dtt trans sporatic overdrive

[carson6]

My trans is a month old... won't shift into overdrive... what can it be..... my installer did a poor job with the shift linkage... . he may have screwed something else up. On my 04

 

[TCDiesel]

OD solenoid or stuck OD Valve.

 

[cerberusiam]

. . or transdcuer\gov solenoid, OD clutch pack lip seal, could be any number of things. Add the mystery switch to pin #6 of the trans control harness and see if you can get it to operate manually.

Are you getting TC lockup in drive and 2nd gear?

 

[carson6]

s in first second 3 rd ... . I did notice it stays in first longer before going into second... . which is cool... ... after freeway speed for twenty miles it shifts into od... . could it be a linkage ajustment... had a good mechinic... but now a disgruntaled employee... thank you guys for the info

 

[cerberusiam]

Nope, linkage won't cause that. If it is going into gear after running a while I would replace the transdcuer and get a GM gov solenoid.

 

[carson6]

I tried redline down hill ... shut off ignition . . turned it on . . disconected batteries... Pac brake on ... then off. romped on throttle... . manualy shifted thru the gears... nothing worked... . jumped in the truck at lunch and has over drive... . maybe a loose wire??no codes... . anything simple or obvious I could check?

 

[cerberusiam]

Codes?

Check the trans control wiring harness, make sure the plug is seated solid and dry inside.

Manual switch to check operation and the gov solenoid\transducer if you cannot find wiring issues.

 

[sag2]

Temp sensor bad and it thinks the trans is too cold?

 

[p-Bar]

Maybe the controller for the Pac brake is hosing something can you disconnect that?

 

[carson6]

No codes... I don't know how the Pac. Brake was installed