I had my 700r4 rebuilt by my buddy(GM tech) not long ago. I put about 30 miles on the rebuild when driving down the around 35-40 mph my 5 pinion rear planetary gear from tci transmission seized up and cracked in half. Locking my rear tires up causing me too skid and hop until it strips and my car barely moves off to the side of the road. Cracked my transmission case and stripped my torque convertor. What would cause this to happen? Was it just a defective peice?

 

was it an aftermarket 5 pinion planet or a factory one?

 

Aftermarket from tci transmissions. Stage 1 kit

 

https://www.thirdgen.org/forums/tran...00r4-weak.html

Check post #5 from the thread linked above.

 

If you do some reading, you'll find that the aftermarket 5 pinion planets are actually weaker than the 4 pinion OE planets. They are made either in Korea or in China and they generally sell for about $100-150. They are also prone to grenade when placed behind any kind of power. A new OE 5 pinion planet from GM sells for around $240. You get what you pay for. Dana from Probuilt Automatics also specifies the viton input shaft to output shaft seal be used to prevent pressure loss and lack of lubrication to the rear planet. The o/h kits still come with the crappy hard plastic piece that GM did away with because it leaks and causes rear planet failure.

 

Thanks guys. It really blows to trust a company with a big chunk of change thinking you're getting quality parts and you get screwed over by cheap communist parts. My buddy ordered the same kit in his 500+ hp/tq bird I'm gonna let him know about this. My whole trans was filled with metal. I have to go buy a whole new trans from a salvage yard now. I do not reccommend tci trans's stage one kit any more.

 

For parts and tech advice, I recommend working with Dana at Pro Built Automatics. He knows more about building a bullet proof 700R4 than anyone else I've talked to. One source for the OE 5 pinion rear planet is PATC. They have a special price on them right now of $179. I'm going to be getting one too. I just built my trans a few months ago and while I am very pleased with its performance, I plan to go back in this coming winter for a few upgrades. Now that I am familiar with the unit, swapping out the rear planet will take a few hours total including R&R.

 

5 pinion planetary is overkill the stock one works just fine

 

I run 420hp through my 700R4. It had the viton input shaft/output shaft seal and the rear planet oil slinger was in place. When I had the unit apart this winter, I noticed that the gear lash in the rear planet was alot greater than in the front. My research has led me to the conclusion that the rear planet leads a much rougher existence than the front. I shift at 6,300rpm and while I drive the car like a grandma most of the time, I built her to take a pounding and I don't sweat pounding on her whenever I feel like it.

For racing or occasional hard use behind 400+hp, I think that the OE 5 pinion rear planet is a good investment. If you aren't going to spring for the OE 5 pinion, use an OE 4 pinion. Do not use an aftermarket 5 pinion.

 

Well I had built the trans with what I thought oe or better parts. I had planned to put a motor behind the trans and a good rear. Since that hope and dream has turned to a nightmare.I've rebuilt the trans twice this would be third if the case wasn't destroyed. First time having 100k miles on it. 2nd time made a rookie mistake didn't clean valvebody and that smoked 2, 3-4s. This time being out about 1.2k on a trash trans. Now I'm buying a prebuilt for 500 and 2 year warranty with 400 hp rating. Owned the car for 13 months its been driveable 3 weeks. Kinda done with the whole car and thinking about selling.

 

Sorry to hear of your bad experiences. I have spent way too much on my trans also. I put the Transgo 2-3 shift kit in the stock unit when I first built the engine. That lasted 6 months, which was not bad considering the unit had 107K on it. Then I bought a TCI prebuilt that wasn't really what I wanted so I had it redone by a trans shop in Portland. After three attempts, they finally got it to hold together and work pretty well for about 22K miles. This unit I built works very well and aside from the rear planet that I will deal with next year, it's rock solid(knock on wood). We do the best we can and then, unless you're a master like Dana, luck kinda decides the rest. Good luck with the unit you bought. I hope you don't give up on the car.

 

I'm back and forth with idea considering I saved this bird from the yard. I've literally replaced everything except the interior and the motor. All new suspension, rims, rear, tires, rebuilt the headlight and hatch motor. New hood and hatch supports. Hopefully I'll drive it without anxiety and get back into it.

 

Yeah, cars can be money pits. I love mine and have done everything to it short of a bit of body clean up and paint. Still, even as I enjoy driving her, I think about what's next. Tubular front X member, full dual exhaust, 377 or 406(still not sure which), new rear to handle 377 or 406. Honestly, as long as I can still hold a wrench, I guess I'll never be done. (Please don't tell my wife.)

 

Got a salvage trans with 92k miles and finished putting it in today it drives just fine just has a truck governer I'm going to switch out with my firebird governer when i get around to it. The trans is shifting strong so I'll see how things go.

 

I agree ..but there can be more worse things you can spend money on lol If i got a nickle for everytime i told my wife this is the last part im going to get and im done lol

Stay motivated as long you learn from the experiance ..i had a beater RS anything and everything went wrong blew a head gasket and trans lost OD and 3rd on freeway and only had 1st and 2nd with very bad slipping and many other stories lol .. even with all the headaches i still miss that car ..

Trans company that stand by there work that i ive and buddys dealt with

http://www.performabuilt.com/
http://www.700r4l60e.com/

 

you can shop a few tranny shops for OE GM 5 pin planets.
picked up Factry GM units front and back new in boxes with everything all the small parts
for $300.. just shop

get to know what the GM made parts look like also.. you can pick them out in a pile of parts when ya know.