Just got a used 2002 Explorer who's rear end seems to hum when the car gets up to speed. The faster you go the higher the pitch gets. It sounds like it is coming from the differential but I can't tell because the sound bounces around the cabin. I've been other Explorers with the same problem but this is pretty loud. Any advice?in

 

I have this exact same problem. I just bought mine a week ago. I noticed my right rear tire is cupping so I think it may be the shocks or something. I'm sure this truck has mutliple issues that will surface.

 

i get the same high pitch humming sound... sounds like from the rear axle...

also my ABS light is on... stealership cost $75 to check, time to go to epboys/kragen.. for free...

 

Usually, a humming noise from the rear end is due to one of two problems..

1. Especially with the independant suspension in 2002+ Explorers. Alignment or shock absorber problems causing tire-cupping. Tires make a lot of noise if they're messed up. Run your hand over the riding surface of the tires(not if you see metal threads!!!) If the treads are fairly smooth without ugly cupping or other surface deformities, they are probably ok.

2. Differential's have any number of bearings that can give out, not to mention ring and pinion gears that wear out and start making noise. If it's a differential problem, it really would be worth your time and money to pay someone who knows what they're doing to fix it. I can say that an Explorer rear end may be cheaper in the end to replace rather than repair. If it turns out to be rear end, take time and weigh your options before you make a decision.

 

They are know for having rear end problems, but yea start with the tires first,

certain tires can make a heck of a racket at high speed an sound very close to a brg. thats about to fail,

an if the tires are worn funny that will also cause a noise

an if your anti lock lite is on its a very good chance that the lil pick up magnet has a small flake of metal on it shorting it out , there real easy to remove , just unscrew the one bolt holding them in the top of the diff , un- plug the wires , an pull the senser out an take a peek at it, If its gots lots of metal on it I would say you need to have it looked into for possibly a problem, other wise just wipe it off an reverse to install , an disconnect the battery to trip the lite .

 

My 1995 Explorer has made this noise (high pithced whine) since I bought it 4 months ago. It seems to only come on at speeds over 50 MPH and comes and goes with the throttle. If I am on the highway but off the throttle, no noise. If I just barely apply throttle, it comes back. Tire wear is fine so I am thinking a rearend problem, but it seems to run fine.

 

OK. The noise has gotten progressively louder to the point I took it in. Diagnosed with a bad bearing (pinion or carrier). Estimate was ridiculous at $900-$1440. I am looking into a used rear end. I live in CO, any recommendations? Also, is this uncommon to have happen in a 1995? I know the 2002 and up had a lot of issue's. Doesn't look to be a really difficult job to replace. Anyone done this?

 

Well, not much response in this forum on the topic at hand, but if anyone cares, I had a used axle with 59k on it installed for $640. That included labor and synthetic gear lube. Pretty cheap considering I called around boneyayrds and was quoted around $500-550 just for the axle.

 

From my experience. I had a really loud humming noise coming from the rear. It ended up being a pinion bearing. It somhow got a couple scraps on it and caused the whole mess.

 

i had this problem; it started out with slivers of metal in the rear diff fluid. progressed to loud noise, i guess the crush sleeve in the rear was not put together correct. took to dealer, cost about 1200, replaced bearings, took it in the shorts on that one. Driving it away, i found when i got above 70 rear end shimmied and made lots of noise; dealer insisted it was wheel balancing (lol). I made them work on it and they hooked it up to their super duper machine which told them the noise was coming from...the rear differential, duh. The took it apart again, said the pinion gear needed to be replace, and they would only charge me the difference in labor between repacing the bearings, and the gear, what a deal! (there is no extra labor). I called ford, complained, and they did it for free, minus the cost of the part. Problem solved, ran good, then a year later, same problem cropped up, took it back, they fixed it for free, mechanic said, once again, the crush sleeve was not aligned properly. Has been running great for two years now.
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