I have a 1995 Ford Explorer. I have a howling/humming noise coming from the rear end of the vehicle. You can really hear the noise at speeds of 35mph-40mph and higher highway speeds. The noise only comes on when you let off the accelerator. As soon as you press the accelerator the howling/humming goes away. It seems to be coming from the rear end of the vehicle. It is not the tires either. I have had it into my Ford dealership like 4 times to have this fixed and nothing. They said they basically went through the whole rear end but the last time they said they did this the problem got worse and a little louder. Any ideas/suggestions? Also, every once in a while when sitting at a stop light/sign my engines rpm go to about 400 and then go back up to 800 or so. It is only sometimes and then it just resumes back to normal rpm's. It drives normal still, but it just drops in rpms every once in a while and sometimes it has a rough idle when it starts but then it has a normal idle as soon as I back out of my garage. I heard some ideas about the MAF sensor, to clean it. Is this hard and does anybody know how to do it?? Thanks!!! Please help, it is getting really frustrating.

 

I have a 95 explorer also, I hear a humming coming from the air intake duct sometimes under the same conditions you hear your noise. I also used to see my RPM's drop low sometimes during an idle.

Are you sure you hear the noise in the back,maybe it's in the front?

I changed my mass air flow sensor trying to solve this and it didn't help. the sensor is mounted in the air intake duct directly next to the air filter. It only took about 5 minutes to change but didn't make any difference (and cost about $200)

I wouldn't change any other sensor unless the check engine light comes on. You could waste a lot of money just guessing.

If you need help in finding out how to read the error codes just let me know. I am pretty good at it, All you need is a jumper wire.

here is a link to a site with instructions on how to read the OBD-1 computer error codes ( this is what the 95 eplorer has)

http://dalidesign.com/hbook/eectest.html

good luck

 

So do you still have your problems with your 1995 explorer? If not, what did you do to take care of them? I am pretty positive the noise is in the rear end somewhere. I guess I can do some more investigating though. Thanks for your info. and if you have done other things to cure these problems please let me know! Thanks again and if any others have any info it would be greatly appreciated!

 

I still have the Humming noise sometimes on hot days when the engine is idling, Nobody could figure it out and it doesn't seem to bother anything so I am letting it go for now.

The fact that the rpm was dropping to about 500 and then increasing went away. I think it was because my EGR (exhaust Gas recirculation) system wasn't working right. That problem turned out to be the $70.00 DPFE sensor (it monitors the pressure drop due to the EGR Valve position) it is a piece of cake to change, But I still wouldnt change it unless I got a check error light and an error code to match.

I would have the rear axle checked out, How often due you have the rear axle oil changed (and did they use the ford additive that is supposed to be used?

 

I don't know about the humming problem, but the RPM's also drop on my '95. It's only every once in a while. It doesn't bother me that much, but I do hate it when the RPMs drop.

N700MS

 

I just had my Ford repair shop go through and supposedly replace my whole rear end of my explorer. So i am hoping they used the Ford additive that is suppose to go in there. I guess I can live with the noise but it would be better if I could just figure out the problem. It just puzzles me since they redid the whole rear end of the Explorer and still the same noise. It happens all the time, no matter what the weather is outside. Thanks everybody for there info and if others have some information on this matter please let me know! Thanks again!

 

First you should get a list of what they actually did to your rearend!
then post it in detail here !

If you still have the noise you describe !
here are my thoughts
You have a pinon bearing or carrier bearing going bad!
But if they haven't eliminated wheel bearings first.
Is this a trac-lok rear /ls ?
When taking vehicles to dealers I always get details of what they touch and what they did ,ask to see old parts also!

Let us know

Rich





Ford Trucks Built Tough!
not with rocks
Watch out "X" Mayor of Truckville

 

They did change the pinion seal and the rest I guess I didn't get a detailed listing. Anyways, I ended up trading my 1995 and just got a 1999 Ford Explorer with 18,900 miles on it. I got a really good deal, I think so anyways, waaaaaayyyyyyy below book. I am hoping this doesn't cause me any problems and if it does I took out a warranty anyways that kicks in when the remaining factory warranty expires in 3 months. It is easier to come up with $10 a month then to pay for an $800 repair one month!! Thanks everyone for their info and help though!!!!!