bwFX42006

I just noticed some rear diff fluid leaking around the end of my axle housing tube....I can assume it's been leaking for several weeks....but my question is....could there possibly be any long term damage? I have no clue how long its been leaking and just recently noticed....the truck hasn't been running any different and there has been no rear end chatter....I just can't help but be concerned.

lewissa81

Worst case scenario is the rear diff loosing too much fluid, toasting everything in there. Keep an eye on the fluid level and replace the seal. It's best to replace both seals at the same time. If it's been a while, I suggest replacing the wheel bearings also, since you'll be in there already.

bwFX42006

Just checked and it seems that my axle vent tube is cracked right where it attaches to the tube. I'm guessing that it caused the seal to blow out due to an increase in pressure inside the differential housing. Gonna replace the seal tonight. Any suggestions on oil? I had an old timer tell me all he uses is regular 80-90...not sure if thats the way to go or not.

lewissa81

Check your manual for the fluid and check your axle id to see if you have a limited slip. If you do, you'll need friction modifer.
I think most rake 75w140. I could be wrong, but that's what mine takes.

lewissa81

Just saw the fx42006 in your name, so you will need friction modifer and 75w140. Do both seals now to save you time money. You have to drain the diff, and that fluid is expensive! You'll need 3 quarts, a 4oz bottle of Ford friction modifier, and some black rtv.

bwFX42006

was thinking about just buying royal purple with the friction modifier already added

tomb1269

You need to use the recommended weight in synthetic and you need to add friction modifier. Search for write ups and utube videos. The vent tube would not have cause a seal to fail as the pressure would have moved back to the center section and vented there. Now if you have a cracked vent tube then you could have introduced water and junk in that damaged it, which is more likely.

gone postal

plan on replacing the parking brake shoes while you're in there.

Especial86

iTrader: (1)

Use repair bearings.. Don't even chance using standard wet sump bearings.. This side faces out.. They convert you bearings to grease, and are double sealed to keep the fluid out.. No more leaks, and a guaranteed good fit if your axle tube has signs of wear.. New O ring seal, plus new inner seal to keep fluid out.. Part number is listed on the box on the wall.. They are around $46 each.. Pin removed with axles: Don't rotate the carrier while the pin is out, or else you will be reinstalling the spider gears and there shims when they fall out.. Not a big deal since I made this mistake, but you don't want to mix up the shims.. I'd help you out more but I just had a hell of a time making this post with the busted iPhone app..




Part# RP 1561 FO

VTX1800N1

I haven't seen those before. Are the wheel end bearings a problem? I haven't heard of many of these going out. Usually it's the carrier or pinion bearings.