still wildly incorrect. Yes, it starts the engine, but it is also a fundamental component of the power-split transmission - that's why it's ten times more powerful than a typical starter. MG1 does contribute to output power in some circumstances (when it must motor to force the engine to run at the desired speed and load), and the rest of the time that the engine is running it generates power for MG2, providing a power transmission path parallel to the mechanical power transmission path (and again controlling the engine speed).

Also, if you were to weld gears (never a good idea) to lock MG1 to the output, you would be welding the gears of the power splitting planetary gear set in the front of the unit, not any part of the compound planetary gear set in the two-speed transmission at the rear of the unit.

No, that's not a "clutch plate" or "pressure plate" - there's no clutch - but yes, the part with the starter ring gear is the flywheel. Hey, that's a starter ring gear, so there must be a conventional starter... and indeed there is so that the engine can be started even if the traction battery is low, emphasizing that MG1's primary role is not as a starter. None of the miscellaneous small parts are "clutches", either.

I cringed at the Vice Grips on the splines, as I'm sure many viewers did. ;)

Despite these points which are generally unrelated to use of the hybrid transmission as an EV drive unit, I do appreciate the effort to work through all of the details, and sharing those details with us. (y) I just hope that other viewers will learn from the relevant parts and not get confused or misled by the other bits. :)
 

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The GS450h setup is capable of low or high but as stated no one has implemented smooth shifting on the fly. It is easy to select either gear at a stop or low speed. Might well be handy for towing or hauling, but doubtful it would actually be needed given the available torque inherent in electric motors.
Toyota found shifting between two ratios worthwhile enough to justify the two clutches and control system... in a passenger car. The benefit would be greater in a truck actually carrying a load.

Selecting low range when stopped then being stuck with it at highway speed is a big sacrifice to make because no one has bothered to work out the control signals.
 

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True, but Toyota used this as part of a hybrid system with an ICE providing the primary power. Very different needs and considerations with that set up.
No, not really. The two-speed planetary transmission at the back of the L110 transmission (in the GS 450h and LS 600h) only transmits power from MG2; it has no role in the mechanical transmission of power from the engine via the power splitter, so it is there entirely to help MG2 work better.

For reference, this is the L110 transmission. They also use an L210 in some hybrids now which is very similar but with no high/low at all.
Did you get that from one of my earlier posts? ;)
Yes, the L210 is simpler - in the lower-powered and cheaper models, Toyota skipped the two-speed transmission. In the higher-performance LC 500h and LS 500h, the L310 uses a four-speed transmission. Now, which one of these does an electric-only truck or hot rod most resemble? I would say that it would be appropriate to have choice of gear ratios to get the best performance out of the MG2 which was never intended to propel the vehicle by itself in all circumstances.

And it isn't that no one has bothered. Several (much smarter than me) people have tried/are trying. Shifting isn't a problem. Smooth shifting however...
How is that different from not bothering to solve the problem? It's apparently a lot of effort, but no one has put in enough effort yet.
 

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So.. is your goal to contribute or just be an ass? It's really quite unclear.
To contribute correct information, rather than saying that the two-speed transmission section is only relevant to operation with an engine.

To be fair, you can of course use the L110 "dumbed down" to the same functionality as all of Toyota's transverse hybrids, none of which have multiple output ratios, and that's a perfectly valid choice if it suits the reality of a given conversion project's situation.
 

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a video on battery pack arrangement possibilities...
I haven't watched the video yet, the YouTube description includes
There are six cell modules inside the 530e battery pack, but are they all identical? I answer that question in this video, with the focus on the BMS slave boards.
I noticed that replacement modules are listed in two versions, "positive" and "negative", so I assume that they are mirror images or otherwise complementary configurations to make cabling easier.
 

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and here is my knowledge of metallurgy summed up

there's at least two types of aluminum angle iron, and one has a roundy round corner and the other has a sharp edge, the roundy round is stronger

I bought the roundy round one cause that's what they had in the larger sizes

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They're both extruded. The rounded outside corners don't really matter and the rounded inside corner is structurally desirable if a sharp corner is not needed to fit around other parts. The numbers indicate alloys, not shapes. The extruded shape is not limited by the alloy, but apparently 6061 tends to come in the rounded shape for structural use while the 6063 tends to come in the squared shape for appearance in architectural use. You got lucky by getting the structural extrusion for your purpose.

Aluminum 6061 vs. Aluminum 6063
 
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