HI all, I've got a bit of a problem with a speed related transmission-style whine. Wasn't like it when I bought it & drove it home, just seems to have arrived all by itself. - deep joy !!!

Comes on after a couple of miles at 50+ mph and gets louder with more speed but then goes slighter quieter again above 75mph, does not do it on overun, only when throttle applied. It's not vibration it sounds more like diff whine. Does not seem to vary depending on corners, seems pretty consistent.

This is what I've done up to now, to try and identify where the noise is coming from:

1. Greased all propshaft nipples - no change;
2. Changed the oils one at a time, front diff, then trans box then rear diff and put in 85w-140 - no change
3. Re-oiled the autobox - no change;
4. Checked all four wheels for bearing play, not apparent;
5. Swapped all four wheels for known good ones - no change;
6. Swapped front propshaft for known good one - no change;

Anyone got any other suggestions as I'm losing hair and temper fast & she's a lovely car apart from this?

Dave

I think U've done every non-invasive procedures U could. It seems it's an internal matter presumably of Diff or transfer box (if you are certain that the hub bearings are in good shape, albeit these are more sensible on cornering)

sierrafery said:

I think U've done every non-invasive procedures U could. It seems it's an internal matter presumably of Diff or transfer box (if you are certain that the hub bearings are in good shape, albeit these are more sensible on cornering)

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Thanks for that SF, the problem is - where do I start? Identifying where the noise is coming from seems to be nye-on impossible.

I put the thicker oil in each diff and the trans box - one at a time - in an attempt to see if it modified the noise, but no.

I'm getting a bit tired of this to be honest as I can't track down the source.

If I had a centre difflock (it's a 1999 so I'm assuming the internals are there) I would probably removing the props, one at a time, to see if I could isolate whether it's coming from the front or rear diff.

Any thoughts anyone.............................................?

UP - HELP !!!!!!!!!!!!!

thebiglad said:

If I had a centre difflock (it's a 1999 so I'm assuming the internals are there) I would probably removing the props, one at a time, to see if I could isolate whether it's coming from the front or rear diff.

Any thoughts anyone.............................................?

UP - HELP !!!!!!!!!!!!!

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That's the way to do it....I know there is a procedure to lock the diffs accessing directly the diff lock spigot(I just heard about it, go under the car U can feel the spigot with your hand if U reach up onto the transfer case......and here my knowledge is over) Hope some mates will come with further advices........Once U've locked it U can remove the props, one at a time......and then U will see where's the snag....I keep my fingers crossed for U because this seems to be an uncommon malfunction.

Bit late to reply to this but, my 1996 diesel auto does the same thing. Always has. A high pitched whine that comes and goes ay higher speeds as you apply power. Its from the transfer case and I was told by the dealer that its normal. I have never had any problems. I live with it, as it only occurs at expressway speeds.