Ford 9" rear end leaking at Axle Seal

95yjjeep

Well-Known Member
Joined
Jun 7, 2006
Location
Charlotte
Hey guys. I’m need some help, please! I just swapped brakes and bearings on my Ford 9” housing from a mid-80s Ford Truck (it’s in my Mail Jeep). One side leaked with the old setup (and I swapped bearings and seals twice within 1000mi trying to fix it) and I assumed the spacer setup I was running from Currie Enterprises was the issue. Well, I completely swapped brakes and put new bearings and seals in without any spacers using some Ruffstuff weld on caliper brackets and K10 calipers. The same side is still leaking pretty badly.

I setup the rear end with new bearings, seals and lock rings. I used the factory Drum brake center that I cut out to make it fit with the proper axle flange backspacing so the bearing sat in the axle housing properly. Basically, the axle is setup with the exact same specifications as factory now and that one side is still leaking like crazy. Any ideas? Could it be a bent axle shaft? Or the welded on axle flange itself? What should I do?

What I do know.
1. I'm running the right amount of gear oil. 2.5-3qts. (knowing too much oil isn't forcing it's way out)
2. It's the same side that has always leaked.
3. With the jeep running and standing behind it or when I was grinding on the shaft mounting surface, there didn't seem to be any wobble in the shaft to make me think the shaft was bent.
4. This is the 3rd set of bearings, seals and bearing races I have installed to alleviate this problem. The final time is with a completely different brake setup too to eliminate the Currie Enterprises bearing spacer ring that they sell to make a Ford Explorer brake setup work for a Ford 9".
5. The Ruffstuff brackets and K10 calipers are a floating caliper setup so I would assume that is not the issue. The Ford Explorer setup was a floating setup also so the axle can move as needed.

Some photos...
This photo shows how I cut out and used the factory drum brake center to sandwich between the axle mounting flange to the axle retainer plate.
ai1024.photobucket.com_albums_y309_95builtjeep_gone_20postal_IMG_0184_zpslhk2vz8g.jpg


Then that piece was cleaned up and placed in between the axle housing and the bolt on 9" axle shaft retainer plate.
ai1024.photobucket.com_albums_y309_95builtjeep_gone_20postal_IMG_0186_zpsiartj2yj.jpg



Final setup.
ai1024.photobucket.com_albums_y309_95builtjeep_gone_20postal_IMG_0206_zps4d1fynuw.jpg
 
Rtv and diy gasket maker both sides of the retainer.
 
Can you tell if it if leaking around the seal to shaft or seal to housing?

It looks like there is gear oil on the center portion of the backside of the axle shaft where it cones outward to the wheel mounting surface. It's also dripping around the mounting flange. It flings oil really badly all over the inside of the tire and onto the brake rotors.
 
best thing is to thoroughly inspect all seal surfaces. Make sure the shaft has no reason not to seal. Pack the seal with grease before you press it on. Check the housing end for anything that would prohibit sealing. Coat the outer edge of the seal with grey rtv before installing it into the housing. Make sure the housing is not bent and it is not causing the shaft to bind against the seal.
 
best thing is to thoroughly inspect all seal surfaces. Make sure the shaft has no reason not to seal. Pack the seal with grease before you press it on. Check the housing end for anything that would prohibit sealing. Coat the outer edge of the seal with grey rtv before installing it into the housing. Make sure the housing is not bent and it is not causing the shaft to bind against the seal.

Thanks so much Lee. That is great input! I'll work on that this weekend and see if it can fix my issue. Thanks for your time!
 
Sounds like a seal surface problem, yeah. When you clean it up, is it still leaking when sitting still? This can tell you if it's a static leak or if it's pumping fluid when rotating. Surface finish problems and conditions that cause the sealing surface to not be concentric with the seal can both cause pumping.
 
Just a side note,;make sure your breather hose is not plugged. If the housing is building up pressure when it heats up the weakest seal will probably puke fluid. An open breather will help keep things from puking.
 
Sounds like a seal surface problem, yeah. When you clean it up, is it still leaking when sitting still? This can tell you if it's a static leak or if it's pumping fluid when rotating. Surface finish problems and conditions that cause the sealing surface to not be concentric with the seal can both cause pumping.
It only leaks when it's been rotating. It pukes while going down the road and then when I stop it keeps dripping for a little while. When it's static in the garage, it doesn't leak much if at all.

Just a side note,;make sure your breather hose is not plugged. If the housing is building up pressure when it heats up the weakest seal will probably puke fluid. An open breather will help keep things from puking.
I'll check this. I'm running one of the closed breather tubes. You think I should run a factory style open hose for a little while to see if that could be a contributor also?
 
I'd definitely open up that breather tube.
 
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