Noise at 50+mph - bearings, ******?

[RedJeep]

Just replaced the tires with much quieter ones. The old set were mismatched brands and had varying degrees of wear with some old cupping. The new set is delightfully quiet up until about 50. That's when I hear an annoying noise that I think was all garbled up with the older beat up set of tires.

At around 50 to 55 when I'm cruising along if I lift my foot off the gas pedal just a touch and disengage the motor there is a somewhat high pitched warble/ wawawawawawawawa noise. When I lightly touch the pedal sometimes it peaks and then when the motor is engaged again it goes away. Any thoughts? I just picked up this Jeep a few weeks ago and did buy the 12 month unlimited mileage warranty for the engine, ******, diffs, and other major mechanicals.

From all seasoned KJ owners, does this sound familiar or like something is breaking?

Many thanks,
Dan

 

[rockymountain]

Usually 50+ noise is intermediate shaft and/or passenger side CV. How about a little about your KJ so we can aim at something.

 

[apukareem]

Check out your wheel bearings/hub assembly as well

 

[RedJeep]

Thanks for the very fast replies.

It's a 2004, 3.7, automatic, 4x4. 114,000 miles. The new tires are nothing spectacular but new from a car dealer I do trust. 90% of my driving is highway so I wanted a quieter tire. They are a basic set of Roadian HT SUV tires. P235/70R/16

Thanks,
Dan

 

[rockymountain]

you have about 5 things to check. wheel bearings on both sides, cv on front driveshaft, both sides for cv joints and passenger side intermediate shaft. that's if you know its coming from the front. to rule out the front driveshaft, remove it and take a spin (don't put it into 4x4 while its out).
Try to pinpoint where its coming from first.

 

[RedJeep]

Thanks. I'll look into those things.

Dan

 

[osufans]

I was gonna suggest what RockyMountain just said. I have the same type of noise at about 40-50. However, when I pulled the front driveshaft, I could tell the noise was still there.

I have noticed my front rotors are warped pretty bad, and who knows what else. I plan on doing brakes soon, and replacing some bushings that are shot. I'll dig into the issue more when I do that.

 

[RedJeep]

Noise problem solved. Turned out to be the spider gears in the rear diff. The used car lot took care of all costs and even loaned me a CRV for a few days while they really checked out the issue. Oh, how sweet the quiet ride is now! No more annoying screech/whine at 50+. The Jeep also seems to fly up to 70mph now before I know it whereas before 55 felt like I was climbing a steep grade. I have no idea what this would have cost. Wonder if I'll get a mile or two more per gallon. The dealer even washed, waxed, and detailed the Jeep for me. If anyone is in Southern Maryland needs a really great used car dealer I can send you a link to them.

Dan

 

[TwoBobsKJ]

That's great service there - kudos to the dealer for standing behind the sale. (Dirty little secret: They DID get paid handsomely by the warranty company for their labor & parts so they certainly didn't lose anything :smokin: )

Still, you will refer lots of people to them because they supported you.

Bob

 

[RedJeep]

Oh, I'm sure they're figuring out how to keep paying the bills, but, yes, they followed through. So nice and quiet now.

I'm thinking this is also a reason why the Jeep sat on the lot for a while before I bought it. When I test drove it it was very loud. I figured it was the aggressive and partially worn tires alone. I'm sure that played a part in it but I think the bulk of the racket was from the gears.

Dan