2001 chevy 2500hd 8.1l gas engine allison trans wont shift after 2nd what shud i check

SOURCE: chevy transmission hangs in 2nd,

It just holds 2nd forever. Is the 1-2 shift point high?

SOURCE: 2001 Chevy 2500HD Whining

these transmissions have three sets of planatery gears the whining you hear is simply the gears doing thier job. You have to remember the allison trans is basically the scaled down version of the heavy duty isuzu truck trans they are designed more for thier load capacity then for comfort

Harvey N Tawatao

• 3854 Answers
• Posted on Jun 26, 2009

SOURCE: Can anyone please tell me the location of the

The A/C service port is on the accumulator (Filter/Seperator i think is what you called it)on your Silverado. Good luck and keep me posted. Be glad to help.

Richard Lukszys

• 55 Answers
• Posted on Nov 07, 2009

SOURCE: 2004 chevy silverado 2500hd duramax with allison

could be the alternator

SOURCE: need a repair manual for a chevy 2002 2500hd 4wd with gas engine

Depending on how technical you want to get try e-bay or a local book store. They would have a good choice and alot of different types you can purchase.