Thumping noise/Steering wheel vibration

[Stick_man]

I have a '98 Explorer XLT v6 sohc 130k miles.

I have a thumping noise that seems to speed up in frequency as the truck accelerates at highway speeds (thump ... thump ... thump.thumpthump thump.) It's especially bad when I take my foot off the gas. It also causes the steering wheel to vibrate.

It does not pull one way or the other. I had rear brake pads installed on old rotors 4 months ago and, a new muffler a couple of weeks ago. The tires are 2 years old and have never been rotated, but I probably drove only 9k miles on them in that time.

What is this?

 

[my98nnj]

Rotate the tires, front to rear and inspect them for any irregularities.
If the noise is gone, you've found your problem.
If the noise is still there, start looking at the drive line components, wheel bearings, ect.

 

[Stick_man]

i checked the tires and they look fine. It does it when i apply the brake now. it has to be the rear brakes/rotors, but it seems like it's happening in the front.

the tech told me he likes to replace rotors with pads, when i got it done a few months ago, but he forgot to include it in the work order. he told me 30 minutes into it. i told him to go ahead and do it without since it was already $300 with oil change and inspection, and new rotors seemed like BS to me. I guess I was wrong or am I?

Could it be the pads not sitting well with rotors? And I guess it will just go away by itself? how about cleaning them with brake cleaner?

 

[Willcall]

It could be several things... if the tires look fine check the bearings, rotors, and calipers. On my 98, I had a similar noise to yours. It turned out that the driver side caliper had come loose and now being held on by one bolt. Scary. The rotor shouldn't be too much of a problem. My mom drove our 02 for 3 years with warped rotor before telling anyone. No problems with it what so ever.

Also, is it a 4x4?

 

[Stick_man]

yeah it's 4x4.

i wonder if the rear caliper has come loose? It has already been a couple of months since the rear brake work was done; and I didn't really drive that much since

i would think a bearing would do it all the time; not just highway driving when brakes applied, no?

 

[Willcall]

Check the entire 4x4 system and brake calipers. I've heard of clunking coming from the front with 4x4 models. And it could be the reason you have shaking from the steering wheel, yet no pull to either side.

 

[lorelei2011]

It's most likely your rear universal mine was doing the same thing had it replaced it was just about to let go no more problems I had the thumping and vibration in the same manner you described and I no longer have either problem. It was quite scary till we figured out what it was.

Check it as soon as possible I'm very lucky mine didn't go on me and cost me a lot more money then replacing it did.

 

[yavapaires]

Tires can "look fine" but still have a separation. You really need to jack them up and run your hand around them feeling for a high spot. It probably will not go all the way across the tread, but could be just on one side of the tread, maybe 1/3 to 1/2 way across. You do not need to ask me how I know about this, it is probably because I have had the same problem. But, don't rule out a bad brake caliper.

 

[Stick_man]

I went to pep boys and got a "safety inspection" for $20. They want $1500

They want to replace all the front pads, rotors, calipers, struts and bearings

They claim that one of the rotors had a crack and the caliper is grabbing it.

The thing is I just replaced the struts, rotors, and pads on this truck 2 years ago and barely drive 4000 miles a year.

As much as these idiots are probably just part changers, there is some truth to crack in the rotor(s).

This type of crack appears on both rotors however. see pic.

for the fingernail test .... how fast are you suppoed to run a fingernail over? If I run it over slow it will get caught in there

 

[yavapaires]

How fast is of no concern. You must replace the rotor immediately! You are opening yourself to more than serious problems.

 

[Stick_man]

both front rotors are like this. I bet this is the problem. i think I'm going to replace them both, and then see how it drives. thanks all.

 

[97xxxploder]

u dont need to do a fingernail check on that. those need replaced ASAP!! if u r slightly mechanically inclined it is an easy and inexpensive fix. rotors r normally 30-40 bucks a piece and u can get p[ads for about another 20-30. jack it up, take tire off, remove caliper,nomally 2 bolts holding it on, and then rotor should come right off. might need to hit it a few times with a rubber mallet. mine came right off. i changed the front brake pads and rotors and also squeezed in an oil change in under an hour. pretty easy with the right tools. and can save u a lot of money. places like pepboys have to repair things to a certain regulationg which mean they will replace anything they want and then charge bookoo dollars. they wanted 1500 just to put rear seals and fix the e-brake in my ranger. i told them to get lost! but anyways. definitely change them rotors and get new pads before its too late and u have 3 times as many problems to fix.

 

[Stick_man]

Worked out well w/ some duralast parts. The rear tire has a slow leak/flat too, but once filled up, the truck runs goood now. Thanks all