Diff fluid leak

[Dmucci]

I have an 02 with 51,000 miles the only mod is a 456 gear installed at 30,000 miles.

recently I thought I smelled diff fluid during a drive, took the car home and checked underneath-just knelt down to check for fliud on the floor, nothing on floor. Came out the next morning and there were spots of fluid on the floor erraticly spaced between the rear tires - maybe a total of a cup or so. There was no issue with the cars performance and no unusally noises (I did replace the exhaust cat back with straight pipes...better sound) but I have not driven it since I smelled diff fluid - lots of out of town with work - at this time of year I typically dont use it other than a short run a couple times a month to get a fix and keep it active. I change the fluids Oil, Diff, and Trans myself but that is the end of my ability. I am hoping that there is a seal or some other inexpensive fix, that is possible...I can get the car up on jack stands and look around but I am hoping for some encouraging possibilities before I jump through the hoops of getting it off the ground and checking it. If the only possibilities are major items then I might be better served by flatbedding to a local shop. Will it be OK if I leave it until spring? I am really bummed, this is the first issue I have had.

[s2kobsessed]

I'd say it's safe to drive, be cautious of the fluid level though... From your description, can't really tell if this is a new problem or how long it's been leaking for. Short drives shouldn't be an issue, but if it's going away for the season, just let it sit until spring and see if anymore fluid drips out.

[Dmucci]

It has been sitting for 3 weeks now and other than a quarter sized drip now and then no new fluid...It seems like it got on the exhaust (smell) and the half shafts and they spun it all over the place and it was dripping off of areas left and right of the diff. No significant amounts since cleaning up the first mess. I really dont want to damage it, it did run fine when I parked it...

[thereur]

You didn't say if you topped it back up. Since the diff holds under a quart, I wouldn't drive being down a cup. Also, you don't know if more was lost while driving. I would get under it right away. You need to see where it's leaking from.

[desmo4]

If you think a cup leaked out, that is more than half the fluid the diff holds. You should fill it and check it at least weekly until the leak is repaired. Your gear installer probably missed a spot of sealer when he assembled it I would bring this issue to him.

Jonathan

[thereur]

at least weekly until the leak is repaired.

Really??? But he doesn't know if it's leaking more while driving. Until he confirms the rate of loss with several level checks, I wouldn't do any normal driving.

[Dmucci]

No way to avoid crawling under it...I will refill it, your right that is the only way to really know what was lost and maybe the leak will be obvious. The new gear install was so long ago almost 3 years, that wasnt what came to mind. Since it was my son who did the job at least I can follow up easily. He was at a mechanics tech school Wyotech- and his instructor was an ex Honda tech - they did the new gear install as my sons differential competency (free labor) and many eyes following the job, most of the instructors were very interested in the car and many participated in the work. I was concerned but after proper break in and all the years and miles...I know, I know time to get dirty...more info to come
Thanks for the responses

[thereur]

There's a couple washers there - drain and fill. You can normally reuse them a number of times, but it might be good to have replacements handy before you go under there. Good luck.

[lonestarbuzz]

mine did this same thing not too long ago. turns out i overtightened the drain bolt and it warped the gasket. changed the fluid again and tightened to just under spec and it has been fine since.

[repiv]

All good advice so far. Let me add ..............................

A cup of fluid is a lot for this diff as it only holds less than 0.8 qt. First thing is to top it up with the proper fluid (GL-5) and keep an absorbent mat under it so you can monitor the loss. If you don't drive it to the extent that would heat it up too much, then it should be OK to be down a slight bit. Keep the drives short and don't put too much load on it. You really should get to the heart of the matter and fix it.

Fluid can leak out of the diff in the following places. You need to investigate and find out from where.
1. You say it's coming from the left and right output shafts. There is a seal that each shaft runs through. It is very easy to nick that seal during the gear swap. Those seals needed to be cleaned and then a heavy layer of grease applied to them while the rest of the work was being done. If debris got onto the seals then the output shafts would eventually rub that material in and damage the seals. This could take weeks, months or even years. Replacing those seals can be done with the diff on the car but it's still quite a bit of work.
2. The back, finned casing of the diff came off. The old sealant needed to be completely scraped off. If it wasn't, leaks can occur. Also, a good bead of new sealant needed to be applied with NO breaks and going "inboard" of each bolt hole. If it's leaking from this mating surface, the diff has to come out.
3. The front prop-shaft output flange seal could also have been damaged in the same way as the left and right output shaft seals. Again, this can be done with the diff on the car, but still some work to do.
4. The drain bolt may be leaking. A new crush washer will fix this.
5. The fill bolt may be leaking but since it's high up, this is rare but again, a new copper washer will fix this.
6. A severe overfill can push fluid out the breather hole. If this was the case, then you should see a stabilization of the fluid loss. This is very rare as it's extremely difficult to overfill that much unless the car was tilted over to the passenger about 45 degrees.

PS. Make sure it's diff fluid. We have fluid filled diff mounts that have been know to fail and leak a reddish brown fluid. Also, diff fluid stinks of sulfur. The fluid from the mounts shouldn't smell that pungent.

[SpitfireS]

A severe overfill can push fluid out the breather hole. If this was the case, then you should see a stabilization of the fluid loss. This is very rare as it's extremely difficult to overfill that much unless the car was tilted over to the passenger about 45 degrees.

Maybe the installer filled it while it was off he car.
Much easier to fill.
Easier to overfill too.

PS. Make sure it's diff fluid. We have fluid filled diff mounts that have been know to fail and leak a reddish brown fluid. Also, diff fluid sticks of sulfur. The fluid from the mounts shouldn't smell that pungent.
Hmm .. there seems to be no "I agree" smiley.
That is what I would post here.

:yo:

[thereur]

Hmm .. there seems to be no "I agree" smiley.
That is what I would post here.

:yo:

Definitely. :thumbup:

[desmo4]

[QUOTE=thereur;535071]Really??? But he doesn't know if it's leaking more while driving. Until he confirms the rate of loss with several level checks, I wouldn't do any normal driving.[/QUOTE

If you read the original post he estimated he lost about a cup. And that is a serious amount.

Jonathan