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Some huge news: I've done a bunch of reverse engineering on the Vtrux's CANBusses and now we have a bunch of CANbus specs for helping diagnose these trucks! Quick summary: the Vtrux has 3 CANbuses, I've been calling them them the Powertrain, OBD, and Vehicle buses. Most of the Via high voltage components live on the Powertrain bus: battery, DCDC, generator inverter, charger, power electronics water pump, high voltage AC compressor. The drivetrain inverter and the original GM ECM live on the OBD bus, and the EBCM (brake/traction controls, etc) live on the Vehicle bus. Via's controller spoofs certain messages between the GM ECM and the EBCM to keep both happy (EBCM gets fake always-on engine data, for example). All 3 of the buses are broken out at the white DLC connector below the dash - the Vehicle bus at the standard OBD canbus pins (CAN-H 6/CAN-L 14), then Powertrain at CAN-H pin 1/CAN-L pin 9, and OBD at CAN-H pin 10/CAN-L pin 2. Both of my trucks came with a breakout harness breaking these out to secondary connectors with each bus on the primary 6/14 pins, such that a standard OBDII connector to CAN adapter can interface with the buses that way, and I bet most other Vtruxes out there have these. P2 is the powertrain bus on mine and P1 is the OBD bus. On one of my trucks, this harness was used to break out the OBD and Powertrain buses to wireless Bluetooth dongles, which were then connected to an iPhone tucked under the dash with a logging app. I was able to jailbreak the iPhone and pull the logger app off of it, then with the help of LLM tools using Ghidra, decompile the app and extract the CANbus specs from it. I have not been able to figure out any way to read diagnostic codes from the Via controller - everything I've been able to figure is just directly analyzing log data directly. Which aligns with how Via used to support these trucks, with the mail in logger. But now we actually have meaningful fault diagnostic data - for example, the other day, I was trying to reinstall a pack in one of my trucks after replacing the contactors and cleaning up some corrosion, but the truck wouldn't turn back on when reconnected. I was able to pull a log and diagnose the issue as a high voltage interlock fault, and sure enough, when I got back home and opened the pack back up, turns out I had forgotten to reconnect the interlock connector on the charger HV DC connector which I had done some corrosion cleanup on. Here are some links to the repo where I documented all the findings, including CANBus DBC definition files: https://github.com/nickyivyca/canbus-reveng-vtrux-coda https://github.com/nickyivyca/canbus-reveng-vtrux-coda/tree/main/projects/vtrux If you are trying to diagnose issues with the trucks, probably the best option is to take a CAN log while the issue is happening of the Powertrain bus. Then either you can use the tools in the repo yourself to check the log, or you can send the log to me and I can try taking a look. If you do not already have a means of taking a CAN log then these will work if you have access to a Linux based computer that can use socketcan: USB to CAN/DB9 adapter: https://www.amazon.com/gp/product/B09K3LL93Q DB9 CAN to OBD adapter https://www.amazon.com/gp/product/B081N7G2BR Important note: my previous assumption about my coolant pump was wrong. The truck does NOT suddenly turn off when either drivetrain or generator motor overheat. I did separate tests for both motors, unplugging the coolant pump and then driving around until the motors overheated. Both motors gently reduced their torque output when they overheated. It is still unclear to me exactly what was causing my truck to randomly shut off, since I only have one log of when it randomly shut off on me, which does not indicate an interlock or isolation fault, but swapping the battery pack with another running truck completely fixed the issue, so the issue was somewhere in the battery pack. I ended up replacing all 5 contactors, which looked like they had gotten hot over time, so once I can get it back in my other truck I can see if that indeed fixed the issue.

i thought it would be snake oil, but i have to admit valvoline restore and protect does work. my 2.7 would use 1.5 quarts in 4500 miles and i would change the oil. my last 2 oil changes i used valvoline and it has reduced my consumption by half a quart already

Not only do these newer engines have low tension rings, they have narrow rings for reduced friction. The oil control rings have the narrow expanders between the rings. These don`t flow like the ring packs from the old days, even when new. So, one can see what happens when a GDI engine piles on miles with mostly clogged expander holes. Well,let`s not leave out the port injection and carb guys. Them too. One needs to keep these things clean from new. That`s why I will only buy a new modern engine.

Interesting question as this is an unusual product. It cleans, yes but it also has a decent HTHS viscosity. 3.3 cP last time I looked. Nearly meets the spec of an SAE 40 (3.5 min). Seems to have a decent add pack as well. So, especially in the case of quart million mile motor....keep using it. If the rings needed freeing at say 60-80 K then I'd use it until it stopped improving and see where I was. If the recovery was partial (uses a quart between 5K changes) then I'd stay with it. Some bore/ring damage has been done and a cleaner oil won't make it last any longer. If however it fully recovered (zero to less than a cup, by dipstick eyeball) over that same period of time AND I was inclined to run it until the cows come home then yea, AMSOIL SS or Red Line HP or one of the offerings from High Performance Lubricants like No-VII 5W30 would be on the short list. If I were just going to trade it then stay with the R&P. It will do just fine. Even for the next guy. You are also in a unique position as a Master Tech and better able to gauge the here and now condition as well as the likely future that I could from a distance. Trust your training. You're good at this. I'd add this as well. ANY oil is like a sponge. It will only hold what it will hold so even this super cleaner has a limit as to the miles that can be run on it and that varies with blowby and season.

I'm not Grumpy Bear, but yes. Stuck rings were and are still a problem before Valvoline Restore and Protect hit the market. R&P was released to try and resolve engines plagued by that problem. Newer stuff runs hotter at the top of the piston. That combined with fuel quality and fuel burn quality during combustion has contributed to higher odds of carbon build up at the top of the piston and the ring grooves. I can tell you first hand, R&P WORKS. I bought a 2009 Pontiac Vibe last year with the notorious oil consumer 2.4 2AZ-FE Toyota engine under the hood. Toyota had built these engines prior to 2011 with new (at the time) low tension rings but also had a questionable oil drain back passages in the pistons that would clog easily. I got the car with 234,XXXmi on it. It, no joke, used 1 QUART of oil in 400 MILES. I'm on oil change #4 of R&P. During the last fill, the consumption DROPPED to 1 quart in 2000 miles. I haven't put enough on the 4th fill to see if its improved further, but I suspect it will. I tried one other method prior to R&P, which was BG EPR (Engine Performance Restoration). That didn't touch the consumption one bit. So yea, its actually more important than ever to use a high quality oil from day one on a new engine, or if there is oil consumption present on an existing engine, using a product like R&P or the new Mobil 1 Advance Clean to try and resolve consumption issues and clean up the piston rings, ring grooves and oil passages. Question for you. If you were running R&P, would you just stick with it? Or run it long enough to see enough consumption reduction (lets say a quart in 3000mi or less than that) and then switch to something like Amsoil or another higher end product?

You went 5000mi on 2 quarts low? Possibly repeatedly it seems? And then are mad at GM for your neglect of maintaining proper oil level? GM max allowable consumption is 1 quart in 2000mi. You are below that threshold and would be considered normal. Oil level should be checked at every fuel fill up. There are also products out there that you could have tried to reduce oil consumption like Valvoline Restore and Protect which would have likely eliminated or close to eliminated your consumption issue.

Why not go OEM Original Rear view Camera