Transmission Fluid Drip

Wondering how long it usually takes for the front seal to let loose once it starts dripping and if anyone has good results with the seal softeners?

Little more info: 1996 Chevy 1/5 ton with 5.7 liter motor and 145K miles. We just started noticing a drip on the driveway. I looked today and no new drip so maybe a drop every other day or so. Fluid level is still full. Debating the stop leak stuff but wondering if it does more harm than good. If the seal goes, I expect I'd be better off changing the entire tranny anyway as I haven't heard of too many of these running this long.

Thanks for any advice and shared experiences. bobby bbusselman at hotmail dot com

Reply to
bob
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Oh yeah,

I have changed fluid and filter twice so far, at ~50K and 100K miles. About time to do that again but may hold off

Reply to
bob

I don't think you are going to suffer total failure on a front pump seal. Are you sure the front seal is leaking? If it is, remember that it rides on the torque converter snout, which can develop a wear groove on it that will compound leakage on a replacement seal.

I wouldn't recommend seal sweller additives; not from personal experience but from the standpoint that for them to be effective, they must basically destroy the rubber in your seals/Orings.

Toyota MDT in MO

Reply to
Comboverfish

That seal might drip a bit, even intermittently, for a good long while without rapidly deteriorating. Depends.

Your tranny has enough miles on it, it is no longer a virgin. If you plan to trade the truck soon, you might want to nurse it along because you wont get much money back from such a repair.

The old transmission seal additives were solvent based, and softened the elastomeric seals. They worked sometimes, but not to the long life of the seal.

The newer materials are polymers which do not soften the seals, but sort of collect at the leak and decrease the seepage. The jury is still out on them, but if you use a good brand name, it could work for you.

Reply to
<HLS

Thanks for the replies. Basically wondering how long they usually last once they start to drip. I believe it is the front seal as the fluid is dripping from the bell housing. I've only had one fail to date and I didn't notice it was leaking until I followed the fluid trail up to the parking spot. I really didn't think the seal softeners would be a good idea because I thought they would increase seal wear as you guys say but was looking for opinions.

Will do some research on the polymer stuff mentioned by HLS though

Reply to
bob

Don't know about your specific vehicle, but my 1994 Dodge Caravan w/

3.3l & OD developed a very slight leak at the front seal. It did that for a couple of days, then started pissing out. Shop informed me it was a bearing in the pump that went, and took out the torque converter as well. Good thing it was under warranty...
Reply to
Raymond J. Henry

If the actual bushing that carries the load of the torque convertor is still fine and its just the rubber seal leaking a bit, the thing could last 200,000 miles that way. Or the seal might tear in a week- its hard to predict- but that ususally only happens if the bushing is bad allowing the torque convertor to wobble around more than it should, chewing on the seal.

Just because its coming from the bellhousing doesn't mean that it's the front shaft seal, though. There are several other things that can leak in there. There's the front pump-to-transmission case seal, the torque convertor itself (they sometimes develop hairline cracks, or leak at pinholes in a weld that was missed during manufacture/testing), and the transmission atmospheric vent.

If it were mine, I'd keep an eye on it and if it doesn't get worse over the course of a few weeks/months, just live with it.

Reply to
Steve

Don't know about "how long". I think there are too many variables involved. I once had an '73 LTD that developed a minor front seal leak. Went away by itself. Had an '82 Corona that also had the leak. Cost to repair was more than the car was worth. Tried a bottle of some brand of sealer fixer and it actually worked for the couple more years I had the car. FWIW YMMV DFB

Reply to
NickySantoro

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