Another LB7 YAK 6 Speed Conversion
Had a 2004 GMC Sierra brought up to me from Alabama a couple weeks ago the truck was having electrical issues and not wanting to go into gear P0872. The customer was having issues with his Allison 1000PK transmission prior so he purchased a 6 speed conversion from us. After installing I tried to walk him through some diagnostic test & other fixes that needed to be addressed, but its hard for most customers to self diagnose especially over the phone / live chat that's why there are guys like us who do this for a living. He received the truck from his father and wanted to get the truck back up and running rather than sell so I offered to have him get the truck transported up and I would diagnose and fix the problems. After some initial diagnostics and test I determined his engine / transmission harness was wore out and in need of replacement amongst other body harness fixes conducted along my inspection. Along my inspection I also found other interior systems & wiring were repaired improperly and I did what was needed to get the truck 100% operational. I'm happy to report the truck is now running and shifting perfectly. This truck has one of my 2011-2019 Allison 1K/2K valve bodies with upgraded internals and custom harness. I started moving away from the generation 5 valve bodies due to my belief the 01-05 trucks pumps having issues keeping up with fluid demand due to the fully redesigned valve bodies. What happens is the valve bodies will shift perfectly under light load then as you get into higher load/TQ situations the pumps just cant keep up and holding pressure starts to fall off this is really noticeable in tuned trucks vs stock tuned trucks. My fix has been for most to install a older Allison 1k/2k system in the truck and this fixes most if not all shift performance issues in the 01-05 trucks. Now with this truck he does have a Jasper reman Allison 1k in there and my thinking now is if the newer valve bodies can work but you have to have the proper calibration as well as a extremely healthy Allison to go this route. I have done a lot of both systems and it really just depends on the truck and transmission health. I was happy to let him know he didn't need to replace the Allison and I was able to fix what was needed for proper operation all around. I also installed some extra stuff I had on hand on the house cause that's what I do help all my customers get the most for their money.
Below I attach some logs and photos of the truck its ruff around the edges but mechanically truck is very sound.
Reply With Quote