Time for my 3rd 700r4 =/

[CherryK5]

This one is on its last leg.
My 2-3 shift is slipping hardcore at WOT, it wont even grab third if i dont let off the gas. And my 1-2 shift is starting to slip too. This is the same one that lost OD a couple months ago.

I have a 700R4 out of a 91 burb but it is a 2wd.
How hard is swapping tail shafts?

 

[DeviousK5]

Well... You will have to tear the unit apart... As in almost all the way. Get an A.T.S.G. rebuild book (available at any reputable trans parts suppliers), there are lots of semi detaled illustrations and literally a guide to rebuild, as well as a fairly good guide to troubleshooting if things dont work right the first time. If your that far into the unit you may as well build the damn thing. Its a toss up for a tailshaft swap VS rebuilding yours. If it were me id build your unit, regardless of whether you have a "freebie" used or not.

 

[CherryK5]

Well... You will have to tear the unit apart... As in almost all the way. Get an A.T.S.G. rebuild book (available at any reputable trans parts suppliers), there are lots of semi detaled illustrations and literally a guide to rebuild, as well as a fairly good guide to troubleshooting if things dont work right the first time. If your that far into the unit you may as well build the damn thing. Its a toss up for a tailshaft swap VS rebuilding yours. If it were me id build your unit, regardless of whether you have a "freebie" used or not.

Well i also have the first 2 but i remember seeing somewhere that the 91 and up are stronger?

They usually last me a year or so, i've never done anything but put corvette servos in them.

 

[79rustyk10]

I dont know if 91 or 92 mean anything, but you do want the K case, it has a big K cast into the bellhousing. supposed to be stronger for the 4wd trucks, also they have the cast aluminum inspection cover too vs a tin one.

And if you only get about a year out of them like I did, I would try to learn to rebuild them youself. would save alot of money, and if you have a couple cores you wont really be out anything.

 

[496truck]

Now I thought, someone correct me if I'm wrong, that the 700R4 2/4wd were the same except for the tailshaft housing only. And that is only 4 bolts and an o-ring to swap to a 4wd tailshaft housing. No tailshaft swap needed.

Th350 was the one that needed a tailshaft swap.

Oh, and stop driving at WOT!!! That may save you're trans replacement bills...

 

[DeviousK5]

I cant say with 100% uncertainty as ive built about a half dozen 700-R4s but i am no re-builder , but IIRC the trans as well as the guts are the same from 86or 87-92, remember 93 up is actually a 4L60-E and is electronitly controlled. Lots of parts will swap over internally, such as the later 4L65-e five pinion planetaries, and the illeged hardened reaction shell(they still break all the time and the Beast is the only replacement id use)

Maybe a dedicated rebuilder will chime in for you but i am unaware of any strenght differences from the factory that occured in the early 90's\
BTW corvette servos are overated , one from a 4.3 equpped truck will be just as well, its just not fancy sounding, and you wont be able to tell anyone you have fused corvette parts into your truck.

 

[CherryK5]

I cant say with 100% uncertainty as ive built about a half dozen 700-R4s but i am no re-builder , but IIRC the trans as well as the guts are the same from 86or 87-92, remember 93 up is actually a 4L60-E and is electronitly controlled. Lots of parts will swap over internally, such as the later 4L65-e five pinion planetaries, and the illeged hardened reaction shell(they still break all the time and the Beast is the only replacement id use)

Maybe a dedicated rebuilder will chime in for you but i am unaware of any strenght differences from the factory that occured in the early 90's\
BTW corvette servos are overated , one from a 4.3 equpped truck will be just as well, its just not fancy sounding, and you wont be able to tell anyone you have fused corvette parts into your truck.

Dude my 1-2 shift is brutal. it feels like a shift kit unless im WOT. I love it.


And thats what i thought, with the four bolts and changing the rear of the tranny.

And 496truck, How can i pass someone at less than WOT? Just chug-a-lug past them? Gotta have that downshift and deafening roar.

 

[496truck]

Supposedly the "K" case is a stronger case, just the case not the internals. And the K case came into existence right around 87 or so.

Not a trans expert just going from memory and heresay...

And 496truck, How can i pass someone at less than WOT? Just chug-a-lug past them? Gotta have that downshift and deafening roar.

I know what you mean, but it's not a racecar even if you drive it like one.

Have you had any of these 700R4s rebuilt to take the abuse you give it or do you keep doing used swaps?

 

[CherryK5]

Supposedly the "K" case is a stronger case, just the case not the internals. And the K case came into existence right around 87 or so.

