Thread: humming noise

Wheel bearings? How many KM on it?

It has about 208 thou. on the clock.

Mine sounds like the wheel bearings are on the way out with just under 170KKM on the clock - not sure if you could describe it as a humming noise, but it may be. Jack one of the front wheels up and give it a spin - see if you can feel or hear anything unusual - not the normal disk brake noise you may get, but a deeper rumbling.

Worn wheel bearings usually make a fairly distinctive noise.

Still to try that, funny how it starts soon as the speedo hits 90.

yeah - Wheel Bearing first to check. Diff often sounds similar but the deapish droning/rumbling changes as the power is applied and goes away when power is removed (like most drive line noises). Wheel bearing noise stay constant. As Gav states it is a distictive sound, once you know it you can't miss it.

If its a higher humming - what are the tyres like? Easy to see if it changes after tyre rotate.

Mostly wheel bearings will last 500k - 1000k.
I'd be surprised to see a wheel bearing go at 208k unless the truck has hit some big pot holes, been in an accident or been submerged with faulty seals.

Not sure where you use your truck but I have had similar noises after a stick has lodged between the chassis and tyre or even between the chassis and drive shaft. Sometimes even a stone or rock can lodge and cause similar rubbing. Sometimes a pebble can lodge in the brake caliper rubbing against the rotor giving the noise you describe. Like I said it all depends where you drive. City driving rarely produces these things but us bushies experience all and sundry.

If after you have checked for any extraneous material the next checking method is to lift up each front wheel at a time and drive it to the equivalent speed - this will help diagnose which side or both sides etc.

Has it ever had the windscreen replaced? Every L322 I test drove which had a windscreen replaced at some time made some odd noises at different speeds. Mine gets a low thumping droning over about 120 and is different depending on if I pass a tall truck or a car. The windscreen places always seem to stuff up the trim.

Just an idea.

Originally Posted by jsp

Has it ever had the windscreen replaced? Every L322 I test drove which had a windscreen replaced at some time made some odd noises at different speeds. Mine gets a low thumping droning over about 120 and is different depending on if I pass a tall truck or a car. The windscreen places always seem to stuff up the trim.

Just an idea.

Good point! This reminds me that an incompletely shut sun roof window will also produce a constant speed linked humming noise unlinked to either motor or gear selection.

I've had my heated front windscreen ($2k+) replaced (with no noise symptoms) but they stuffed up the water seal so AAMI is about to pay for another one.