ATF leak from 700r4

[Ratau]

I found that my Blazer

[CleviteKid]

The front seal where the torque converter slides into the tranny is a known wear item on the 700R4. My sources recommend that every time the engine and tranny are separated, it is a good idea to replace that seal, even if it is not leaking yet.

The bad news is that you will have to drop the tranny and pull the converter off to change that seal. If you do it yourself it takes a lot of time and muscle power, but not much money.

Dr. Lee :cool:

[Ratau]

Dr Lee

Is it a O ring or a oil seal and could you give me a part #

Thanks

Danie

[TimK]

When you have it apart carefully check the snout (stub shaft) of the torque converter where it slides into the transmission, specificaly in the area where the oil seal make contact with the shaft. Run your finger nail over the shaft surface and check for anything that doesn't feel absolutely smooth. Sometimes the snout will fracture causing a small (very small) lip where the seal will let fluid past. Depending on where the TC stops may cause the truck to leaks a little or a lot when parked. A small fracture might even look like a score mark.

TimK

[NH2112]

The converter on my 85 K10 developed a crack where the pump drive was welded to the torus, and it was amazing just how much ATF that spinning converter could throw! It was barely visible to the naked eye upon examination, but a couple moderate raps with a hammer made it easier to see. I'd originally dropped the tranny to replace the seal, but that obviously didn't stop the leak. Between that, and replacing the flexplate maybe a mnth earlier, I got very good at dropping that tranny - I'd have all the tools lined up in the order of their use before beginning, air hose snaked under the truck from the front, and my homemade cradle mounted to the floor jack. Elapsed time from turning the first bolt to the jack lowering to the floor with the tranny on it was 40 minutes. I'm sure I could have knocked some time off that, but an SM465 went in in place of that 700R4 so my record still stands. tongue.gif

[catmandoo]

i was driving down the road years ago and a buddy was following me and he said it poofed out a big cloud and about 2 miles later she stopped moving,refilled with fluid and it was running out as fast as i could put it in.pull the trans and the front snout on the converter cracked and man they can throw some fluid