Oil leak on axle cap!

[mick88]

My Perentie is throwing a bit of (differential) oil out from around the plastic cap on the rear axle. The cap is a recent replacement (after market brand). Is there an oil seal further in on the axle that has failed and needs replacing.

Cheers, Mick.

[Bearman]

My Perentie is throwing a bit of (differential) oil out from around the plastic cap on the rear axle. The cap is a recent replacement (after market brand). Is there an oil seal further in on the axle that has failed and needs replacing.

Cheers, Mick.

No inner seal there Mick. Most likely cause is an imperfection on the inside contact area of the aftermarket cap, some of them are pretty ordinary. It also could be a burr etc on the drive flange contact area. I inspect the cap and flange (make sure it is clean and dry) and then put a bit of silicone around the contact ring when I install them. That seems to stop leaks.

[mick88]

Thanks Brian,
Will give it the silicone treatment later today then replace the after market caps with the "real thing" when i get home.


Cheer, Mick.

[BadCo.]

Would another option be to replace the drive flanges with the HD ones with the threaded cap?

[Chris078]

No inner seal there Mick. Most likely cause is an imperfection on the inside contact area of the aftermarket cap, some of them are pretty ordinary. It also could be a burr etc on the drive flange contact area. I inspect the cap and flange (make sure it is clean and dry) and then put a bit of silicone around the contact ring when I install them. That seems to stop leaks.

What silicone would you use for this procedure?
My appear to be installed this way on both front and rear diffs. I'm assuming this means that they leak without the silicone being there.

I can't get the plugs out either. I assume I just need a bigger breaker bar for the job.

[Bearman]

What silicone would you use for this procedure?
My appear to be installed this way on both front and rear diffs. I'm assuming this means that they leak without the silicone being there.

I can't get the plugs out either. I assume I just need a bigger breaker bar for the job.

Silastic, just a small amount on the contact area. Some will leak for no apparent reason, that's why I use it. Are you referring to to the drain/filler plugs? Make sure you use a socket or the corners will end up rounded.

[Chris078]

Silastic, just a small amount on the contact area. Some will leak for no apparent reason, that's why I use it. Are you referring to to the drain/filler plugs? Make sure you use a socket or the corners will end up rounded.

Thanks.
Yes the drain/filler plugs. Interestingly, the front diff both drain and fill plugs are just the 1/2 inch input on a socket wrench.

On the rear, the drain is a 1/2" input and the fill is a 17mm nut.
I swear I needed a different socket size for just about every nut I removed yesterday changing the engine/trans/PTO/gearbox oil

[rathgar]

Thanks.
Yes the drain/filler plugs. Interestingly, the front diff both drain and fill plugs are just the 1/2 inch input on a socket wrench.

On the rear, the drain is a 1/2" input and the fill is a 17mm nut.
I swear I needed a different socket size for just about every nut I removed yesterday changing the engine/trans/PTO/gearbox oil

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