A couple of years ago the front planetary in my TH700R4 spit out a thrust washer but rather than buying a used $25 planetary I installed the 2002 and later AC Delco front and rear 5-pinion planetaries (about $300 for the pair plus the required front hub and Torrington bearing). The later planetaries offer about 25% more strength because of better materials (I believe they're investment castings). Then two months ago it suddenly lost oil pressure because the input to output shaft seal failed (see picture). As I happened to have a new seal in stock I put it in then found there is a better seal available that is made from Viton and costs about $2.50. I bought two of them and the next time I have it apart I'll put one in.

The TH700R4's were originally designed to be used behind the 4.3 liter V6 so they couldn't handle much over 300 ft/lbs of torque. But over the years they were steadily improved and now days they can be built to handle 500+ ft/lbs of torque for little expense using 4L60E and aftermarket parts.

 

I got so tired of pulling my failed 700R4 that I went to a full race 750 or 800 hp rated model with 9.5 inch Vigilante TC with 3800 stall.

I used the biggest B&M cooler and 1/2 inch SS braided lines. You change the 3/8th adapters on the sides of the aluminum case

 

My '88 model will handle about 550 to 600 ft/lbs of torque so its more than enough for my 400+ horsepower 454". People have bashed the TH700R4's because of failures; not realizing they weren't intended to be used behind high torque engines. As time went along G.M. continually upgraded them to handle the increasing torque demands and most of the later heavy duty 4L60E and 4L65E parts can be retrofitted into the earlier '87 and up cases. Several months ago I bought a used 4L65E reverse input drum for my '82 and it dropped right in.

 

No matter what you do with the 200/700 OD units your way better off spending the extra and going electronically controlled 60e or better . The biggest failings of the units is control and the proof in my statement is a 60e will go 200k easily a 700 or 200 never will no matter what you do to them ..

 

In my nearly 20 years and over 100,000 driving miles of 700R4 experience. No stockish or even so called high HP modded 700R4 can withstand power braking with slicks on a sticky drag strip even with only a 355 ci small block. I even had a 4.11 rear to make it easy on the tranny to take off. You would be lucky to make 10 1/4 mile runs My original TCI or B&M out of Jeg's high hp lasted one run. and they repaired it even stronger and it lasted about a day at the all vette drags and I limped home.

I just bit the bullet and spent $3-4K for the 4th gear only manual switched lockup 700. Then I never had another problem. It is still running today in another forum members roller cammed 406 sbc.


Then I got smart and went to a tko600 with all the bells and whistles with a 11 pound aluminum fly wheel.

 

An 11 pound aluminum flywheel? That's a circle track racing flywheel.

Properly built a TH700R4 will withstand years of drag strip abuse so if yours were failing in that short of time there was something drastically wrong with them. Severe duty racing frictions are readily available and with proper pump pressure they won't slip unless the engine's torque exceeds their ability to hold.

 

On one hand you say bullet proof then point out the failings of the design.

Drag race transmission ?? Hardly suitable unless your taking a mild daily driver to the track occasionally . .

 

Years ago I installed my 406, and immediately blew the th350 that had lots of miles on it, and decided to jump on the bandwagon of OD transmission swaps. Did a BTO 700r4 level 3, which was rated at 600 horsepower...........Lasted one week. I babied it for the first several days, checking for leaks, shift quality, and then on the Friday trip back home....I nailed a second gear upshift at 7000 rpms, and heard an awful crunch. Trans was toast. Of course BTO backed out of the warranty, and I was forced to have a local shop make repairs.

This transmission lasted one year,..the whole time was driven like Miss Daisy,..because I had no faith in the trans, and no extra cash to fix it if it blew again. It blew again..........well just quit shifting.

I went to the time tested th400. Full manual vb, 3000 stall with antiballoon plate, and never looked back. Shifts like right now, no matter what rpm, and gave me that feeling of confidence back. Now I do not drive like a maniac, and beat the snot out of it, but in my mind know that I could, and not hurt a thing.

Funny thing is when I was considering the OD swap, a lot of forum guys had already done the same. Now it seems most everyone has gone to Tremecs..........Makes me wonder why.

 

The biggest problem with GM O/D automatics with TV cables is that the cables are rarely adjusted properly. And, if not set up right, the tranny's clutches are quickly 'toasted'.

Next biggest problem is leaving the lockup system in ON mode when pouring the power to it. Lockup clutches have very little torque handling capability. So, for 'power' use, voltage to the L/U system needs to be turned OFF, so that clutch will not be active. A simple toggle switch placed in the power feed line to the L/U clutch is all that is needed.

 

When the lube seal fails like that I'd take a good look at the stator support bushings.
They are probably bad.

 

I dont know enough 'bout auto trans to know what a manual vlv body or a transmission vlv (TV) cable does/do.

