Zoom zoom noise coming from middle to rear end...

[MarkMatters]

Yup, the noise takes place all the time while driving...it never bothered me until my dad used to lib...he said it was something serious...while going 50 is where its most noticible...a zoom. Zoom zoom sound. When i brake, it goes from zoom. Zoom. Zoom zoomz zoomzoomzoomzoom until i stop completely....not the tires, thats another sound but i can make them out. Any ideas?

 

[jnaut]

Yup, the noise takes place all the time while driving...it never bothered me until my dad used to lib...he said it was something serious...while going 50 is where its most noticible...a zoom. Zoom zoom sound. When i brake, it goes from zoom. Zoom. Zoom zoomz zoomzoomzoomzoom until i stop completely....not the tires, thats another sound but i can make them out. Any ideas?

I'm a little confused here. Like a revving? And it happens when you brake? My Libby is currently in the condition of needing a new Pinion Bearing (cost ranging from $650 to $1,100 depending on the shop I choose). It makes a sound similar to being followed by someone with a leaf blower or small scooter. However, its pitch rises and falls with your speed. It doesn't go 'zoom zoom' while you're maintaining a consistent speed.

In general, differential problems can sound like a whine or buzz coming from the rear center area. And yes, they're not particularly cheap to fix.

 

[maverick7321]

Are you sure you don't have a Mazda stuck under your Jeep trying to get free?

 

[Jeepin05]

Sorry but the Mazda joke was perfect...Zoom Zoom.

I hope you can figure out what the issue is, I would visually check everything mechanical around the suspect area. U-Joints/Rear Driveshaft, Rear Diff, Rear Brakes. Does it happen to change based on how much gas is in the tank? Highly unlikely, but maybe the fuel pump?

If it doesnt make the noise in park, I would assume it's part of the driveline somewhere...

Good luck.

 

[Powerslave]

My pap had this problem with a pickup, and it was the balancer on the drive shaft. I don't think it's really a ZOOM ZOOM sound, but more like a mmmMMMMmmmMMMMmmmMMMM something like that?

 

[bigBlue]

i had a thump thump noise coming from the rear end when driving at certain speeds. More of a harmonic sound that changes with speed and breaking. Everyone thought it was a hub bearing but no garage in 3 counties can figure it out, and since all hub bearings are sealed, no one wants to do the leg work to figure it out.

 

[flair1111]

sounds like a bearing.

 

[bigBlue]

sounds like a bearing.

thats what I think too, but like i said the only way to find out is to replace it. Its a really big price to pay for a "diagnostic check" though. I was told by the 4x4 shop that since the hub is sealed, the damage is contained and to only replace it if i was made of money or sick of the noise.

 

[JeepJeepster]

If the noise gets faster when you break then it shouldnt be a bearing.

Have you checked the brakes? When was the last time you replaced the diff fluid?

 

[MarkMatters]

Mazda..ha love it. It does sound more like a mmmMMMMmmmmMMMM sound...i thought it was a bearing At first...i just changed the diff fluid wishing tjat would fix it...no luck...breaks got replaced a month ago...im pretty sure it s something in the driveline...since
It only does it while running...and it does get faster while braking till it comes to a complete stop...appreciate your input, haha yeah...my dad mentioned some of these things as well...but im not too happy with the numbers it would cost to get it checked/fixed...i will be focusing more on it tomorrow, and get under it and givr you guys more details amd see if we can troubleshoot this thing...thanks!

 

[tjkj2002]

i had a thump thump noise coming from the rear end when driving at certain speeds. More of a harmonic sound that changes with speed and breaking. Everyone thought it was a hub bearing but no garage in 3 counties can figure it out, and since all hub bearings are sealed, no one wants to do the leg work to figure it out.

The rear axle bearings are not sealed,just normal roller bearing on each end,it's the front hub bearings that are sealed.Takes less then 1 hour to change both out,new axle seals and gear lube are needed.

 

[sport]

You are describing something similar to my issue. I noticed that my u-joint on the rear driveshaft is "bad". I say bad because I compared mine to my wifes Kj and hers seals are good and no grease is visible. So I ordered a new one I will let you know after I install it if that clears up my vibe issue.

 

[eebee]

My '07 has started to make a med-high pitched humming sound that came from the rear of the vehicle. It's not a really loud hum, but noticeable. It only happens when I have my foot on the accelerator and stops when I take it off. My friend/mechanic says it is the rear pinion/bearing and recommending I have it fixed before something happens and causes a lot of damage. He also said this is a known problem with the Liberty. Has anyone else heard this before?