cwdillon

Hello, I have an 88' Chevy 1500 Silverado shortbed 2WD I bought a few months ago and drove and ran just fine. A few weeks ago, out of nowhere, no symtoms or problems, the truck quit shifting into 3rd or OD, just have 1st and 2nd(it is a 700r4 w/350 engine). I had the fluid and filter changed and still the same problem, the fluid was still decent and they found no metal what so ever in the pan(I was present and watched them do it cause I was very curious). What I am wondering is do I need a new transmission or do I need to change something else like the modulator or solonoid? Also, the check engine light use to come on and off frequently, but when this problem started, it hasn't come on since.

Dazed and confused for so long...

Chance

Bolander

[hr]Does your truck have cruise control? If so, I could be a simple as a bad BRAKE SWICH! If the brake swich goes bad it will send a false signal to the torque converter causing the crusie to randomly turn on and off thus causing shifting problems.

cwdillon

Thank you Bolander for responding....Now that you mention it, I had some trouble with the brake lights not working all the time when I first got it, it ended up being a wire came out of the junction block of the harness right above it, I'll have to check the wiring again. Also, the cruise control has never worked since I've had it, but I look it of to see if anything is not right in that area.

Bolander

[hr]That was my problem on my truck. Took me forever to find it! I chased the problem for a week!

Good Luck - Hope thats it!

An89Chevy

my 89 still has the problem, it dosent have cruise control. the 700r4s just cant handle the torque of a 350 and the "something-valve" blew cant remember its name.. i need to get my transmission fixed.. and the sucky part was is it was new a month before it blew....does your truck shift hard... improperly adjusted tv cable might be the problem and led to transmission death.