changed ATF & filter, and now it's leaking

[DesertDually]

This just recently happened to my 1978 Mercedes-Benz 300CD, which previously didnt leak a drop of transmission fluid. As the car is a semi recent purchase, I am in the process of going through and changing all fluids, everywhere. The ATF that was in it looked a little "off color", but definitely wasnt the worst i'd ever seen or smelled. Put the new filter & gasket in and all was well. For a few weeks anyway. Now I am getting a few quarter sized spots of ATF underneath the front of the trans when I park the car after driving it any distance. A mechanic at a local indie Benz shop put the car up on a lift & said it is likely the front seal (or front pump seal?). The transmission shifts just fine, like it always has, no complaints there. But this new fluid leak bothers me, obviously. I am going to take an educated guess here & suppose that the addition of new ATF somehow dislodged some dirt or debris around that seal, thereby enabling the leak. Is there any "magic additive in a can" that may possibly remedy this situation? I am pretty sure that other folks on this forum have dealt with this exact issue at some point in their life.

 

[oilboy123]

Auto-RX is worth a shot. Not a sales guy for it, but it's done some wonderful things for my taurus. For about $25 for a bottle it beats pulling a transmission to replace a seal.
Don't use those quick stop leak products. They just swell up the rubber which means the seal won't last.

 

[wheelman]

if you are sure its not the pan leaking. try some lubeguard. stuff is pretty darn good

 

[HerrStig]

It worked great until I fixed it....that has happened to me more than once.

 

[Eddie]

As I mature, I begain to see the wisdom in the words, "If it works, don't fix it"

 

[DesertDually]

Originally Posted By: oilboy123
Auto-RX is worth a shot. Not a sales guy for it, but it's done some wonderful things for my taurus. For about $25 for a bottle it beats pulling a transmission to replace a seal.
Don't use those quick stop leak products. They just swell up the rubber which means the seal won't last.


Ok, thanks for the suggestion, good to know. I'm really hoping to find a product I can buy locally, off the shelf in a local store, without having to mail order it. Just my quest for instant gratification and all that.


Originally Posted By: wheelman
if you are sure its not the pan leaking. try some lubeguard. stuff is pretty darn good


I am certain it is not the pan leaking, but thanks for considering it. Where would I find this lubegard stuff and what exactly does it do?

 

[yonyon]

Are you sure you didn't overfill the trans? Is there any possibility you created a leak at the filter allowing air to get sucked in? Aerated fluid would raise the level while driving and also could increase temperatures.

 

[mechtech2]

I hate when this stuff happens.
when working on cars for other people, it is even worse.
But what to do?
Can you check it yourself? Dry things off underneath and see where the leak emanates from? Baby power or flour dusting when dry, they running it can help locate the origin.

If it IS the gasket - good. Have the guy fix it who put it in -for free.

 

[Rand]

Usually you have to retorque the pan bolts several times with a torque wrench or you will get leaks..

this is what my bets are on. might also need a new pan gasket..
or if you replaced it the new one might be cheap?

I know on fords they sell the metal sandwiched rubber type and a cheapo all rubber one that never lays flat.