The subject says it all. I'm thinking about, rather than putting a V8 in, just drop a used 3.4 in. But if I do that, I'll almost certainly have to rebuild the tranny after a short while.

The body is pretty clean, just some minor rust, other than that the body is fine. Hence the reason I will probably keep the car. How many miles on average before thinking about a trans rebuild?

 

For me,
I drive everything until it drops.
If it moves, might as well save a few $ until I'm forced to do something.
I have several vehicles I rotate thru until pure vehicle death.
When the tranny fails is when I do what needs be done.
That theory has worked out well for my needs.
BUT SOME ENGINE/VEHICLE PARTS SURE HAVE LOUSY TIMING OF FAILURE!
IF only 129,000 miles on current engine, swap in new timing chain, rebuild ignition system & keep it going.
Plan on buying a crate engine, as it sounds like you've got miles to keep going. Score the necessary 3.4 injectors anytime.

 

Unless it is feeling mushy and shifting sloppy there is no point in rebuilding your tranny. Just put in a shift kit, and a tranny cooler and you should have trouble free operation for a long time to come.

 

Post-87 700r4's lasted a lot longer than Pre-87... and the newer the 700r4, the more design improvements were made by GM. But ignoring that, how's the fluid (feel & smell)? When's the last time you changed it out? Was there excessive metal in the pan, or "shadows" in the pan that usually signify burnt clutches? Have you adjusted the TV cable recently, and if so, was it far out of adjustment?

 

the 85 camaro i had has 186K with no rebuild, my 89 has 149K and its slippin like crazy and all other problems

 

Hey I know how you feel; my original trans crapped out in Jan '97. Had it swapped out for a pre-rebuilt unit by the crooks at Lee Myles for $1300, and it lasted two years before taking a crap. By then, I had a friend of a friend who was owed a favor, and he cashed it in to get my trans rebuilt for me for $380. (I had to drop the blown one out and put it back in myself). And -THAT- one has problems, too.. in fact, it's been slipping in 2nd gear (not the shift itself, it slips out of gear!) for the past two years. I'm surprised it's still working! I plan to rebuild it myself, because hell, if nobody else could rebuilt it correctly, how much worse could I do?

And the second guy was supposed to be a master technician for trannies!! Go figure.

 

or you could do what i did and buy one out of a salvage yard for about 200 with no core charge. and a 30 warranty...knock on wood i havent had any problems yet and its been a year of hell on the trans. if you do change the trans your self. be ready it wont be to much fun by yourself and the car on jackstans .....bump that it realy sucks!!!!!!!

 

where are the tranny lines that go into the rad, i just scored a truck tranny cooler and i'm gonna put it in , and if a tranny makes a errrrrrrrrrrr kinda sound but still shifts do you guys think its in need of a rebuild?

thanks

 

if u put the trans cooler you will have to find a diffrent radiator or find a way to plug that one up just to let you know

 

u can get plugs for the radiotor in lowes or home depot, i believe they are 1/4 threaded plugs, u will find them in the plumbing section, ask one of the people that work there they might beable to help u find exactly what your lookin for

 

You don't need to plug up/disable the factory trans cooler! In fact B&M recommends you use their trans cooler in-line with the factory unit; that's what I did.

From the trans, fluid flow goes into the factory cooler, then into my trans cooler, then into my remote trans filter, then back to the trans.

 

thanks guys, my dad told me to do it like tomp said,

 

(little childs voice) tomp my hero i love him!!! just kidding

 

Tom, when it comes to rebuilding 700R4's there is no such thing as a master technician LOL

the general consensus is that if its not done 100% correct and perfect, its toast

its a very poorly designed transmission, for one because it was designed with an electronic valvebody in mind, but that was put off for 10 years

i took my 700R4 with me to school and pulled her apart

the sprag "ate" notches into the transmission case, qualifying this trans as FUBAR

the clutches and 2-4 were burned beyond belief

also, its very difficult to re-assemble

and when re-assembling one, you must have the clearances perfect and seals perfectly fitted

most "master techs" that i know, tend to shy away from touching 700R4's when they have the choice

 

Yeah, the guy didn't want to rebuild it, but he did it as part of the favor he owed. What's funny is, people usually forget that when the TH350 came out, it was also deemed garbage, and hard to rebuild- just like the 700r4. People were dumping their TH350's out for Powerglides. That's why I don't really see an excuse for a trans tech to complain about a 700r4; they just have to learn more.

But you're right, the early 700r4's 83-84 were garbage... 85-86 wasn't far behind! That's why I'm going to try and score an 87-up 700r4 to rebuild.