1999 Explorer Differential

[le33sw]

Just bought an Explorer

Year: 1999
Mileage: just over 110,000 miles
Model: 4.0, XL (160hp version, so OHC?)
Location: Vancouver, CA

Yesterday I managed to get it up on a ramp and noticed that the rear differential is not ‘dry’ like the front one. It is not dripping, but just a bit ‘wet’ all round. There are no funny whirring noises that I can decipher. It drives fine with no problems. Is this something I should worry about or should let sleeping dogs lie?

It would also be very helpful if someone can suggest an honest (and not too expensive) garage that I can take my car into – I really don’t want to take it these ‘quick fix’ places, since they ‘manufacture’ problems.

Thanks in advance.

 

[btimm86]

probably just from where someone filled it up and spilled

 

[Blee1099]

I would remove the fill plug and check to see if the fluid is to the level of the fill plug. Actually since you just bought it, I'd really recommend you getting all the fluids changed to be safe. If the rear is a limited slip make sure you use the additive. Their are 2 version of the 4.0, an OHV and a SOHC that was available starting in 1997

 

[le33sw]

Got the oil changed. This is when the oily nature was discovered!

Is it possible to access the fill plug, without putting it up on a ramp?

Mine must be the OHV, since the engine cover that is present in the SOHC is missing. Did the OHV versions have a LSD?

 

[Blee1099]

You can crawl under the rear and access the fill plug on the backside of the axle. Some models had LSD some didn't, you just need to look on your door plate for the axle code or the axle tag if it still there..

 

[IZwack]

You can crawl under the rear and access the fill plug on the front side of the axle.

 

[le33sw]

would it be possible to fill it (if necessary) by crawling under as well?

 

[96eb96]

would it be possible to fill it (if necessary) by crawling under as well?

Yes, I suggest removing the spare. The plug is on the drivers side, its like over a rib on the rear axle.

Removing that fill plug needs a 3/8 square end socket extension. It can be a pain to get out if it was never opened. It can be corroded in, but it should twist eventually.

They sell bottles of gear lube that are made to get into tight places. Check the level first by checking for gear lube with a finger.

 

[le33sw]

Had another look after a drive, it is worse than I thought. It is defnitely leaking - there was a drop on the floor. I just moved to Canada, and I have absolutely no tools to work with (I am not going to be here for long, so buying tools seems like a non practical solution). I guess I will be at the mercy of repair shops. Made a few calls, got all sorts of quotations.

What is the likely cause - gasket leaking?

 

[Turdle]

Get a picture from the front and rear of the diffy and upload them to a pic host service like
www.photobucket.com

and then link them here. There are a couple of places it can leak. Most likely would be the pinion seal, but it could be coming out of the vent tube, or the cover gasket also.

 

[le33sw]

Ok here goes - took a couple of them198992[/ATTACH]"]

 

[Turdle]

That is definitely a bad pinion seal. Has been leaking for quite a while.

 

[le33sw]

Sorry, the whole post got distorted - is it dangerous to drive? Could I suddenly loose drive to the rear wheels?

 

[le33sw]

Does this mean that the entire drive shaft be removed?

 

[Turdle]

Yes, and then some.
I would recommend some experience in this area before attempting the seal replacement.

 

[Cobraguy]

Don't be surprised if the pinion bearings are bad too. Many times, they get some play in them and that's what causes the pinion seal to leak. Best case scenario is you need a new pinion seal and speedi-sleeve (as opposed to a new yoke). Worse case scenario is you need all new pinion bearings. That requires a complete disassembly of the rear end. Once you do that, you usually can't find a place to stop and you put in all new bearings, seals, etc.

 

[ericautopart]

I've got a kit with all of the bearings and seals in it. If you are interested just PM me.

 

[96eb96]

I would not drive that thing unless I checked the fluid level. If it is bone dry the gears could get destroyed.

As a stop gap measure:
Look at pic 4. Above the axle rib visible in the picture(driver side) is a plug that threads into the axle. I think its visible in the pic.
Get a cheap 3/8 socket and extension and try to remove the plug. It may be hard from that angle.

Fill with fluid until it drizzles out.

As long as the thing is lubed, you are probably safe until its fixed. If its not really gushing out you can drive it.
I think it looks worse than it is. I'm not saying dont fix it but I had a crown vic that I used to top off like that every few months. It lasted 10s of thousands of miles till I got rid of it. Like cobraguy said though, if it does really fail you have a big problem on your hands. For the short term you can add the fluid though.

 

[brooklynchris]

Would there be a similar noise to the ones associated with the symptoms of a bad T-Case if the bearings were shot in the differential as well?

 

[le33sw]

Thanks for the suggestions and tips - what oil is should it be filled with?
Also, is there some soft of a device to fill up with - since you cannot just pour the oil in.