Hello everyone-

First, a little background to the questions...
The vehicle is a 1996 Ford Explorer 4WD 4.0L. Approximately 3 weeks ago one of the repair shops I use noticed that the pinion seal on the front differential was leaking. Approximately 2 weeks ago I purchased some diffy fluid from my Ford dealer and added it to the differential because the level was low. Last week I got the pinion seal replaced at a different shop that I sometimes use and have been generally happy with. Last weekend, while returning home from a trip halfway across the state (a 3-hour drive) we noticed a noise coming from the front end. I don't really know how to describe the noise - I guess I would say it is like a whirring or scraping noise - it is constant, no rattling or thumping. If I had never driven the vehicle before and was taking it for a test drive I would assume it was road noise or tire noise, but we've had it long enough to know that something isn't right - we've never heard this noise before.

I took it into the shop today - the one that first noticed the seal was leaking - to see if they could figure out what is going on. They couldn't say for sure and referred me to the Ford dealer. They did say (and show me) that the plug on the front diffy has some tiny shavings on it. The shavings weren't there when I added fluid 2 weeks ago - I know that for a fact. One of the guys also said he was hearing a few pops and clunks while taking it for a test drive. He also said when he put the stethoscope on it it was pretty loud where the driveshaft runs into the differential - I guess the same spot where the replaced pinion seal is. He thinks this may be the noise we are hearing.

Here are my questions:
-Is there any possibility that while replacing the pinion seal the other shop screwed something up that is causing problems now? Or is replacing the seal a pretty cut-and-dried job with very little potential for causing new problems elsewhere?

-Is it possible that the low fluid level in the differential a few weeks ago would have caused problems inside the differential that didn't manifest themselves until just a few days ago? Or would any problems have surfaced right away while the fluid level was low?

-If the Ford dealer (assuming I take it to them...I don't want to, but I don't see any other alternative at this point) says the problem is in the differential, what are my options, and what options are best? I know Jasper sells remanufactured differentials - quote I got from a local shop for part and labor is about $1800. Can a differential be repaired? If so, is that a good or bad idea? What about getting one from a junkyard? Recommended or not?

Thanks in advance for any info or advice anyone can give me.

Oh, and the shop today also said the noise we are hearing is definitely *not* bad wheel bearings - they checked that possibility out pretty thoroughly.

 

Replacing the seal a pretty cut-and-dried. I can't think of anything they could have done to mess it up, not saying it can't happen. I would take it back to the shop that replaced the seal and have the look at it.

Differential can be repaired, but that depends on what is damaged.

Did they pull the front cover? If so they mite have pulled the Differential and not put all the shims back in, this could be the problem. This will make the differentail out of alignment from the old setting. You need to have it pulled back a part and take a real good look at it. Look at the gears, look for new shine or chips.

 

The noise is coming from the bearings in the differential. They said the differential needs to be replaced. $1200 for a used, 1-year warranty. $2000 for a remanufactured, 3-year warranty.

 

There trying to take the ez way out. Just put new bearing in, it's a lot cheeper. Can be done under $500.00. I did my ranger and it ran around $275. Look at some of the 4x4 shops, they do that kind of work all the time.

 

I just called my local Ford dealer and talked to somebody in the service shop. He said in most cases it's better to overhaul/repair the differential rather than replace it. Problem is, he obviously can't give me an exact quote because we don't know exactly what is wrong inside the differential.

He said to remove the differential, get it open, and figure out what is wrong, I'd probably be looking at about $450 in labor. Parts costs will depend on what needs to be done, and he probably wouldn't charge me any more in labor than the initial $450. He said it's likely the final cost would be $1000 or less. Once it's off and taken apart, whatever is bad definitely needs to be replaced though - it can't be put back together with the old parts - which makes sense I guess.

So, I think that's what I'm going to do. Hopefully he'll be right about it being under $1000, because that's about all that I'll have when I take it in.