Hello,
This is my first Diesel and my first Chevy Truck.
My transmission only has First and Second Gear Only (no reverse, third or OD). I bought it this way, please don't ask why - I get enough grief from my wife.
I've done a lot of searching on the web and have found conflicting info on the root cause and what the fix would be.
I don't now very much about transmissions but my gut tells me that it is more likely an electronic or hydraulic problem rather than a catostrophic mechanical failure. But maybe this is just wishful thinking and am in denial about the possibility of replacing a sun gear, sun ring, sun shell, sprag or some other part requiring a rebuild (or close to it).
I bought the ATSG (Automatic Transmission Service Group) manual "THM 4L80-E" for this transmission ($25 download PDF).
In the troubleshooting charts they call out this specific condition "FIRST AND SECOND GEAR ONLY"
INSPECT COMPONENT FOR CAUSE
Solenoid B (311)Stuck Off
Loose Connector
No Voltage to solenoid
Solenoid o-ring failure
no PCM signal to solenoid
2-3 Shift Valve Stuck
Quad Driver Module Failed
Possible Codes:
68 Overdrive Ratio
81 QDM & Solenoid B Fault
85 Undefined Ratio
87 Solenoid B Stuck Off
I was getting a code 87 and quickly (maybe hastily) went and replaced the 2-3 Shift Solenoid. This did not fix it.
While I was in there I should have checked the voltages to check for loose connecter, no voltage to solenoid and/or no PCM signal to solenoid.
I also should have checked the 2-3 Shift Valve
Does anybody know if I should see voltages if the truck is not running, but the ignition is in the "on" position and I put it in reverse or 3rd?
Any experiences that you can share would be appreciated. I'll post back with my results.
Thanks!
Paul
P.S. I bought a B&M Automatic Transimssion Drain Plug Kit #80250 to make future transmission fluid changes less of a hassle - in my opinion balancing a tray of hot tranny oil over your chest or face should be avoided
P.S.S. I may have posted this in the wrong forum.... should it go in the "2500HD/3500 HD Trucks & Drivetrain" forum?