My truck wont shift out of 1st? What the hell

[pOrk]

Truck is stuck in 1st, seems like if I try to shift manually it feels the same as 1st in all 3 gears and in D it hums away at 4500 rpm at 50 mph. Took me half a tank to get home from Sussex.

I'm wondering if it has something to do with my recent un-installation of the Interceptor gauge, but I have no clue. No lights either. Any ideas?

[BAD LS1]

did u shut it off and restart it? If so make any diff? Sounds like a stuck 1-2 solenoid or something.

[SmokinRAM114]

does the PRND21 gauge still back lit? my duramax did that when the pinto sp? switch went bad.

[wrath]

Your truck should have a cable that goes into the transmission still. So, as long as the cable moves then the truck should know what needs to happen. There is a sensor that lets the computer know what gear YOU want but in reality it's the computer that does all the shift points with the exception of second gear. If you put it in second gear it won't downshift to first or upshift into third/drive.

If anything, it should be stuck in 2nd gear as that's the default limp mode and it almost always works unless it's a catastrophic failure.

What size are your tires and what gear ratio? 50mph at 4500rpm seems a little low in first gear unless you have 33" rubber with 3.42 cogs.

[pOrk]

33" Tires with 3.73's

Its been turned off and restarted a few times, no change. How much of a ***** is it to replace the solenoid?

[wrath]

Oh yeah, I forgot, you have a 4L80e. Crappy first gear.

I'd take it to someone here that has a Tech2 so you can see what the line pressures are and see what the TCM has logged.

You have to pull the pan and it's not that bad if you have a clean garage to work in. I think A solenoid and B solenoid are still around $35 each.

[pOrk]

^ Fair enough, I will grab a shop manual and see what I can dig up. I'm going up to Hall tomorrow to use their tech 2. Thanks for the advice!

[wrath]

Wow, can tell it's been a while since I've had a 4L80e apart. They're only like $15/each on GM Parts Direct.

So, in theory, you can get a filter kit, A and B solenoid, and 5 quarts of your favorite Dexron III replacement or Dexron VI for under $100 and have yourself a red and slimy day.