I have an 01 tahoe 4x4 and if you put the trans into dr wont move no noises pull into 3rd it will go and once its rolling you can put back into dr and it works fine stomp on it it downshifts like it is should until you come to a complete stop then back to 3rd and off it goes and on long drives on the hwy no probs at all its got me scratching my head. Any help is appreciated.

 

Any codes?

 

Normally I would say you have an issue with the input sprag. With this type of failure you will not have movement in the OD or 3rd gear shifter position from a stop. Being that you have movement in the D3 position I have to ask if you have a sonnax hd 2-3 shift valve installed in your trans? This modification will allow the over run clutch to be applied in the D3 position and will give you movement in the lower ranges if an input sprag has failed. Has this trans ever been worked on and have you had the pan off the trans to take a look for debris?

 

still stocker never been out no mods at all have not hooked the modis to it yet guess that would be a good start before asking dumb questions with out any good info to go with it lol.

 

any chance you been off roading lately? kinda seems like the shift linkage at the trans has been damaged... meaning when you have it in OD it might actually be hanging in neutral, then when you pull it into 3rd the linkage hangs somewhere between 3rd and OD which just happens to work like OD. IDK sounds like a possibility.