RavageTheRoad

Self explanatory. My tranny won't shift right after over a year of being absolutely perfect. It acts as though the TV cable isn't adjusted properly, even though it is. I had a lot of experience with TV cable problems when I first got the car so I got fairly well educated on it, it doesn't seem to be the problem here. Sometimes it will shift as high as 3k rpm at 30 mph into 2nd. And 3k at 55 or so into third, etc. Then when I hit operating temp its fine, maybe with a slight slip going into 3rd if I'm on a hill and barely accelerating. Two things I can think of:

1) Tcc? Mine never worked. I tried using a toggle switch for manual operation to no avail. Still have the switch in the circuit, could that be messing with it even though the tranny is mechanical?

2) fluid leak? I know my pan leaks a little. I have to top it off about every oil change, sometimes up to a full quart. Would that be a possible cause?

If the tranny is on its way out, is it cheaper to swap a junkyard one in or rebuild the existing one?

RavageTheRoad

Bump... Its getting worse and im completely stumped.

vortec350s10

Umm, have you checked the fluid level? If the level is good, what does the fluid look like and smell like?
Rebuilding a 700r4 is not too difficult, you just can't be one of those guys that tears it all apart and throws everything in a big pile to sort out later.

RavageTheRoad

The level is fine. it doesn't smell burnt. I'm sure I've added enough to equal almost a full flush since I've owned it so the fluid itself should be fine. Haven't checked for fine particulates yet. Just looking for things besides the tv cable that would cause it to act that way. It's at the point now where it picks and choses when it wants to shift properly now, which is becoming a rare occurence.

bigal55

iTrader: (1)

How about the governor? Sticking, broken spring, loose or stripped gear? Pop the cover, pull it out and see what it looks like.

RavageTheRoad

New issues I've noticed since my last post.

When idling in gear, the car has a slight rhythmic "shake" like a misfire, which isn't present when in neutral/park. I can feel the shift lever "clank" when the car shakes and hear what I first thought was my heat shield rattling but now I'm thinking maybe it's something in the drivetrain.

If I drive in regular D, it will lock up every gear. It holds 2nd and 3rd even while braking until it downshifts and locks/holds the lower gear as well. driving in OD still shifts high but it wont lock the gear.

StealthESW

Once they start to go, they just get worse till they quit.

It could be a number of different things. You need to have it checked out. The 700R4/4L60 has a lot of parts that could cause problems i.e. slipping clutches, stuck valves, broken springs, or just worn out bushings and seals etc... Your torque converter could have an issue and that could cause the shudder you are feeling.

The best way to get a diagnoses would be to let a transmission service guy have some time with it.

If the one in the car can be rebuilt, I would do that. There are differences in the valvebodies and governors for each model of car. Also, there are a few case differences i.e. K case for 4x4, V case for Corvette, V6, or V8. The pump had different improvments through the life of the 700R4/4L60, also. You are in good shape if you still have the original '91 trans.

If you rebuild it yourself, it can be done, be sure to get a repair manual and a video if you can. There are a bunch of parts and it is possible to put some of those parts in wrong and not know till you take your first test drive. Go slow and take lots of before pictures during disassembly, just in case.

Good luck.

RavageTheRoad

looks like I fell victim to occam's razor. Tv cable ratcheted out when I adjusted it, 0ut I checked the tightness as a last resort and lo and behold, the cable was just stretched out a little bit. Put a zip tie on for now and it shifts better than ever... I appreciate all the help and responses.

Bob88GTA

iTrader: (2)

Just my 2 cents, but if you "added enough to equal almost a full flush since you owned it so the fluid itself should be fine", you probably, and it wouldn't hurt, to change the tranny filter and a pan gasket.

Again, my 2 cents.

topless87

+2 on filter check and replacement. It could be clogged up giving you some issues also.

RavageTheRoad

I'm just gonna bite the bullet and dive in. the cable adjustment worked for a day, but it stol gets moody on me and shifts high/max pressure from time to time. Will be fine, then start acting up for no apparent reason until I park it for a few hours.

topless87

Atta boy!! I have a post up but no answers on it. My sons 700r4 will drive fine in OD but acts like its in neutral if I try to manually shift it. Ever had that problem? Though I'd ask but not hijacking your thread. Thx

RavageTheRoad

That... Sounds really strange. Maybe take a look at the linkage? Afaik the same clutches are used regardless of gear selection. Ill post what I find s far as my situation in a couple days when I drop the pan and take a look.

RavageTheRoad

Still haven't had a chance to drop the pan yet and look inside, so I'm just wondering what components to look for that would cause this issue when I do. It has completely stopped shifting normally no matter what I do with the tv cable. I've tried adding zip ties in hopes the cable was stretched. It would work temporarily at first, I would push in and reset the adjustment and it would work for a day. Now nothing. Full line pressure shifts at high rpm every time. I can pull on the end of the cable and it will pull out about 3 inches but it has some tension and a complete stop at the end of travel. So I guess it's still connected. It is tight at wot when adjusted. All shifts are still firm. I know the cost of a gasket and fluid to inspect it are small but I don't have the cash to open it up on a maybe. It's there a good chance something is just out of whack or is the transmission most likely just done? It has 140k on it and I know the idiot po did not take care of the car.

vortec350s10

I have only skimmed over this whole thread to refresh myself and I could have missed something, but the governor could be the culprit here. So it shifts firm all the time, and sometimes shifts only at high rpm? When you messed with the tv cable the one day and it helped, did it shift at normal shift points?

RavageTheRoad

It used to shift OK after a cable adjustment, now it doesn't matter what I do, it never shifts properly. It's there any ecm parameters that control it? My temp gauge keeps getting very high even with the fan on but I never get any boiling so I'm thinking my cts or temp sender is going out and I know that is an important sensor s far as closed/Oren loop operation. Anyway, so the governor could be a likely culprit? Cracking the pan open would set me back for other things, so I really would like to avoid that if necessary. I may end up having to sell it.

vortec350s10

I would remove the pan first, and see what you find there. Then as long as you are under there, if you are willing, drop the crossmember and bring the trans down far enough you can get at the governor cover. If it's never been off, it can be a real pain. Getting it back on straight is even tougher, the floor is in the way enough that you can't get pressure on the top half of the cover to fully reinstall it. If this sounds daunting to you, I would just do the pan and filter and if you don't find anything there, have a trans guy inspect the governor for you. The ECM does nothing with the tranny besides supply power for the torque convertor lock up.