tgilligan

Going to track down a trans leak. What’s a good cleaner to use to remove the leaking fluid in an attempt to start with a dry clean case to track it down? Brake clean?

Seems to leak primarily after a ride or when it’s sitting. Not large amounts, just a few drips. Pan gasket has been changed, shift shaft seal, kickdown and tail shaft bushing and seal as well. It’s wet by the torque converter cover and the underside of the pan so might be blowback so I’d like to get it all clean and dry to try and track it down.

oldcutlass

Have you checked the dipstick seal?

therobski

Once upon a time, my tranny had that pesky little leak, no biggie but I don't like leaks under the car because eventually it gets the underside all dirty. So I changed the pan gasket still leaked that tiny bit. A good friend of mine suggested I pull the pan again and put a straight edge on the matting surface and make sure it was flat. Nope, it was just a bit warped around the bolt holes. He said that he's seen that many times because in the past someone turned those pan bolts to tight and over time the pan tends to start leaking because the surface is no longer completely flat. He had a long steel anvil at his shop and flattened it for me and bingo.... If all else fails there's an idea. This was for my 200-4R in the F-85 and I was real close to running over to Summitt and drop $230.00 for a Hughes transmission pan-not...

matt69olds

Use brake clean to clean the oil and crud. Get some air conditioning oil with the fluorescent dye, add a couple ounces to the fluid. Take it for a drive, then use a black light to search under the car for the glow. The dye will make the leak obvious enough that Stevie Wonder could find it.

tgilligan

I did and the o ring was intact and doesn’t appear to be leaking.

tgilligan

I saw some pans with drain plugs on Summit for less than $100. Was thinking of replacing with new gasket to be safe. Any thoughts on the aftermarket pans from Summit?

tgilligan

Perfect thanks. I’ll pick up the dye and a UV light and hopefully track this down. My luck it’ll be the main seal or pump seal. If it is that’ll be my excuse to replace the torque converter to a higher stall.

Greg Rogers

I had a small but relentless leak on my T350 I couldn't find. I had a wasp nest in my eaves of my house at the same time and I had bought some type of insect killing dust and a duster. Ahh... I decided to completely fog the underside of my transmission/ torque converter and recheck in a couple days. Yep, found it, the ATF coming out of the selector shaft seal made a nice small wet trail out of it, Sounds crazy but worked great. Good luck ,they can be hard to find!

tgilligan

Update Sat 5/30:
I used some fluorescent leak detection dye and added to the ATF and took for a drive. Got the trans up to temp and pulled back into the driveway to check for any leaks. As I suspected, I didn't see any active leaks coming from the obvious spots, in fact after cleaning the trans prior to the drive, it looked clean and dry. For reference, I've already changed out the kickdown, tail shaft seal, shift shaft selector seal with new. I then checked all those spots first to rule anything out. Then I checked the speedo housing/cable, dipstick tube, pan, trans cooler lines, modulator and the other open areas......dry. I had long suspected that it primarily leaks after shutdown and longer periods of it sitting (few days) so I'll go back and check with my UV light again at night after it cools to see if anything new shows up. The only single spot I saw was the bottom bolt of the plastic torque cover had a small dot of dye showing, leading me to believe it might be either the torque converter or the pump seal area.

Any other thoughts/ideas? I was hoping it would be something obvious or at least clear to get to but it's looking more and more like the trans is going to have to get pulled and possibly rebuilt with new seals.

Help please!