Half-FastRacing

Gentlemen...

Finished installing the TCI Pro Super rebuild kit (Summit PN TCI-378900) with a certified mechanic (general transmission knowledge, been through 2 other 700R4s specifically). The kit includes new steel and friction, new forward band, shift kit, etc.

Symptoms:

No reverse but all forward gears work. Luckily I backed it into the garage to work on it.

We take it for a test drive. 1-2 shift at part throttle is super soft...softer than before. That's fine, I'm thinking WOT 1-2 will sheer my U-joints. Engine revs to 4500, hovers, shifts super soft into 2nd.

I run into a mile of stop and go traffic and when it clears, I get in the gas again. It hovers, shifts into 2nd....hovers, shifts into 3rd. I slow down and at the next part throttle acceleration, the trans is slipping.

I pull over and check the fluid. It's full. No signs of leaking at input shaft, servo, or pan. Reverse still doesn't work and now in all forward gears, I have to rev it to 3000 to get it to limp back to the garage.

My friend is thinking something to do with the valve body. Maybe a check ball missing. Maybe the detent cable needs adjusting. Could the torque converter be messed up? Maybe a gremlin snuck in the sprag when we weren't looking.

Please share any thoughts or experiences.

five7kid

iTrader: (14)

If your "certified mechanic" called it a detent cable, you're in trouble.

It's called the "throttle valve" cable, or TV for short, and proper adjustment is critical for transmission operation and longevity. Adjust it properly immediately.

chris718

you must install a pressure gage asap and check line pressure at minimum and maximum tv.post pressures and ill get you a response.

Half-FastRacing

I knew I'd get some sass for the certified mechanic bit...

Thank you five7kid, I called it a detent cable, not my buddy. We put about 5 miles on it without adjustment...I will before it moves again.

Thanks chris718...I will get get you those min/max line pressures.

Adam

FruityOne

No, no, no, no, no!!!!! PLEASE tell me you didn't say you drove it without adjusting the TV cable!!!

There are reports of brand new rebuilt transmission having a severely shortened life because the TV cable wasn't adjusted properly!

Good luck with your transmission. I had some problems with the valve body with my transmission when we rebuilt it. Not bad, it was my first transmission, and it was my buddies 3rd transmission. We didn't have anything but a ATSG book to go by. Gives new meaning to the term "shade tree mechanics"

Half-FastRacing

FruityOne, luckily I have a donor 700R4 if I have done any lasting damage. Thanks for emphasizing the importance of adjusting the TV cable. I will be working on it tomorrow morning, so should have more drama soon.

Half-FastRacing

The pressure regulator valve keeps popping out of the oil pump. The shift kit called for a stiffer spring but the snap ring can't seem to hold the pressure. Anyone know if this is common?

I've ordered a new snap ring but am afraid it will fail also. Is there any other way to ensure the valve stays in the pump? Anything extreme could be considered because I have access to a cheap oil pump should I ruin my current one.

Thanks

Section162

Are you installing the snap ring in the right spot? I think mine popped down twice before I realized it was MY fault, not the snap ring's fault.

Maybe you know this, but there are at least 2 places to install the snap ring where it *seems* like it's in the right spot, but it might not be. Make sure it's installed far enough up in the pump. Without knowing better, I was snapping the ring into a ridge that was a little lower down. Result was no pressure for reverse, and forward gears acting wacko.

HTH

Half-FastRacing

Section162 - Thanks, I will check to see if there are two grooves. The only thing I'm thinking is that if the snap ring couldn't hold the pressure with the piston (and spring) at the furthest setting, I'm not sure it could at a closer (to the pump) one.

Maybe the groove the snap ring sits in is deeper than the one I'm trying. I'll look into it.

LilJayV10

iTrader: (5)

pretty much the same thing happened to me, the boost valve pooped out, because i had it in the wrong slot, it's tough to get in.

FruityOne

Yeah, the TV valve was a PITA to get to stay for a while. I never had it pop out, but it was hard to get in there correctly.

Thankfully the TransGo shift kit instructions are pretty damn detailed.

Problems I had with my rebuild. I messed up in the valve body and when I first ran the transmission through the gears on jack stands I didn't have 4th gear. Later the sealing ring on the servo failed and I lost 4th gear. Fixed it with a new ring and some careful installation.

Transmission shifts awesome now. Before with my old engine it would actually chirp the tires going 1-2. Crappy TBI 350 with TPI induction on top.

But now I got lots more

DigitalMonarch0

Ahhhhhhhh, I hate that snap ring.

I did the exact same thing, but I got frustraited and walked away from it after I got it in that first ridge.

After lunch, and a calming down I farted with it again and won.

Bad memories.

my3rdgen

I sure am glad to see that I was not the only one who did this.

Lucky for me I cought it befort i installed the tranny into the car.

DigitalMonarch0

Yeah... I actually thought about leaving it the way it was and "hoping" that it wouldn't be an issue.

[cliche]

Then I realized that instead of being a dumbass, I should just take my time and make sure that it's done right the first time.

[/cliche]

Half-FastRacing

Thanks a lot guys, I didn't realize there was even a second groove. I have the pan down and will mess with it until it's secured.

RBob

iTrader: (1)

It is not actually a second groove. There is a step machined into the bore which can look like a groove.

What also happens is that the upper piece of the valve assembly hangs up in the case (edit: pump body). This prevents the entire assembly from being far enough into the pump body. So, the assembly bottoms (hangs up), installer sees what looks like the groove, and puts the snap ring there.

Wha-la, boost valve ends up in the pan. . .

Trick is too look and see how far up the groove is. Then, if on jackstands, get a metal rod that fits from the garage floor to the groove, insert valve assembly and use rod to hold in place while futzing with the c-clip.

RBob.

Half-FastRacing

I put the snap ring in the actual groove, past the machined step RBob describes. I've put 100 miles on the trans and it's working great. Couldn't have done it without your help guys - Adam

Half-FastRacing

Three weeks later, and maybe 400 miles, there is a loug whine in first and second gears. When it shifts into third or fourth, the whining goes away. Any ideas on what's going on?

ricktaylor

could be the rubber ring type seal for the 1-2 acumulator could be wore and maybe leaking fluid pressure by, just a guess and the best I can do. The acumulator is right by your valvebody assy., round with acouple three bolts holding it on, you'll see it. If you unbolt it you can take a screw driver and carefully pop the top piece out, you'll see the rubber ring Im talking about. Its a start anyway if you wanna tink with it yourself.

onebinky

iTrader: (1)

I'd say check out the planetary gearset. SOunds like a chipped or cracked tooth on one of the members. Don't remember exactly what the powerflow is, but I think the held member is common for 1-2, and then 3-4, and then R is different. If nobody else knows off the top of there head I can dig out the info for you.

SpeedMetalT/A

Thanks this post really helped. I just built my first trans with the same TCI kit and had the exact same problem. Until now I thought the trans I just put in was completely shot haha.