Rear Diff Cver Leak

[benderzz]

I have a 2002 Explorer XLS with a rear diff leak at the cover seal. Garage i have gone to in the past told me they need to take the entire rear end apart to replace this gasket (estimate $500) i cannot believe this is the case (although i have trusted this shop)

Is thius the only way to replace this seal/gasket on the cover?

 

[Merc02]

I don't think it should cost that much. I think its just some sealant from a tube, and a refill. Try another shop.

Maybe they want to do the drive-shaft input seal, and the two seals on the sides at the same time. That would cost more, but $500 more?

 

[imp]

Those covers do not start leaking very often. If there is oil drops along the bottom side of the differential case, look very closely at the driveshaft (front) end, to see if oil is leaking past the pinion seal, and getting blown back to the rear of the case, making it look like a cover-plate leak.

Pinion seal replacement can be tricky, because the pinion bearings are necessarily pre-loaded, and removal of the companion (U-Joint) flange disturbs that pre-load. A nice, quiet-running gearset depends on absolute rigidity of the pinion gear support, hence the pre-load. imp

 

[matt0248]

ITs been awhile since i've been under the ol X but, I am not certain that the rear cover can be removed with dropping the diff. I remember it is a very tight fit to the top bolts.

 

[jrford]

'02 i hear a lot are leaking from the side seals too, it was a two piece design which was superseded by a newer better once piece seal. If i remember there is a rear cross memeber that holds up the diff thats bolted to the rear cover. . .it has to be pulled to get the cover off (not 100%), which probably means the half shafts have to come out too. Word of caution sometimes leaking seal might indicate the bearings maybe going too. . .

How much is leaking?. . my old heep leaks about a dime sized spot worth over night for 8 years now, i just check it every oil change it dosn't seem to lose much. Last time it went over a year, i think i added a half pint. But since the heep has 170k on the clock and is 16 years old thats all i'm going to do . . .

 

[ericautopart]

Bwahaha 500?? Crooks. If it's leaking out of the diff COVER it's an easy DIY job that should take no longer than an hour. The only time consuming part will be draining the fluid and re filling it. I've seen factory 02+ IRS diffs come in with RTV on them and sometimes cover gaskets. Remove RTV, clean the surface area, and replace RTV. Done. Ofcourse check the cover and such for damage that would cause the leak but I don't see how it could be damaged.

 

[benderzz]

Those covers do not start leaking very often. If there is oil drops along the bottom side of the differential case, look very closely at the driveshaft (front) end, to see if oil is leaking past the pinion seal, and getting blown back to the rear of the case, making it look like a cover-plate leak.

Pinion seal replacement can be tricky, because the pinion bearings are necessarily pre-loaded, and removal of the companion (U-Joint) flange disturbs that pre-load. A nice, quiet-running gearset depends on absolute rigidity of the pinion gear support, hence the pre-load. imp

 

[benderzz]

Pinion seals are fine..it's the cover seal for sure - rear bearings have both been done within the past three years too, buddy and I did rear/pass. last fall

I have gotten same conflicting solutions on this site as elsewhere 1st) As Ericautopart lovingly claims it's..easy job, unbolt cover, replace seal and re-fill (what one would think)

2nd) Is that there is some rear end disassembly to do to get that cover off, which after further inspection seems to be the case, you/I can't get to those top bolts with out taking **** apart

Don't believe this is an 1 hr. do it yourselfer fix

I am likely going to stick with what I have been doing aka JRFord plan (check & re-fill often) since I too am only losing dime size spot overnight & with 130K on this rig does not seem worthwhile to dump money into it. Little concerned when I tow my boat is all

 

[JoshMcMadMac]

Check to see if you have a LSD...you need the friction additive for the rearend if you do!

 

[benderzz]

Josh - I have not had LSD since college Hahaha, yeh that additive works wonders, I found out about that 2 years ago & it, along with heavier weight lube oil, eliminated chatter I had in the rear end, but now I have this leak. Wonder if the change created problems.

 

[jasongt06]

If you can get a wrench or socket on the cover bolts then you can do it yourself. Forget a new gasket, just run a bead of silicone around the cover and it should never leak again.

 

[imp]

If you can get a wrench or socket on the cover bolts then you can do it yourself. Forget a new gasket, just run a bead of silicone around the cover and it should never leak again.

Mucho agreement! imp

 

[merc04]

I have an '04 Mountaineer, and I too had a leaking rear diff that I repaired in June. It is definitely possible to DIY, BUT.......its a lot of work. I'll attempt to explain. I had to remove the spare tire and hoist, and the three rear diff bolts, then push the diff forward slightly (toward engine), slightly compressing the drive shaft (its a two piece shaft) to allow access to the upper cover bolts. When doing this, keep an eye on the wheel half-shaft boot covers so they don't get damaged. The top bolts are still a B@#$% to remove, but I was able to get them out and remove the cover. My "04 didn't have a gasket, only RTV. I scraped off the old RTV and applied new silicone and refilled with 75W-140 synthetic gear lube,and no leaks (so far).