Intermittent Low Frequency Hum from Rear

[Derook]

Help! I have a strange humming noise coming from the rear of my recently purchased 2003 RR. The best way I can explain it is that it sounds like a foghorn or a bass speaker that resonates inside the cabin and appears to come up through the floor board near the back passenger wheel area. It can get pretty loud at times. The weird thing is that is only happens intermittently at around 30 and 40mph. I've been able to produce the sound by slowly accelerating and keeping the speed somewhat constant. If I can keep the same speed I hear it for a longer period. It is more pronounced at 40mph, especially after being at 45 or higher, then dropping gear and going easy on the accelerator down to 40mph. Also seemed louder uphill.

It sounds a little similar to other posts I have read, but there really is no significant vibration. The car drives perfectly fine otherwise, and at other speeds. I read up on wheel bearings, differentials etc, but none of the symptoms exactly match. No squeals, rattles, grinding, knocks, etc. I have not had a chance to look at the tach when it happens, but will be doing so tomorrow to see if there is any correlation.

The tires are Hankook's on 19" rims (they came with the car). Has anyone ever comes across a similar situation? Could this just be a bad tire set up or signs of a more serious problem? Any help would be greatly appreciated.

Thanks!

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03 Range Rover HSE Adriatic Blue
Ex - 04 Discovery SE
Ex - 99 Discovery II

[lsawicki]

I would check your U joints. I had a higher pitched whining and I had a U joint that was about to fall apart. I wouldn't recommend driving your RR unless necessary until you get this problem check out.

[Derook]

Originally Posted by lsawicki

I would check your U joints. I had a higher pitched whining and I had a U joint that was about to fall apart. I wouldn't recommend driving your RR unless necessary until you get this problem check out.

Thanks lsawicki. Was your problem also intermittent at certain speeds? I hadn't considered the U joint. I had one that went bad on my Discovery a while back, but it was in the front and caused a noticeable clinking sound and a shake in the steering, also intermittent. Got it to the mechanic in time though. I did not realize that the vibration in the rear is less pronounced. Haven't heard the clank going into drive or reverse yet, but will check that tomorrow. I'll keep it parked until I can get the the shop later this week. Hopefully I'll nail down the issue soon.

Thanks again

[Rasheed]

wish folks would update if they solved a problem and share the solution with everyone!