Strange humming/vibration

[dkshartline]

About a month ago I was driving on the expressway and I heard a klunk. It sounded like it came from the front drivers side. It actually sounded like my tire blew out. I hurried up and got over to the slow lane in case my tire was going flat and... nothing. All the gauges stayed good, tire pressure was fine. So, getting back up to speed, I noticed that as I got back over 60ish there was a loud hum. It sounded like tire noise/vibration like when you get a flat but it wasn't pulling at all either way.

I needed new tires and back brakes anyway so I got them the next day- All 4 new tires, all new back brakes (front brakes had been done a few months earlier so they are basically new still). When doing the back brakes I noticed that the drivers side rear bearing was shot so I took it in and had that replaced at a repair shop.

The sound is still there. Every once in a while you can feel/hear it at 50-55ish but it is loud and annoying at higher speeds - mostly over 60-65 (the expressway speed here is 70 and most people do between 70-75). We are going on vacation in just under 2 months so I'd like to figure it out as soon as possible. I don't just want to take it in since they'll likely do a bunch of crap that doesn't need to be done right now when we're trying to save our money for the vacation but we are pulling a camper so it needs to be fixed.

Any suggestions on what I should check out first? It doesn't pull to one side at any speed. I also noticed that when I had some items in the back and in the front that at higher speeds the stuff in the front rattled around and the stuff in the back didn't so I'm thinking it really IS in the front end somewhere.

Thanks for your help.

 

[Explorer_PL]

I had a big clunk one day and it sounded scary. Later on I found that my front end stabilizer link broke and fell off. Easy inexpensive part, maybe $ 20. There are 2 of them, 1 on each side. They are just 3/8 long bolts holding the stabilizer to the lower control arms. If you lost one, the car may be "out of balance", just turn the wheels and take a look.

When my rear bearing went bad, it also messed up the rear parking brake and the rear main brake pads. But if they replaced the bearing they had to take off everything, so they would see the rear brakes.

 

[buckwill]

reproduce the road conditions withour the road and wind noise,, put it oj jackstands and let it roll,, pretty sure u will hear the noise,, id bet on dr side axle bearing front??

 

[banditxp]

if its not bearings then it could be CV joint. i know someone that had a FWD Grand Prix, he would get a hum/vibration going down the highway and it would change if he hit a bump in the road while going at speed.

Does it change at all when you get on the gas hard or hit a good bump going those speeds?

 

[dkshartline]

Thank you for the suggestions. I'm going to get it in the garage on Saturday and take a look at all the things you've mentioned. It would sure be nice if it was the stabilizer link and not something more complicated and expensive!

No, it doesn't change when getting on the gas or bumps. It barely changes when turning the wheel back & forth a bit at speed (though I haven't tried much since I look like a drunk on the road swerving all over the place to see if it changes). The sound it makes is a hum like driving on the highway with huge mudding tires. It seems to kick in at about 60 though I have noticed a bit of a vibration at 50-55, it's like at 60+ it all of a sudden is really there. It doesn't seem to get louder or quieter between 60 & 75 - it's like either noisy or not.

 

[mhallsj]

Ever figure this out? I have the same issue. I saw another post that seemed close to this and mentioned changing the idler pulley. I'm gonna check that out, but looking for other ideas too.

 

[xsportx]

i had the same thing with my sport. I changed both cv shafts and filled her up with fresh oil and now the vibration is gone...

 

[dkshartline]

Actually, we just finally got it resolved completely this week.

We took it to a local mechanic/collision shop and the guy looked it over really well. He checked all the U-joints, the wheels, the brakes, the bearings, etc. He said the whole thing looked good except the rear bearing on the side that we didn't have done yet. He said his gut was telling him that it was the drive shaft but that he suggested we take it to a local trans shop to have them look at it since they have the tools to rebalance it.

We took it into the trans shop and the guy said he would look it over and see what he could do. He replaced the rear bearing/hub and it was still making the noise. He put a used driveshaft he had in it and it still made the noise. He then ordered a new driveshaft from the dealer and it now drives like new. Sounds are gone completely and it drives better than it ever has since we've owned it.

The guy said he did some digging and there is a service bulletin out for it and it's a common problem in the 2005 4x4 explorers. I just did a quick search and sure enough I found this on another forum: Ford Technical Service Bulletin 05-16-4 deals with what they refer to as a vibration/drone/boom at 55-75 MPH. This condition is experienced only in 3rd gear with overdrive off, and is not felt through the steering wheel, more so in the seat of your pants. The TSB covers 2002-2005 Explorer, Aviator and Mountaineer, and the fix is the installation of a "premium balanced" driveshaft (whatever that means).

*edit - I wanted to add that I didn't notice the sound going away with the overdrive off so I'm not sure how accurate that is, but the new driveshaft fixed the vibrations & sound so it must have been the problem.

I hope this helps some of you. There is nothing like having your vehicle have something wrong that you can't just quickly figure out and fix.

 

[dkshartline]

I found this too: http://www.justanswer.com/uploads/bkitchener/2009-07-01_185141_buzzing1.pdf

And this post deals with the same type of thing: http://www.explorerforum.com/forums/showthread.php?t=165693

 

[buckwill]

premium balanced means really expensive, and the one not assembled by the ape with the really big sledge hammer