Bearing hum from rear?

[Blubayou]

Hi Guys,

Coming up to 106'000 and my faultless 406 est has a fault!

This has been developing for a while, and is getting worse (over the last 10'000 or so).

A resonating hum from the rear, possibly offside, which starts about 45mph, hits a resonant 'hmmmm' peak at 54mph & then sinks into the background as speed increases. It is more pronounced with weight in the back but does not seem to change on cornering.

To me it sounds like a wheel bearing, but I feel no play with the wheel jacked up, not graunchy either. I understand these rarely fail?

I have had the offside off today, it was pretty dry on the outer race. Attempted to fit new bearing but the new assembly fell in half on vigorous fitting! Before I destruct things further, should I be looking elsewhere?

[Doggy]

This usually turns out to be an out-of-shape tyre, (it's happened to me several times) - try swapping both rears alternately for your spare.
It may not be this, but since it costs nothing you really should rule it out first.

[rwb]

I thought bearings were normally a narrow speed range, and at multiples of particular speeds?

[PeterN]

Generally the noise will get louder with increased load, so cornering to the right will throw the weight on to the n/s wheel and vice versa. Listen when the noise is present and see if cornering makes a difference.

Peter

[Blubayou]

Well what can I say?

Thank you Doggy

Removed the O/S rear 'Sunny' tyre (24'000 miles 3-4mm tread, Chinese crap), fitted old worn Pirelli 6000 spare, no more hum!

Pair of new tyres for the rear methinks

[Doggy]

That's how we roll.

[rwb]

... 'Sunny' tyre ...(24'000 miles 3-4mm tread, Chinese crap)

I've had trouble with them

Glad it's sorted

[PeterN]

Easier and probably cheaper than a wheel bearing. Well done.