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I have a 2002 Ford Explorer.In February 2008 I was told i needed a new differential. I did not fix it at that time. Mileage was 102,000. I’ve put 10,000 miles on since then. Should i invest the $1300 it will cost to fix it, and if I don’t how long will it be before the dirrerential fails and is it safe to keep driving it as is?

What did they say is wrong w/ the differential?

These things don’t normally fail before 300K as long as they don’t run out of oil (and sometimes even if they do)

there was an airplane sounding noise coming from the right rear of the car.
they took it for a road test and said noise from inside rear differential,
needs unit. Also on the same inspection they replaced the right rear tire rod assembly. Are these somehow connected? Anyway, that’s it. I also had the right rear hub assemply replaced in May 2006 and that had the same airplane noise coming from the rear.

More likely a bearing noise. Probably doesn’t need a whole “differential” but just some bearings. As bearings go bad they shed metal particles that get into other bearngs and gears. The longer you wait , the more parts you’ll need. Get a second diagnosis or get your trusted tech to actually take it all apart to correctly diagnose.
On my old 91 Explorer, I brought it in the shop thinking u-joint noise. My tech put in a pinion ouside bearing only, and the noise was fixed. Noises travel through their neighboring parts and can fool you until dis-assembled.

Thanks, I think this bids a second opinion. It’s infuriating not knowing if the dealer is getting over on me. As i’m looking through my car records i also see there was a rear pinion seal replaced last December. Any connection?

The tricky part about going to a dealer is, some jobs are labor-intensive to the point where Ford’s service writers say to just replace the whole thing.

IMHO, a diff R&R doesn’t have to be a dealer job, regardless of the age of the car. Look in your phone book for auto repair, and then find someone who offers differential service (most towns have at least one place that caters to setting up diffs), and let them take a look at it. A few years ago I built a '72 Ford F-100 4wd, and I found a heavy truck shop that had some free time, they gave me a great deal and did a good job setting up the differentials.

Thank you so much for your advise!
Have a good day

Any clarification on the “right rear tire rod assembley” maybe a typo, but a rear tie rod on a Explorer? is this a multi link rear suspension?

Go to an independent mechanic, possibly a specialist if you can find one. It may be rebuildable. Consider installing a take-out from a scrap yard.

If you indeed need a rear end, I would replace the entire unit, brakes and all, from a salvage yard.

And YES, replacing the pinion seal can be tricky… Usually, a new “crush sleeve” is needed to properly pre-load the pinion bearing. Removing the drive shaft yoke from the pinion gear so the seal can be replaced, and then properly re-torquing everything can be tricky and lead to problems. With differentials, you are ALWAYS better off with a factory assembled unit…

Thanks for all your opinions!!
I did in fact go to a local mechanic that specializes in differential. Unfortunately I do need to replace the unit but he can install a rebuilt at half the cost!!

So glad i checked on line, before i went back to dealer!!

Have a good day!