tranny want shift into 6th gear

[bchaney]

my buddy just bought a 07 duramaxs and it want shift into 6 gear! he said that it shifts fine in every gear until u get to 6 gear ! i told him to see if it would do it manually and it would not and i had him pull the codes and this is what he got p0700 p2723 p0776 p0735 can anyone help us and with what is wrong please! he bought the truck from a oil field company for 5k cash it only has 150k miles on the motor runs great this is the only problem it has !

 

[LBZ_Duramax]

I would clear codes and try again.

 

[bchaney]

we did then they pop right back up ! i honestly think we are just gonna have to pull it and have it rebuilt

 

[THEFERMANATOR]

we did then they pop right back up ! i honestly think we are just gonna have to pull it and have it rebuilt

I know the P0776 is a BAD code to have, and the P0735 I believe is excessive slippage in 5th gear. You put all of these codes together and it doesn't look good. Has this truck been tuned before? It doesn't take much of a tuner to limp an ALLISON.

 

[Mike L.]

Transfer case?

 

[bchaney]

havent thought of that one !!!:hug: