[Jaz]

Hey all,

My truck has had a slight background rumble that has been hard to pin down for the last year, and in the last week or so its now turning into a faint whum whum whum noise which makes me think it's a wheel bearing.

Going slowly there is a faint intermittent clunk from the rear end, which makes me think it may be the rear dif.

Any tips or pointers as to what else it may be? I've got the stuff to replace both rear wheel bearings if necessary, and will be going to see a mechanic dude (chinese guy here in Richmond) on Monday about the noise (unfortunately don't have the workshop space to diy here), so any heads up for things to look out for?

Also, any idea how long it takes to replace a rear wheel bearing? Or any alternatives that might be an idea. Gotta watch my budget, having twins in July!

Clutch is also on its way out, but no real change in noises depending on whether it's in or out, so I've discounted that.

Thanks!

Jared

 

[Ryno]

run it on a hoist and listen with a stethoscope. it should be pretty obvious

 

[Jaz]

Fair enough, thanks Ryno.

 

[crazycanadian]

run it on a hoist and listen with a stethoscope. it should be pretty obvious

noises like this never are unless they are really bad... ususally a drive line noise needs to be driven on the road with load on it... I hate doing drive line noises since they can be so tricky to pin down.. My shop has Chassie ears that we can hook up to different points and listen for noises while driving.. even with that it can be tricky..

Does your noise change when you swerve side to side? or does it change when are on or off the gas??

 

[Jaz]

Hey CC,

When driving down the parkade (I park three stories underground) I notice the noise less when turning the corner, more when on the straight descent - it's the same with clutch in or out though, and on the highway it's the same under accel or decel. Did notice a slight rumble under my feet when lifting off the gas but not quite a little while ago, but figured that would be the worn out clutch.

The whum whum noise is certainly becoming more noticeable on the highway over the last few days though.

I'll do some more road testing and swerving on Monday morning... look out drivers on the 99!

 

[Jaz]

Strike that, it does it no matter which way I'm turning at low speed, and actually now has an audible regular soft "ker-klunk" coming from the back end.

 

[Ryno]

noises like this never are unless they are really bad... ususally a drive line noise needs to be driven on the road with load on it... I hate doing drive line noises since they can be so tricky to pin down.. My shop has Chassie ears that we can hook up to different points and listen for noises while driving.. even with that it can be tricky..

Does your noise change when you swerve side to side? or does it change when are on or off the gas??

i hate the chassis ear. we had one at toyota and got rid of it. we still have the toyota NVH, it kinda helps, but i still have the best luck with a stethoscope. mind you i have rebuilt a couple thousand diffs and have become accustomed to finding noises. each to their own i guess.

 

[bcsavage]

Kinda far fetched but I thought I had driveline issues on my old cherokee. Replaced wheel bearings, lowered my t-case. Nothing. Turns out the "whoob Whoob" sound was an exhaust leak resonating near the back.

 

[Jaz]

Just took it to the chinese guy that a mate had recommended. We went for a quick spin (him driving) in which he couldn't hear the noise, came back, had a look round the back, then he about gave up saying "Ees too ol'. Just dri'. Wait for big noise. Once start fix, sometimes soft parts inside, fix more. Just dri'."

Righto. Well, I'll take his opinion for a bit, then see if the noises change. I should have driven to show him the noise at low speed - it's right there, a klunk... ker-klunk... klunk... coming from the back end somewhere.

Savage, the exhaust is pretty farked on my vehicle, so that could be a potential for the whum whum at highway speed, although it's only really developed in the last couple of weeks... unless I put another hole in it on our last camping trip.

 

[bcsavage]

Savage, the exhaust is pretty farked on my vehicle, so that could be a potential for the whum whum at highway speed, although it's only really developed in the last couple of weeks... unless I put another hole in it on our last camping trip.

anything is possible. I will say this, it's hard to diagnose driveline issues when all you hear is exhaust

 

[Jaz]

Ha! Actually, it's not that bad, it's just got surface rust from the cat back, and you can hear it rattling occasionally on startup. No noise audible from the cab when cruising though...

 

[bcsavage]

surface rust is no biggie. It's the connections you want to focus on.

 

[trialspro]

If it is the wheel bearing, they aren't TOO hard to replace. I did my driver's side two weeks ago without the use of a press. You just need basic hand tools, a dremel and a cold chisel.

I have the whum whum noise as well, somewhere from the rear end Mine doesn't clunk though as you says yours does. I keep hoping it'll get worse and be easier to pin point, but it just won't happen. I'm starting to think my wheels may need rebalanacing.

 

[crazycanadian]

If it is the wheel bearing, they aren't TOO hard to replace. I did my driver's side two weeks ago without the use of a press. You just need basic hand tools, a dremel and a cold chisel.

I have the whum whum noise as well, somewhere from the rear end Mine doesn't clunk though as you says yours does. I keep hoping it'll get worse and be easier to pin point, but it just won't happen. I'm starting to think my wheels may need rebalanacing.

check your tires for cupping... whum whum noise could also be tires noise.. does it change when going around corners or on off the gas??

 

[trialspro]

haha i don't wanna hijack his thread, but i'll look into the tire issue.
thanks

 

[Havikon89]

i had a very similar issue, i went to change my oil pinion seal and saw that my yoke was loose. 30mm socket fixed it right up. Check your tires for the humming sound, P.S i have a clutch for you for cheap. it was replaced less then 20,000 kms ago on the motor i just pulled. shiny new pressure plate it worked fine