L322 Whistling noise

Hi all

I have A 2004 L322 4.4V8 vogue 100k miles and it has a terrible Whistling noise when you go over 20mph.
The Whistling changes pitch if you go over say speed bumps, but always stays at the same volume no matter on speed. It will still make the same sound if car is put into neutral and in free wheel.

It does not grumble, wine or squeak all gears change ok, no codes or dash lights, high and low range works, it perfect apart from this Whistle.

At first i thought it to be something to do with the brakes, as it the same sound you get when pads get on the old metal wear indicator. so Ive had all the brakes discs and pads changed, new rear caliper plus new hand brake pads as well to no avail.


A few days ago i had it up on the ramps, the mechanic did some checks, as he was turning the prop going to the transfer box it made a faint Whistling noise, like high pitch metal on metal very similar to the Whistle i get when driving.
Oils was check and ok, car has lots of history along with a full fluid change less than 5k ago at a LR garage.

He is unsure if this is the possible cause of the Whistle im getting under load so i ask for your help,or any info on possible diagnostics, could this Whistling noise come from the transfer box case.

Many thanks in advance for any info on this.

Nic.

prop shaft ujs?

Put back on the ramp, run the car in drive, should expose anyodd noises,

Trasfer boxes are rare to go wrong, although you have no idea of the life that car has had,

IYK500010 should of been used, look for that on your invoice,

The rear prop has a bearing on it for support, these have been known to go south.....could be the bearing whistling.

As ovalander and saint posted, check the cheapest options first.

Thanks all for replies, I'll check the above out.

Nic