| Allison Shifting Issues
2001 GMC 2500HD
5 speed Allison
~183000 kms
No mods of any kind...yet.
During a full throttle accelerations away from a light, my truck shifts into 2nd (or 3rd) and redlines, but won't shift up to the next gear. I am stuck at 60km/h. If I blip the throttle, it will make the shift and take off.
Same thing happens if I try and pass, it will shift into 3rd (or 4th) and redline at 80km/h and just sit there w/o shifting.
I had the truck scanned but don't have the codes with me, something about communication issues between the computers?? Fuel filter has about 80k on it.
Any thoughts or do I need to get the codes? (wrote them down but left it at work) |