Driveshaft noise but maybe not???

BritinNorway said:

Hi all,
Need expert landy ears and advice please. D2 2004 4.0 V8.
I have a whirling/chirping noise from in/under/around engine. And yes, my thoughts too were driveshaft. Had it off, all seemed good, replaced one UJ. But the noise persists.
The noise:
- is only whilst the car is moving
- seems to disappear around 60mph
- has no vibrations with it ever.
- Doesn’t speed up or slow down with speed.
- is difficult to pin point location as only is apparent when car is moving.

any thoughts / experience of this?
My thoughts are perhaps pullies on front end (making noise under load of accelerating), centering ball in driveshaft although appeared ok, SAI pump, ……?????

my thoughts are to just buy a whole new driveshaft to stop worrying about it. But it will annoy the hell out of me to do all that then drive away and the noise it’s still there, flicking me the bird.

Cheers guys. Any help most appreciated.

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Stanleysteamer said:

I would say, think hard about your phrase "Doesn’t speed up or slow down with speed.".
If this is really true, it eliminates any part of the engine, as the engine is always speeding up and slowing down as you rev it, it also tends to eliminate the running gear as that too is always speeding up and slowing down.
About the only thing that turns at a fixed speed is the heater fan. But that turns when the car is stationary. Then you may have to consider any other type of pump like the ACE pump, any self- levelling pump you may have possibly even a fuel pump.
Other things to consider may be wind noise from a loose cover under the engine, brake back plate, viscous fan, or maybe wheel bearings. I've just had the latter and it took me ages to find out which one it was, but that DID alter with road speed.
Best of luck with it.

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BritinNorway said:

many thanks for your tips! It’s funny as I did think about that “speed” comment a bit. But you’re right, difficult to express correctly and can have different connotations. I guess what I mean is that the speed of the car doesn’t seem to influence the sounds intensity. For example at 60 the sound is t twice as fast or loud than at 30. It’s actually almost the opposite. Louder at slower speeds. Then pretty much disappears at circa 60mph. But sometimes not. Which makes it so tricky. Feels like there is no rhyme or reason. Except movement.
I’ll give a think about what you suggest though. Perhaps wheel bearings, but sound doesn’t alter if go round one corner or the other. cheers

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