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Rear main seal

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Old Jul 18, 2021 | 05:55 PM
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Rear main seal

If the rear main seal has given way, wouldn't you be able to smell gear oil? I just noticed that either I ran over something wet which I don't think happened or I've got liquid from Where the rear axle and diff meet up. But it looks like it was spun off of it and I can see it all over the leaves and just about everything else in that area.
 
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Old Jul 18, 2021 | 06:00 PM
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Rear main seal is on the engine. What your referring to is the pinion seal. Yes they can occasionally leak, more so common on the Sterling axles.
 
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Old Jul 18, 2021 | 06:05 PM
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Just got back from a camping trip and was inspecting, diesel water release etc and found it but it doesn't smell like gear oil




 
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Old Jul 18, 2021 | 06:10 PM
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That's odd though. I wouldn't think I would have any on the spare tire.
 
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Old Jul 18, 2021 | 06:13 PM
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Pinion seal for sure.
 
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Old Jul 18, 2021 | 06:18 PM
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Originally Posted by ford390gashog
Rear main seal is on the engine. What your referring to is the pinion seal. Yes they can occasionally leak, more so common on the Sterling axles.
Ah ok, is sterling what I have? Should I be able to smell gear oil? Looks like I'll get to test out the warranty.

When you say occasionally? Is that to be expected and it just happens hear and there with no concern?

Thanks!
 
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Old Jul 18, 2021 | 06:29 PM
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Originally Posted by Matt Pace
Ah ok, is sterling what I have? Should I be able to smell gear oil? Looks like I'll get to test out the warranty.

When you say occasionally? Is that to be expected and it just happens hear and there with no concern?

Thanks!
Hopefully you have a extended warranty, this isn't covered in the 5/100k Diesel warranty. Yes that is a Sterling axle pictured.
 
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Old Jul 18, 2021 | 06:30 PM
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Did I miss what year, make and model of vehicle this is?
 
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Old Jul 18, 2021 | 06:31 PM
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I wouldn't worry about smelling it or not. That looks like an obvious pinion seal leak. Not sure it is common, my Sterling has 190k on it and no leaks, but it happens.
 
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Old Jul 18, 2021 | 06:37 PM
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check your vent on the axle tube if blocked it can cause a leak
 
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Old Jul 18, 2021 | 06:39 PM
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Got it and thank you. I did take the fill screw out and fluid came rushing out so definitely has a lot of fluid in the diff. I would expect it to be low since it's spinning fluid but its really full.

2017 6.7

I know the previous owner had diff service so maybe they put too much it at an angle?
 
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Old Jul 18, 2021 | 06:46 PM
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Originally Posted by 4wd6.7L
Did I miss what year, make and model of vehicle this is?
From what I remember the truck is a 2017 6.7 F250 the OP bought used with 8*k.
 
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Old Jul 18, 2021 | 06:47 PM
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Originally Posted by Matt Pace
Got it and thank you. I did take the fill screw out and fluid came rushing out so definitely has a lot of fluid in the diff. I would expect it to be low since it's spinning fluid but its really full.

2017 6.7

I know the previous owner had diff service so maybe they put too much it at an angle?
It's just a small leak currently, it will get worse if not fixed.
 
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Old Jul 18, 2021 | 06:57 PM
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Ok, calling to try out the aftermarket warranty that I fought the sales guy on. I'm sure I'll end up paying for it even though I'm paying for the warranty.

Well I knew buying used would present some issues early on but didn't think it would y this early
 
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Old Jul 18, 2021 | 07:17 PM
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Originally Posted by sweeperman
check your vent on the axle tube if blocked it can cause a leak

If it was full of fluid like mine is, this might be something to investigate? Would unblocking it be the fix or the blockage caused the seal to break and still has to be replaced?

Thanks y'all for the help!
 
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