Guy comes in and says he has a 700-R4 that shifts into 1st and 2nd just fine but won't hit 3rd or 4th. It's a 91 Vette engine and trans transplanted into a truck. We talked about the wire to the lock up that hasn't been hooked up yet. Asked him if he was sure it was only the first two gears and he's positive. The question is, does the 4L60-E have a TV cable? I'd guess it doesn't. The puzzling part is, it all worked fine before he pulled it from the 'Vette. Will an improperly adjusted TV cable not let it shift into 3rd and 4th? I thought it just controlled the speed that it shifts at. Educate me guys (& gals).
Confirmed that issue. Still need to figure out if it's a simple cable adjustment on the 700. Thanks Jim.
If that's a 700R4 it will have a TV cable, if it shifts 1-2 at a reasonable rpm it probably isn't TV pressure causing the problem. If the cable is too far out of wack it'll shift at very high rpm...very hard because the line pressure will be sky high. If it worked prior to pulling it out of the 'vette maybe the linkage is messed up or it mysteriously blew up 3rd gear.
Does the transmission attempt to shift and just slips or does it just not shift and the rpms continue to climb? I don't think is a cable problem cause you say that it shifts into second alright. The cable does what a modulator would do on a 350 or 400. The cable adusts shifts timing and shift feel. What kind of truck is it in?
If it is an electroinc transmission then it sounds like the shift solenoids. There are two, They are copper wire wound thingies on the back part of the throttle body. Not sure which one handles shifting into 3rd but since your in there might as well replace both. Think they are about 20 bucks a peice. There is a U shaped pin that pulls out the holds each one in place then it just pops out, pop the new one in and replace the pin and plug the wires back in. If its not electronic then have no idea. I had the same problem in my 2000 GMC truck and this was the problem.
squirrel is right, it wouldn't be electronic. You could go the standard diagnostic route if you had a pressure gauge to screw into the pressure taps. The thing could have a stuck servo (the device that engages the 2-4 band) or any number of internal parts stuck-broken or whatever. Push the TV cable back into the housing all the way and see if you have early really mushy shifts all the way up throough the gears, then if you can't adjust it the prescribed method (cable fully extended at wide open throttle) pull it out half way and try it. Chances are it won't be the cable......time to "open her up for a look-see inside"
This won't help you Stevie, but somebody reading up on 700s might encounter this...... Owned an 84 Corvette once that suddenly wouldn't shift out of low Turned out the plastic speedo gear in the tailshaft was broke
That is the governor gear and yep......if it gets trashed and you have no governor pressure you will have severe shift problems too!! They usually strip out (or "apple core") when they fail since the gear is plastic. But I believe you said it has an OK 1-2 shift so that would sorta rule out a governor problem.
I have a 700r4 in my car and bought a lock up kit from summit ( I think ) for it. If it is electronic you need to replace the selinoids because you have no ***putor in the truck to run the ******. The ****** is not fully locking with out this kit. It my seam like it is but be ware it's not. Hope this helps.
I'l make sure it is actually hitting second next time he comes around. It's a local s****per that finds me some pretty good deals on vintage tin so I try to help him out when I can.
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