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3rd gear!

1314 Views 5 Replies 5 Participants Last post by  96wayne
I got a 96 DCM SS Impala

So here's the issue, once i drive for 5-10 min, the tranny seems to get stuck in what would seem to be 3rd gear. Wont shift down unless i do it manually. From the threads i looked up on this forum seems to me i either have a bad solinoid or a bad harness, which is causing "limp mode".

Does this all seem to be accurate?
Is there an easy way to tell if the problem is the harness or solinoid?
If it is the solinoid, should i just rebuild the entire trans?

ps- im not overly amped about jumping to a T56 but if someone has a great deal on an entire install kit i'd def be interested.

Thanks in advance because i know this forum is awesome with responses to this kind of stuff.
1 - 6 of 6 Posts
It's unlikely to be the harness. The solenoids are easily changed during a simple trans service and are not expensive at all. I have seen this situation however one time that the problem was actually in the PCM.
The first step is to see if the transmission has set any trouble codes..

It sounds like the transmission is losing power to be honest with you... A solenoid is certianly easy to change and would be the easiest most likely culprit here.

If the transmission is not losing power, and the EMI fuse under the hood is good i would replace the solenoids as mentioned above first then go from there.

Other possibility is a hydraulic crossleak applying third gear when the fluid thins out and gets hot.

dealership recommended that I get the transmission hooked up to the computer and get it reprogrammed, or get the most recent update done. Which will be free since my best friend is the service advisor. The mechanic we asked about the problem said the solenoid is probably just getting stuck either because its worn out or theres some bad fluid in there.

So I'll get the update done, and if it happens again i'll go ahead and replace the solenoids with a tranny service.
You get two props:
1. for actually getting it scanned.
2. for spelling "solenoid" correctly.
3rd gear

let me know you come up with because I'm having the same problem and I had the tranny serves. The EMI fuse is good next move is tranny harnesscwm3
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