Not a trans expert just going from memory and heresay...



I know what you mean, but it's not a racecar even if you drive it like one.

Have you had any of these 700R4s rebuilt to take the abuse you give it or do you keep doing used swaps?

We own a junkyard. Used. =] We usually have a guy go through them to make sure they aren't trashed though. Then i throw a servo in it and it goes in the truck.

 

[6.2Blazer]

Always have to ask the basics when somebody goes through 700r4's this quick.
1. Is the TV cable adjusted correctly?
2. Did you flush the cooler?
3. Was the torque converter replaced? It's almost impossible to flush all of the crap from a previous failed trans out of this.

Not following any of these procedures will cause a quick death to a new trans.

 

[Greg Ducato]

Basically, the 1987 through 1993 700R4's share the same internals provided they were from a V-8 application.(Truck applications moved to the 4L60E by 1993 but Camaros, Corvettes and some B bodies still used the 700 in 1993). The 4x4 model uses a unique case which will accept the aluminum dust cover and also uses a unique output shaft to mate to the transfer case.It also has a better casting thickness at the face and the rear of the case. Unfortunately, nearly any used 700 today will have over 100K miles on it which is the end of it's usable life cycle. Simply installing some new clutch plates and a band will get you back in service but is a far cry from improving the strength and durability of the unit.A unit with 100K miles will have pump issues, worn hard parts and bushing surfaces, fatigued planetary pinions etc. A qualified professional performance transmission builder can get you a far longer life from the build but it will cost you up front. The good news is it may be the last trans you will need to buy for a while. Keeping the tv cable in proper adjustment and the fluids clean and cool will also help no matter which route you decide to take.

 

[496truck]

That's some good info right there.

The 4x4 model uses a unique case which will accept the aluminum dust cover and also uses a unique output shaft to mate to the transfer case.

And I guess that answers that question.

 

[CherryK5]

Always have to ask the basics when somebody goes through 700r4's this quick.
1. Is the TV cable adjusted correctly?
2. Did you flush the cooler?
3. Was the torque converter replaced? It's almost impossible to flush all of the crap from a previous failed trans out of this.

Not following any of these procedures will cause a quick death to a new trans.

Yes.
Yes.
It was cleaned thoroughly but not replaced.

 

[USSkoval]

When you put another one in, install a big big cooler and a temp gauge. That way it will stay cooler, and when it does get hot, you will know it's time to stop smashing the loud pedal.

 

[obijuan]

th400/208 out of a cucv

http://sanantonio.craigslist.org/pts/2034208108.html

 

[K85 Octane]

I always thought that if you have the aluminum dust cover with support rods going to the engine mounts, that you indeed have a 4x4 "K" case 700r4. Am I wrong? Is there a way to tell which year my 700 is? Cause I have a feeling my truck is pieced together. Slight hyjack, same topic

 

[4X4HIGH]

The 700R4 changed slightly starting in 1988 IIRC and had an auxillary valve body as well as the standard valve body and is a MUCH BETTER 700R4 than the earlier versions.

NEVER reuse a convertor from a failed trans as it will almost always take out the next trans you put it into.

The largest stacked plate cooler you can install will definately help to keep any 700R4 alive.

 

[imiceman44]

I always thought that if you have the aluminum dust cover with support rods going to the engine mounts, that you indeed have a 4x4 "K" case 700r4. Am I wrong? Is there a way to tell which year my 700 is? Cause I have a feeling my truck is pieced together. Slight hyjack, same topic

Correct.
Unless someone drilled the case for the proper bolts on the aluminum cover, I have seen it before.
But you can tell right away when you look at the spot where the bolts go thru since they don't have a bung at the right location.

 

[USSkoval]

The 700R4 changed slightly starting in 1988 IIRC and had an auxillary valve body as well as the standard valve body and is a MUCH BETTER 700R4 than the earlier versions.

NEVER reuse a convertor from a failed trans as it will almost always take out the next trans you put it into.

The largest stacked plate cooler you can install will definately help to keep any 700R4 alive.

I'm fairly certain it was '87 that got the aux valve body.

'85 or '86 was the start of the larger input, 30spl vs. 27spl I think.

 

[rjfguitar]

Supposedly the "K" case is a stronger case, just the case not the internals. And the K case came into existence right around 87 or so.

Not a trans expert just going from memory and heresay...



I know what you mean, but it's not a racecar even if you drive it like one.

Have you had any of these 700R4s rebuilt to take the abuse you give it or do you keep doing used swaps?

I believe my '81 TH400 has a "K" case.