Thundernuts

New to the forum, but not to cars. My sister drives a 1994 silverado with a 5.78 liter and a 4l60e trans. Today while she was driving it, she said it made a kinda "clunk" noise and it felt like it was slowing down(I gathered later this was the feel of the car slipping out of gear) and then the truck would no longer drive. She was doing 45 mph at a steady cruise when it happened. The truck has given no signs of trans issues before, it has 184k miles on it and the fluid looks nice and red..as maintenance has always been kept up on it. I pushed the truck home using my car, and when we got it in the drive way, I verified that the truck has no forward gears, (whether in drive or manually through the d D 2 1) but DOES have reverse, and it works perfect, but only reverse.

I am not afraid to rebuild a trans as I have done about 3 in the past..but I can't find anywhere on the net where this problem has occured. I can find all day where reverse is out or they have some forward gears..but not where they have reverse and NO forward gears. Can anyone out there tell me what I should expect when I tear into the Trans? basic rebuild kit doesn't sound like it will be enough to fix it..I am thinking I broke a shaft or something...any help is much appreciated. thanks in advance

livinginsuburbania

were you able to figure out what the problem(s) were? I've got a 97 Suburban with no forward gears but reverse is good. If I put it into 4x4 mode I don't have forward either. that says to me there must be some linkage that has come undone. I'm interested in hearing what you did to fix the problem.

livinginsuburbania

did you figure it out as to why the forward gears didn't work?

epidemic

I also lost all fwd gears but rev works perfect like off factory floor. HEY THUNDERNUTS what did you find out? Can email me to if cool with that. send email to epidemicevent@gmail.com or PLEASE re post to let us know what you found out.

In dire straights here

Thanks! T

johntaps

I think its time to change the transmission system but before that look out the gear shifter cable and lever. Loose cable or lever can make the problem as you have mentioned.

Allan In NE

Make sure the shift cable isn't broke. If it is okay, yank 'er out of there as the forward clutch has failed, probably due to a torn seal.

Oh, and 187K is a heck of a lot of miles on one transmission.

Allan

RacerX

No shift cable after 1993. All electronic.

Allan In NE

Sir,

Don't confuse the man. Of course it has a shift cable and very well may be the source of the problem.

Allan

RacerX

4L60-E has an electronic valve body so it doesnt need a shift cable or kickdown detent cable. All there is is a mechanical gear selector(the PRNDL) and harness connectors for the valve body and speedometer. 700R4s have shift cables, but anything built after model year 1993 is electronic.

cleveland63b

close but wrong theres still a shift cable way up into the vortec days, if you need proof i can look it up but im feeling lazy

I've pulled plenty of pans on 4l60 and 4l80es and that shift cable is right in the friggin way