Pumpin Pressure?

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Changing the front and rear diff lube. Front had a bit of pressure release when I removed the fill plug and the rear had even more pressure. Is this normal? Also for some time I've had some type of seeping leak on the rh rear axel area. Thought It might be brake fluid because there's a tee there but after getting back from the PMC Swap Meet (440 miles round trip), I now find quite a bit of gear oil drippage there and even back on the spare. I believe it's gear oil this time. It smells like sulfer.
These bad pics might help.

Russ in California :cool:
 
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the rear axle brake tee has the rear axle breather integrated into it. Whenever there is a pressure difference inside an axle it means your breathers are clogged. This can blow out rear wheel seals of knuckle inner axle seals, and lead to accelerated knuckle weeping or rear gear oil leaks. Read the writeup in tech and replace your factory one-way valve with a brass nipple fitting and run a hose to a higher location.
 

lovetoski

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Extended breathers are an easy mod. Do it to both axles. It'll help if you ever go into water deeper than your axles, but more importantly it'll do a better job than the OEM breathers, which means your axle seals will last longer.
 

lovetoski

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Russ in California said:
Where's a good place to relocate the rear vent to? Not much back there higher than the top of the fuel tank.
Thanks,
:cool:
Run it along the PS frame rail, connect it with a T to the front breather, and up into the engine compartment. 15 ft of tubing, 1 T, one VW fuel filter, a few hose clamps, and a few zip ties. 45 minutes max.
 

Cruiserdrew

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Russ-Run it forward through the frame rail, and then up to the firewall. I used a d-clamp and bolted the top of the breather tube to the very top of the firewall just under the hood. Then cap with a generic fuel filter and you're done. It's a 10 minute mod, and should last the life of the truck.
 
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The engine compartment does seem like the logical choice. I just thought it a long way to pipe the vent though there's no place high enough in the back.
Do I need to worry about replacing the whole assy from where the tube plugs into the diff OR can I just splice and extend the hose that's there?
:cool:
 

Cruiserdrew

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Russ in California said:
The engine compartment does seem like the logical choice. I just thought it a long way to pipe the vent though there's no place high enough in the back.
Do I need to worry about replacing the whole assy from where the tube plugs into the diff OR can I just splice and extend the hose that's there?
:cool:
The FJ60s have a nipple on the axle assembly-just pull off the old hose and start with a new one. I used 1/4 fuel line-the low pressure stuff ($1 per foot) not the high pressure fuel injection stuff ($3 per foot).

I have heard of people running the line up into the rear quarter but I think that would make the inside smell like gear oil.
 

Pluton

 
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Wtih long horizontal runs on a gear oil vent, over many heating/cooling cycles, couldn't the gear oil vapor condense in large enough quantities to restrict or clog a hose that doesn't have gravity draining the goo back into the diff? Or do they just clog anyway? Seems like colder climates might aggravate the [potential]problem. Just a thought.
 
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