Transmission Leak

[92saturnsl2]

While driving home from Colorado, a bad transmission leak has started, leaving me stranded until the morning when I can get it into the shop. It leaks when the engine is running, doesn't seem to matter if the truck is in gear or not.

It looks like it's coming out near the bellhousing where the transmission meets the engine, but it's hard to tell because of the severity of it-- The whole underside of the truck is coated and dripping (doing 75 on the highway spread it EVERYWHERE).

Once I noticed it, I started adding fluid, two quarts at a time in order to get me to civilization where there was any hope of finding a shop. Four quarts of fluid got me about 30 miles and by the time I found a motel, it was leaving a trail of fluid everywhere I went and doubling as a mosquito fogger as the fluid burned off the exhaust.

What can cause such a large leak so suddenly? The transmission and torque converter are working fine aside from the fluid pouring out. Is there any possibility of a serious (costly) failure of something inside the transmission? Drain plug is fine, pan seal looks okay.

Any info / suggestions are appreciated!

 

[Steve S]

Doesn't sound cheap , but you have to exactly see where the oil comes from.

 

[sciphi]

Cooler hose letting loose? Fluid does come out very quickly out of the transmission cooler hoses.

Look for a leak at any crimped metal-rubber fittings.

 

[fsskier]

Agreed, look carefully at the cooler lines and connections. I have have never seen bad seals lose oil this fast, cooler lines can pump it our very fast.

Anyone else??

 

[SrDriver]

Same thing happened to me a few years back. It was the line going to the radiator - cooler line.

It was a metal line. Cut it with a small metal tubing cutter. Got some hose at auto parts - a couple of clamps - some fluid and ran the vehicle for many miles after that.

 

[92saturnsl2]

It was raining cats and dogs all through Kansas so climbing under the truck to take a look was near impossible. The oil doesn't appear at the front of the truck, so it's not the cooler lines at the radiator-- Could be where they attach to the transmission, but I can't see up over the crossmember without a lift.

There's transmission fluid covering the engine oil pan which is in front of the transmission-- So I think there's a good chance it's something other than the transmission itself. I've got my fingers crossed!

Ugh.. Stupid vehicles always find a way to break in the worst place at the worst time. I was just bragging to my buddy yesterday how I've never had to take it in the shop!

 

[sciphi]

Grab a few rolls of shop towels and some nitrile gloves (about $8-10 at China-Mart), wipe away the leaked ATF, and feel the lines for a leak. Or grab some cardboard/newspaper, put it under the truck, and watch where the drips are when you turn it on for 10-15 seconds. If it's a cooler line, you'll know it after 15 seconds when more ATF sprays all around.

At least you won't worry about rustproofing this winter!

 

[Jim Allen]

If it's coming from inside the bellhousing, could be a torque converter/front pump seal. If so, it means dropping the transmission. Not much in the way of parts... mostly labor. Good luck whichever way it goes.

 

[crazyoildude]

do not let the transmission run dry for even a full minute that will be pretty much the end

 

[92saturnsl2]

Originally Posted By: crazyoildude
do not let the transmission run dry for even a full minute that will be pretty much the end


It may have been 3-4 quarts low at one point, but it holds 11. Once I saw how bad the leak was, I drove on the freeway with overdrive off so that the transmission was 1:1 ratio with the torque converter locked and kept the fluid level maintained (as best as I could).

The transmission and torque converter worked fine until I parked it. It'll get towed in the morning.

I looked again this evening and I can spot the ATF cooler hoses running above the crossmember in the same area as the bell-housing. So it's difficult to tell if it's the front seal or perhaps a fitting or hose leak.

There's probably not enough fluid in there for me to risk turning it on to spot the leak.

 

[Gary Allan]

There's also pressure test ports that could be at fault here. The cooler lines would be the preferred failure point.

Good luck!

 

[92saturnsl2]

Turns out it was a front pump failure which resulted in the front seal going bad. Strange how the only symptom was a slow leak that got worse over 300 miles or so.

The local shop didn't want to touch it and had me tow it to the Nissan dealer who quoted me $3,000 for a new front pump assembly and seal. If other things were damaged once he was in there, it would be $3500 for a new transmission.

Needless to say I had to leave it there and rent a car to get back home. Probably going to try to sell it out there and get as much as I can out of it. I don't want a $3500 repair bill, or the headache of getting back to Kansas..

 

[Cutehumor]

what was the maintenance history on your transmission?

 

[92saturnsl2]

Originally Posted By: Cutehumor
what was the maintenance history on your transmission?


Owners manual suggests no maintenance for the A/T for the life of the vehicle, only fluid checks.

I owned the vehicle since about 50k. Switched to Mobil 1 ATF at 60k, and drained and refilled again at 120k.