I swapped an L96 6.0 with 6L90 into a '87 squarebody. I have limited tuning knowledge but like learning and enjoy the building as much as driving them. I've done some TPI tuning on late 80's stuff using Tuner Pro / Moates and so far I'm really impressed with HP Tuners. I modified the OE harness myself and everything seems to be working except I cant get VSS/OSS signal. The Motor/Trans/ECM/Accl Pedal all came from the same donor truck. The caveat is the trans was a 4WD which would have used the VSS on the transfer case. I swapped the trans output shaft and tail housing to make it 2WD and I thought it would be as simple as using HP tuners and swap VSS/OSS Location from "After Gearbox" to "No sensor" and it would then use the OSS internal to the trans. I can communicate with the trans fine, read the gear position, etc, just no VSS. Do I need the OS from a 2WD truck? Would it be the ECM OS, Trans OS, or both? Would I have to buy credits again to swap OS? Could I segment swap? I attached the tune and a log. Sometimes it shows 0MPH and sometimes it shows 158 MPH...Just depends on its mood. I did put a cam in (and deleted VVT) and that's why im trying to tune VVE by zones to try and make it simple. In the Log I've failed the MAF and running in open Loop. Its really rich in Park but for some reason if I put it in gear it will pull within 2% of stoich. I have a long way to go on the tune and my learning but I think I need to figure out the VSS issue before I waste any more time trying to dial in VVE. I really appreciate any help I can get...I've searched and searched before posting this so I don't waste anyone's time. Thanks again.
Also I have not driven the truck yet...Just have it in the garage and have put it in gear on the stands to confirm no speed being reported.
Think I got it figured out and wanted to close the loop Incase anybody sees this in the future. The VSS/OSS sensor location should be set to after gearbox and I had to do a write entire on TCM for it to work. I had tried changing different settings here in the past but only did write calibration and it didn?t change. Easy fix after all
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