The Stovebolt Site Forums The Shop Area Driveline 700r4 question

I spent the day crawling over and under vehicles in the salvage yard looking for a 700r4 transmission. I found two that might just be a 700r4 but I am not 100% what I am looking for. Here are the codes I got off the right side pad. #5BWD235J and #8 ZM216A. Is there any way of telling if they are truly 700r4?

Both have the square pan, 700r4/4L60. I just want to make sure i am getting something I can use.

700R4 /4L60 basically same transmission, but you do want to find one built after 1984. Also, 1983 -1989 (I think) they called it a 700R4 then in 1990 started calling it a 4L60.

Then they came out with a 4L60E which used a computer to do the shifting.

Roy is correct in saying to find one built after '83/'84 as the later ones have, if my memory is correct, better valve body system.
I think the remanufactured, or replacement transmissions do not have the numbers stamped into the edge of the tranny to known for sure what year they are. There are simply no numbers.
I found out the hard way.....I bought a core that turned out to be the early model....no numbers. A good tranny friend of mine rebuilt it anyway and it has served me well but if I had it to do now I'd know better than buy it to begin with.

...and for anyone simply "buying a core" be aware that if the fill tube is loose, or gone, the bottom will be rusted and beyond cleaning up and will need a new valve body. Common problem with junk yard trannys.

There was also a change in the pump from the '84 and earlier to the '85 and newer. The early 700r4s have a 5 vane pump, the late ones have a 7 vane. The pump has a major issue in the early versions.

700-R4 / 4L60 will have a throttle valve cable coming from behind the fill tube, 4L60E has same pan shape but no T.V. cable.

Easiest way to find what you need is to look for one with a TV or "kickdown" cable. A 4L60E will require input from a computer in order to work. I assume you don't want that.

The best place to go looking for a 700R4/4L60 is under a V6 engine S-10 pickup. Ditto on using the midrange transmissions- - - -the early ones had growing pains, and the later E-series transmissions need a computer.
Jerry

Yes, I want to keep it as simple as possible so no computers. One of the transmissions is in a v6 Trailblazer the other in a Rear wheel drive Mini Van. Not sure what the engine was in it.

Be aware that the 700 is extremely sensitive to TV cable adjustments, so the bellcrank at the carburetor must duplicate the geometry of the original installation as closely as possible. The reason the name got changed from 700R4 to 4L60 was to get away from the terrible reputation the 700's got for shift problems and premature failures. Virtually no change was made to the actual transmission- - - -they just "changed the name to protect the guilty"!
Jerry

It's worth noting that there are 2 different bellhousing patterns used in the S10s. The 2.8 V6 S10s have a different pattern from the 4.3 V6 models. The 4.3 is the same as the V8s and the 3rd generation inline 6.

I don't think I've ever seen a 2.8 engine mated up to a 700R4. You're right about the 4.3L V6 bellhousing bolt pattern- - - -it matches late sixes and all the V8's I can remember.
Jerry

In regards to the 700R4 adjustment. Jerry is dead on about it being sensitive. I have never got the one in my 37 the way I'd like to have it but after two or three days and multiple times getting in and out, with a helper, I finally got it "close" and gave up.
Sense the 37 was such a booger I convinced myself I need a kit from here http://www.tvmadeez.com/ez_solution.php
I used it on my panel with the 700R4 and the panel was a "breeze" to dial in and works very good. The only way I'll know if its really any good is try one on the 37 just to see! ....also I have the same carb on the pickup and panel.

....A bit off topic, but as information, while discussing the S-10 the alternator/AC/PS brackets on the 4.3 will bolt to the Chevy small block and you can run a serpentine belt system. Just buy a 4.3 water pump as it turns in reverse and you have a cheap serpentine set up. I love the one on my panel and didn't spend hundreds on the pulleys ect....

Be sure to use the 4.3 fan as well- - - -otherwise you'll get a no airflow situation at highway speed when the fan can't push the air forward against the ram air coming through the radiator. That happened to a friend who put a Vega fan on a Chevy II 194 engine.
Jerry

Now you have me questioning my sanity. The serpentine set up on the late 80's to mid 90's 350 also used a reverse flow pump and fan.

Looking at a parts catalog for a 1992 Chevy S-10 with 4.3 and Chevy c-10 with 5.7 they use the same water pump.

Now that you have me thinking about it, I don't think I've ever come across a 2wd S10 2.8 with the 700R4. However, I have seen quite a few of them in the 4x4 models with the 2.8. My '85 S10 Blazer 4x4 has the 2.8/700R4 combo. It's actually a very good setup, too.
I have come across the TV cable issue. With the OEM setup, it's not hard to keep adjusted. Another thing to watch for s the governor gear. They're a high wear item, and when worn, will make it shift late. I've had to replace the one in mine a couple of times over the years.

It's also important to note that the V6 700R4's, either the 2.8 or the 4.3 versions, used lighter duty clutch packs than the V8 models. There is usually one to two fewer clutches and steels in each group on a V6 trans. They can be modified to accept more, but it requires machine work to the face of the piston in each pack. They will still work behind a V8, just don't be surprised when they burn up prematurely.

One of the reliability tricks we used when building 700's was to install the Corvette clutch drum in the overdrive position. It had one or two extra clutch plates and made the transmission much more reliable. That modification, and getting the TV cable adjusted so the trans didn't toggle in and out of overdrive solved a lot of the premature OD clutch failures.

RUN- - - -do not walk away from any so-called mechanic who suggests installing a shift kit in any automatic transmission!
Jerry

The Corvette 700's would also allow full-throttle operation in overdrive. Passenger car and truck versions would not. Hence the extra clutch packs in the vette version.