please answer quick question on 700r4 rebuild

alright i need to rebuild my 700r4 in the somewhat near future. Problem is this is my daily car, for money reason i want to attempt to do it myself. Could i buy any junk r4 from the boneyard, and replace all it's internals with the pro-built stuff, take my time, do it right then one weekend bolt my "new" transmission in? or is there somethings i need to look for in the junk tranny, specific years? the car is an '89 IROC

Originally posted by camarocruzin
alright i need to rebuild my 700r4 in the somewhat near future. Problem is this is my daily car, for money reason i want to attempt to do it myself. Could i buy any junk r4 from the boneyard, and replace all it's internals with the pro-built stuff, take my time, do it right then one weekend bolt my "new" transmission in? or is there somethings i need to look for in the junk tranny, specific years? the car is an '89 IROC

Just get one thats from an 84+ car so its the 30 spline input shaft.

thanks a lot that's what i needed to hear

josh

Originally posted by camarocruzin
thanks a lot that's what i needed to hear

josh

One more thing Im not sure Im sure somebody will come along to say for sure shortly. But in the 91-92 models they went to an electric speedo. So the R4s out of those may not have the hole in the back for the speedo cable.

forgot to add is this financially smart?? how much would a junk trans cost? i have a th 350 and a th400 in the garage..would either bolt in while i work on my r4? how about the shifter seeing how there would be no od....?

They both require substantial modifications, including fabricating a crossmember and having your driveshaft lengthened. I'd say getting a junk trans (prolly $100 or so) and building it is a great idea. Just make sure it has the right input shaft and the right size speedo sender hole (Darth is right the 91-92 Camaro's have a larger electronic sender....I believe they started using them in '88 in the T/A's.)

not sure about the shifter. I think it would work just the dial would be in accurate. You can bolt in one of the others with a longer driveshaft and a cheap kit. The one for the 400 is around $100, but the 350 kit is substantially cheaper I believe.

Are they that cheap? I was thinkin more like $250.....

Originally posted by TheGreatJ
Are they that cheap? I was thinkin more like $250.....

Somebody had a link for a kit I think from summit about two weeks ago when another thread like this came up. Ive been keeping track of things like that cause Im going to a TH-350/400 when I drop my 406 in. I dont drive everyday so the hassle of the 700-R4 weakness and T.V. cable isnt worth it to me for overdrive

I think the 400 kit was like $112. But you have to take a die grinder to you torsion bar to get it to work I think

thanks for the quick replies i'll look for a trans one of these days then when i can run to the boneyard, the rebuild can be done with most hand tools right, just a need a dial indicator? i plan on picking up a book and a pro-built rebuild kit and take my time and hope to god that i do everything right


btw the th 350 i have is a long tail so i wouldn't need a new driveshaft correct?

No Problem. I wish somebody would make a few replies on my distributor post lol. Its been up twice as long as this one. But its all good. :D

I almost replied to it but then I looked harder at the pics and realized I was gonna say something that was all wrong.

Originally posted by camarocruzin
thanks for the quick replies i'll look for a trans one of these days then when i can run to the boneyard, the rebuild can be done with most hand tools right, just a need a dial indicator?

yes you will need a dial indicator to check end play, and you will also need a pump puller (a slide hammer will work also) and you will need a good set of snap ring plyers. on mine i also needed a huge set of channel lock plyers to get the servo cover off:D

In Orlando FL junk yard tranny's are $300.

If the tranny came out of a 3rd gen, great, it'll bolt right in - but if it didnt, you'll need to swap over the tailshaft housings for the torque arm bracket - thats no big deal at all. Make sure it's a 30 spline, and try to get one from some sorta "old folks luxury car" so that it hasnt been beat up on too much so you don't end up replacing too many hard parts. Also the shifter lever on the transmission may need to be switched too, the tranny I got from a junk yard (cracked my stock 700R4's case :D ) came from a column shifter car so the lever was totally different.

As for a TH400 or TH350, they will bolt right up, Spohn.net sell a $100 transmission crossmember that'll bolt right up, but as someone else mentioned, you'll also need a new driveshaft, Spohn also sell these for $300 ish, or you can get a Lingenfelter for I think $400, or get one made at a local driveline shop for maybe $150-200 or so.

Originally posted by Nitromethane
In Orlando FL junk yard tranny's are $300.

If the tranny came out of a 3rd gen, great, it'll bolt right in - but if it didnt, you'll need to swap over the tailshaft housings for the torque arm bracket - thats no big deal at all. Make sure it's a 30 spline, and try to get one from some sorta "old folks luxury car" so that it hasnt been beat up on too much so you don't end up replacing too many hard parts. Also the shifter lever on the transmission may need to be switched too, the tranny I got from a junk yard (cracked my stock 700R4's case :D ) came from a column shifter car so the lever was totally different.

As for a TH400 or TH350, they will bolt right up, Spohn.net sell a $100 transmission crossmember that'll bolt right up, but as someone else mentioned, you'll also need a new driveshaft, Spohn also sell these for $300 ish, or you can get a Lingenfelter for I think $400, or get one made at a local driveline shop for maybe $150-200 or so.

So thats all you need other than the driveshaft is a crossmember?

Oops almost forgot about the B&M Torque Arm Mount kit for a TH350, $79.99 Jegs part# 130-30299, unless u buy a $375 spohn torque arm that comes with the crossmember :D And if you can find a junk yard driveshaft off a 3rd gen with a 2004R transmission then you can use that for the TH350 also.

I got mine rebuilt by www.rosslertrans.com and they came recommended by Lingenfelter. Their tranny lasted 3.5 years behind my 383 with me beating on it before needing a new sun shell gear or whatever it is.

They took my stock 700R4 and rebuilt it to shift at a higher point and with a shift kit all in it.

Changing shift points is just a matter of changing the springs n weights in the governor, should try and get shift points around 200rpm past your peak horsepower for a smooth accellaration - im sure you've got yours setup correctly, but just for those who don't know - there's people running around with 4500rpm peak power saying "yeah my car revs out to 5800rpm!" just cuz their shift points are way too high - so they have 1300rpm of "dead revving", then when it finally shifts, the car starts to pull again.

Use the 1988-early1993 cores only. They come with the bigger style sprags, forward accumulator, and 30-spline input shaft.