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Rear differential leak...

XJeffro

NAXJA Forum User
Location
Indiana, PA
I noticed something leaking out of my rear differential the other day. i was wondering if this is of concern, if it easliy fixed, and what might be involved to fix it.
i am assuming that the seal is worn. should i just pull off the seal and refill with lubricant? also, what lubricant should i use? thanks for the help in advance.

fa1c7656.jpg
 
Matthew Currie said:
That seepage is pretty common with the rubber plug. I wouldn't worry about it. You might want to check the level, but I bet it isn't measurably down.

Your plug probably hardened with age and it just doesn't seal too well.... new plugs are about $5 from the dealer :D

Fluid... you most likely have 75/90 gear oil, unless you tow and then use the 75/140 (synth)....
 
Kejtar said:
Your plug probably hardened with age and it just doesn't seal too well.... new plugs are about $5 from the dealer :D

Fluid... you most likely have 75/90 gear oil, unless you tow and then use the 75/140 (synth)....

Also if you do decide to change the oil, if you have the limited slip, you have to add the friction modifier....
 
ok, i'm glad to hear it isnt a huge problem.:)

what is the best way to replace the plug and the fluid, . if someone could give me a quick rundown of this process i'd appreciate it.
 
the plug is easy to replace... just insert a 3/8" socket wrench and remove it. Then simply put the new one in. There should be any fluid leaking out when you remove the plug because it shouldn't be filled that high.
 
FatXJ said:
the plug is easy to replace... just insert a 3/8" socket wrench and remove it. Then simply put the new one in. There should be any fluid leaking out when you remove the plug because it shouldn't be filled that high.

Fat :D you haven't looked at the picture close enough.... it's one of them rubber ones :D.

To pull it out... just pry it off..... if the fluid has not been changed forever, just take the bolts off, pry the cover off (probably stuck with RTV), clean old RTV of the cover and then apply fresh RTV and put it back on. Let it set a bit then tighten (don't remember the torque specs of the top of my head) and then fill it up with oil... and then put the plug back in.
 
Just did my rear diff, on the weekend.
Torque spec on the bolts are 28-33 Ft lbs. Remember to criss cross when tightening the bolts.
Depending on weather temp. let the RTV sit for an hour before refilling. Fill just till you start to see the oil coming out of the hole.

If the plug is real hard and old, drop by the stealership and pick one up.

Check out Stu's site for great write up on changing the diff oil.

http://www.stu-offroad.com/misc/diff-1.htm
http://www.cyber-fish.com/fordeec/light_axle_service.pdf
 
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