trans stuck in 3rd gear

michaud2307 · 05-25-2008, 11:43 AM

Ok guys im writing for my buddy truck hes got a 04 duramax with 120000 miles on it and he called me up today with a problem saying that is truck is stuck in 3rd gear,no drive light in the dash,wont go in 4x4 low and hes door wont unlock anymore when put in park,service soon light is on and making clunk from park to drive.any idea

just trying to help a old friend thank for the input!!

**matt_28_01** · 05-25-2008, 04:29 PM

Sounds to me like the neutral saftey switch went bad....it sounds to be a common thing with earlier allisons.....

**BigRedChevy** · 05-25-2008, 10:41 PM

Is he running any kind of tuner? How was he driving when it happened? I would think that he slipped the clutches and put it into limp mode. If he shuts the truck off and leave it off for about 30 minutes it should reset, the light will still be on but it will be out of 3rd gear.

revdevil · 05-26-2008, 09:52 AM

I had the exact same problem a few months ago.
PRNDL switch is the answer. I got mine for a round $30 from Oreilly. Less than an hour to change and adjust.

Did the CHECK ENGINE light come on? Mine set off 2 different codes & this solved them both.

The parts place also had the scanner to use in the parking lot while holding your drivers lic. Used it to reset mine & no problems ever since.

Good luck.