But my level 3 BTO 4L60E is starting to slip and i cant change the shift points either. This is my '94 Z28 BTW. I would like to go to a manual shift 4L60E and a B&M ratchet shifter with reverse LO so i can bang the gears. Dont know how to go 'bout this. Maybe should post in the C4 section but seems some guys here are knowledgeable on this. Ive read the 4L60E needs internal parts/mods to convert to manual shift but no one it elaborating on this - though i can find some google w/s that do.
Another issue is everyone on the camaro forums say dont switch to manual shift 4L60E - leave it electronic. But in tunercats software we lowered the shift points using mph (because tunercats uses mph not rpm) to pretty low numbers. But the car still gets to 5000rpm and slowly walks up to 6000rpm where it shifts. Im using a short cam and it done by 5500rpm - maybe before 5500rpm.

Manual shift a 4L60E anyone.

 

I'll toss my 2 cents.

My buddy owns a transmission shop here in Fullerton.

He built me a 700-R4 using the later truck housing, and all the goodies inside. It has hydraulic lock up, and no wires. It took 4 tries with governor weights and springs to get it where I wanted the shift points.
My only issue was on a Vette run in the mountains, it got hot and puked 3 qts of fluid.
I installed a tranny cooler, and since then, in 12 years, not ONE issue.
I MUST state my 81 is only 200HP, so that must be considered.

One more statement. My buddy rebuilds the BTO units all the time. He says they build trash, and would like to wring their necks.

 

You don't want a manual valve body in a car you drive all the time. A properly built 4L60e will last a good while and take some power. The only ones I trust to build them is RPM Transmissions in Indiana. They have an easy shipping program and they handle both ends of the shipping for you.

Depending on how much power your car makes will determine which level trans you need. I'd buy a Level 5 for 600hp or less. They are pricey but will take abuse. Get the trans tune from RPM as well..

DONE.


LOTS of 4l60e "Builders" out there... But it pays to go with a proven product. RPMs race reputation is proven.

 

That PCM uses both rpm and mph in 2 separate tables to set the kickdown shift points. You have to reach both the MPH and the rpm before it will shift. I'm able to tune both my kickdown and part throttle shift points just fine using Tunercats so you're doing it wrong.

You probably also raised the "max line pressure" parameter from 90psi to a higher number which is a very bad thing to do because that just lowers your line pressure which causes it to slip.

A full manual conversion would likely run the transmission at full line pressure so expect hard shifts and a short life between breaking hard parts.

 

ThX lion your quite timely and helpful even though u made the wrong assumptions. That separate table(s) issue may well be my problem but it was my tuner that set it as i dont even have a cable yet let alone software and used any of it. I did get around to buying an older laptop with a RS232 port though but havent sprung for the tunercats s/w yet as im still sorting things out - im sure u have priorities also. As far as your line press assumption i didnt touch that either though i suspect u are also correct that it is to high. I guess i can look into those once i get the software. Thx for the tips though.


Thanks aj for the recommendation. RPM wants $2400 for that level 5. W/shippin thats close to a 4L80E conversion w/rebuilt 4L80E or at least a TH350 conversion. Im thinking the TH350 is an option also as gas prices go down. Hi-po TH350 prices are as a cheap as it gets and i can shift it manually. And the tighter gear spread matches my small cam much better. Ok so ive looked a few things up and u dont need a TV cable w/o an OD trans - one less item. And i dont need a lock up TC either with a 3spd. I can run manual vlv body or a auto/manual vlv body so i can bang the gears or let the trans shift itself.
Well i should just get my shifting problem fixed first. But i maybe able to get the swap done for less than a hi-po 4L60E but i have deal with all the headaches - computer, driveshaft, trans mount, cooling lines, shifter.

Ya know a local F-body owner that used to race bracktes w/NOx motor here gave up on the 4L60E and the TH350 also. He runs a power glide now and says it matches his NOx motor well enough and hes tried of R&R the trans every season. Im not there in power by any means. But i understand his line thinking.

Yea i have a long story bout BTO as they seem to be kinda hot or cold. Good deal and good product or good deal and not as good product. Well i think every shop has workmanship problems on Mondays or Fridays. I did get to see their shop and good parts that go inside my trans. BTW BTO has a slick little sliding adj trans mount for a 4L60E to TH350 conversion.

 

One thing I note here is that no one mentions the sunshell which is a famous weak spot , the 700 I built for a 350 powered 8000 lbs motor home got a super heavy shell, called the Brute or Beast and then a plastic bush/thrust bearing replaced with a torrington local supply house carries all this stuff...been maybe 6 years now, so far so good....

 

Thx Gene, funny u mentioned the reinforced Sun Shell as that is one of the hi-po parts BTO showed me that goes into a level 3 4L60E. I dont think i have a sun shell problem. Ive also been told to shift into 1st gear manually as this engages more clutches (or something like that) then as the car picks up speed return it to drive.

 

OK, so you wrote " in tunercats software we lowered the shift points" but you had no involvement. So sorry I assumed you did......

 

Oh geeze lion, he lowered the mph point because i asked for a lower shift point and i got to look over the guys shoulder and actually saw the table. And your advice is very helpful but u add fault finding to it for some reason. No i dont want to fight or argue but if i have to explain and defend myself in every post maybe u should take your help somewhere else for the sake of the OP's thread and i can struggle on w/o your advice.