axle seal and leak help

I am leaking gear oil out of the passengers side axle. Now I was hoping just the seal needed to be replaced. A shop looked at it and said the axle house appeared to be bent so just replacing the seal would not help. I brought it home to check it out myself. Now this is a Used axle I bought because of the gear ratio so I really don't know its history. I checked the tube on that side with a straight edge in as many places as I could (not a bracket in the way) and it appears to be straight.
I talked to the shop again and was told "you can't tell from the outside, you have to tear it apart and check from the inside" I'm not sure I understand why.

This is a Dana 30 front BTW

Now I might buy that it is bent because here is what happens.
If I park it with the wheels turned to the left it leaks a lot, I can stand there and watch it drip out. The first night I did this I lost about 1/2 quart, made a nasty mess.
If I park with the wheels straight ahead it leaks about a 3 inch circle over night.
If I park with the wheels turn to the right I get a couple drops.

Now I can see the short term solution here, but I don't want to pay for a new seal to be installed if I'm just going to have to junk this axle.

Any opinions are welcome.

Is it the housing or the axle shaft that is bent?

A bent axle shaft will eat up a seal fast. If the housing is bent I would think that you would have some driveability issues, pulling hard or wearing tires fast.

To fix the seal the axles have to be removed and the ring gear and carrier have to come out. No set up will be required since the D-30 uses shims between the races and carrier. Basically just pull the carrier out carefully and replace the seals and then reinstall the carrier and tighten to spec., then reinstall the axle shafts. Don't be surprised if it takes some force to remove that carrier, I use a comealong and a strap to pull them.

Well I don't know if either is bent for sure, the shop claims that the housing is bent, but it drives fine and they say the alignment is fine.

The fronts are semi floating, meaning the axle shaft centers at the outside axle U joint and the ring gear. A slightly bent housing, shouldn't mess with the seal much. A bad u-joint, will cause wobble, which can eventually help the seal to fail.
I've had a seal weep a bit and then dry up after a U-joint change. I've also packed the housing with sand and had the seal get eaten up pretty quick.
I've also had a plugged vent, that forced oil past the seal when hot. Blow through the vent hose and see if it's plugged. Hard to plug up the front diff vent hose, but anything is possible, I covered my outlet with mud.
If you can't see the bend with a straight edge, it likely isn't enough to make much difference IMO. The front end tolerances just aren't that exact, XJ's are famous for plus or minus 1/2 inch differences in wheel base and other fit.
A bent axle shaft is a possiblity, but unlikely.

Sounds to me like the shop just don't want to mess with. The front seals are inside near the center and the cost of labor would be high.

There is a aftermarket seal kit the goes on the out side someone can post a link to.
Make sure the fluid level is not over full also, most front axles will leak out the extra oil.
If you been in deep water the water will also force the oil out.

The interesting thing about it being over filled is it was. It was at this shop for some other work and they changed the gear oil, well he said he put 3 quarts in it which seemed high, since I couldn't ever even get 2 in there. Well after the first leak I pulled the fill plug and quit a bit came out before it was level so there is no doubt he overfilled it.

I was just wondering how the steering would affect this leak.

Well because of the wheel camber the wheels and axle lean right and left when turned. Like \ and \ or / and /.

The correct Laval should be just below the filler plug, better check the rear also before it leaks out on your brakes.

I don't think your axles bent, the shop may be a little crooked though.

langer1 said:

There is a aftermarket seal kit the goes on the out side someone can post a link to.

Click to expand...

http://www.quadratec.com/products/52420_900.htm



These are seals but not in the same sense as the inner seals are. They only provide protection from outside contaminents (to some extent). The more grease you apply, the more that fills the axle.

I've used them now for two years. What's the benefit? I don't know other than the apparent confidence that crud won't get into the axle. How sure am I of that? I'm not, never removed them to inspect the innards. Would I recommend them? Yes, but only with perceived confidence.

I think that as grease builds up in the axle behind the seal, it actually may prevent diff oil from leaking out and probably would hide a leaking inner seal.

Now keep in mind that I probably grease mine far more often than most. These seals are designed to be greased often for longevity and performance. Neglect will more than likely cause the seals to rapidly fail (there are two seals about 1/2" apart) and when that happens they will no longer do their job.