Front Differential Oil Leak?

AFF

TJ Enthusiast
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Dec 26, 2020
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Texas
OK, I'll start off by saying I'm not very mechanically inclined. I can do just enough to be dangerous.

I have a new oil spot on the driveway that is directly under the front differential. By new I mean within the last week. It's probably about 3 inches wide by 4 inches long (driveway is slightly slanted). I haven't been able to look at it yet. What do you think the issue might be? Expensive repair or no?
 
Well when the weather warms go crawl under and see where its coming from if its where the front driveshaft goes into the diff its the pinion seal.
 
Well when the weather warms go crawl under and see where its coming from if its where the front driveshaft goes into the diff its the pinion seal.
I couldn’t wait for warm weather. I pulled the Jeep into the garage to have a look.
It looks like it is leaking from the seam of the differential where the horizontal rib is in the first picture.
34E1EB38-F2F3-4D23-A815-E5F4A3DF6778.jpeg
There is no oil on the top. It is running down the seam and drips off the bottom. It’s been in the garage for less than an hour and there is already a dime size drop of oil on the cardboard underneath.
3617684F-A365-44D1-A8E5-4F956A1702A5.jpeg

Here is the spot on the driveway with the $5 as size reference
C04B0A90-710F-47A0-8F91-ADBEF717E046.jpeg

The oil is pretty clear, not burnt or anything. I smelled it and it smells like, well... oil. I wouldn’t know what differential oil smells like compared to engine oil.
B8F0C355-5A6D-4F12-B0D2-2B08B7D366C2.jpeg

So, as I stated in my original post, I’m not the most mechanically inclined. What do I need to do to fix this?
 
GAsket replacement
you need a gasket get a Fel Pro you wont need gasket sealer for a fel pro gasket
a scraper to scrape the gasket off the diff cover and the diff housing Putty knife and razor scraper
and a socket think its a 13mm and a ratchet
Diff Oil
Brake cleaner for the diff cover and rags
and a drain pan to catch the diff fluid in when you take the diff cover off

1. put drain pan under diff housing
2. clean the diff cover with brake clean before removal
3. use the 13mm ratchet to remove bolts
4. gently pry cover off with a screw drive. tThis when the diff oil is going to come out in hurry
5. clean all the gasket off of the diff housing be careful not to get any pieces of gasket material in the diff housing a towel stuck aroung the ring gear helps
6. clean the gasket off the diff cover
7. wipe both gasket surfaces clean with brake clean (the diff housing and diff cover)
8. clean the bolts
9. put a couple of bolts through the diff cover and hang the gasket on the bolts
10. get the 2 bolts started in the diff housing
11. get the remaining diff bolts started and all of them finger tight
12. tighten in a crisscross pattern you should use a torq wrench for this do not over tighten
13. remove drain plug from diff cover and fill with correct weight diff oil till it just comes out the fill hole you are putting it into a piece of rubber hose over the pointy end of the filler on the oil bottle makes this a lot easier or an oil pump filler for a lower unit for an outboard boat motor is what i use
15. clean the fill / Drain plug and reinstall
16 this is a good time to inspect the for metal shavings the fill is a magnet and will collect the metal shavings there
 
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Yes, it’s water. The ice is melting off the Jeep.

Do the gaskets come in shapes/sizes?
 
Yes you need one for a dana 30 unless you have rubicon or LJ as they both have dana 44
use Vin# and year make and model = Wrangler Sport, unlimited=LJ, X
 
Side Note- personally I would take that aftermarket cover off and put a stock dana cover back on. The factory covers are designed to direct oil in certain directions inside the diff for lubrication and cooling Check out Gale Banks diff cover video on youtube.
 
I appreciate all the help. Sorry for the multiple questions. It is a rubicon. I’m on the far north side of SA (outside 1604, about half way between 281 & 35).

Royal Purple syncromax is transmission fluid. Should I get the 75W-90 gear oil Instead?

I’ll probably end up doing the rear diff, also. It also has the Rockcrusher diff cover. Why would someone change them if they are not oem?
 
Royal Purple syncromax is transmission fluid. Should I get the 75W-90 gear oil Instead?
Your axles require a gear lube that has a GL-5 rating. The exact viscosity is not important, a 70W-80, 75W-90, 85W-120, etc. is fine. Personally I prefer a conventional gear lube inside our axles (gears run cooler with a conventional gear lube) but for an existing axle a synthetic GL-5 is fine too.
 
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My bad on the Rp Synco I Meant Synthetic I am over here by Smithson Valley HS, if you get in bind and need help call me 210-563-6051 Shaun its gonna have to thaw out first