E39 M5 slight whine on constant throttle....
E39 M5 slight whine on constant throttle....
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humpbackmaniac

Original Poster:

1,898 posts

265 months

Wednesday 7th April 2010
quotequote all
On a smooth road I get a slight whine when holding a constant speed, diff or prop bearing do we think? It is getting a little worse per 1k not enough to worry yet but annoying none the less. I dont think it can be a rear wheel bearing as it appears to be drive train stress related.


Or it could just be the fuel gauage dropping! smile Worth every penny though


Neil.D

2,878 posts

230 months

Wednesday 7th April 2010
quotequote all
Have you checked the diff from underneath?

Just thinking - if it has lost a lot of oil they can whine. Does it look wet when you're lying on your back underneath?

humpbackmaniac

Original Poster:

1,898 posts

265 months

Wednesday 7th April 2010
quotequote all
I havent yet did check the oil about 6k ago. I'll ask the cat to take a look.

Sorry I jest, thanks for the info, i'll take a look at the levels, need a ramp though.

Roan

527 posts

225 months

Thursday 8th April 2010
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Sounds like the problem I have - it's driving me insane! See my thread on M5Board

http://www.m5board.com/vbulletin/e39-m5-e52-z8-dis...

I think by concensus it's likely to be driveshaft bearing - my car is going in for some work at my indy next week when hopefully when it's up on a ramp and running we can identify where the noise is coming from.

See threads below identifying the same problem:

http://www.m5board.com/vbulletin/e39-m5-e52-z8-dis...

http://www.m5board.com/vbulletin/e39-m5-e52-z8-dis...

humpbackmaniac

Original Poster:

1,898 posts

265 months

Thursday 8th April 2010
quotequote all
Thansk Roan, will be happy if it is just the prop bearing. Can you post up how you get on?

humpbackmaniac

Original Poster:

1,898 posts

265 months

Monday 19th April 2010
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Hi Roan, did you get this sorted? Ic ant get in to your M5board link.

Mine is getting gradually worse and driving me mad.

Roan

527 posts

225 months

Monday 19th April 2010
quotequote all
The car's getting some work done at the moment. I had the gearbox oil changed out and my mechanic reported that it was a) black and b) had the consistency of water. He flushed out twice to make sure any bad oil was removed. There was a whine in lower gears which I hope is now greatly reduced as a result, but I don't believe this is the same noise which you are referring.

I also had the diff oil changed and the seals inspected. The driveshaft bearing was OK apparently, but one of my front wheel bearings was shot. I'm not sure this was the cause of the noise, but I'll be speaking to my mechanic this morning to find out a bit more. Incidentally, a new wheel bearing was £230 from BMW. I sourced one for £65 delivered (new with 12 months warranty) from Parts Gateway, although bmminiparts.co.uk were quoting £101 which wasn't bad.

humpbackmaniac

Original Poster:

1,898 posts

265 months

Monday 19th April 2010
quotequote all
Thats handy to know, thanks for keeping me in the loop. I will be replacing my "life time" oils next time she is on the ramp.

Let me know what changes you see. I just hope the Diff doesnt need to come out, for inconveniece as much as cost, cant be without her for too long at a time.


Roan

527 posts

225 months

Thursday 29th April 2010
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Well I got the car back last night with the gearbox oil changed, front and rear ARB bushes replaced and the right front wheel bearing replaced. The car was checked over pretty thoroughly and it appears that the diff wasn't leaking at all and the driveshaft bearing was OK too. My mechanic wasn't sure of the whine to which you and I both seem to be referring, but it is still there mad To be honest, I didn't emphasise enough that this was my major concern. The more I hear it though, the more I think it's a vacuum leak somewhere which only appears under load/part throttle.

To say it's frustrating is an understatement, as it's making me want to sell the car... frown


humpbackmaniac

Original Poster:

1,898 posts

265 months

Thursday 29th April 2010
quotequote all
Damn! I was relying on you!

Roan

527 posts

225 months

Thursday 29th April 2010
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Is it the same problem as mine though, i.e. only whining on part throttle? If not, I would suggest the prop bearing. I don't really have the time to take apart the intake manifold/plenum but I guess I'm going to have to. With the symptoms I have being related to throttle position I can't think what else it could be other than a vacuum leak.

humpbackmaniac

Original Poster:

1,898 posts

265 months

Thursday 29th April 2010
quotequote all
Mine is onl on part throttle maintaining speed rather than accelerating or decelerating. I am hoping Prop bearing too, will check next time she is up in the air.

roofer

5,136 posts

235 months

Thursday 29th April 2010
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Part throttle would make me suspect layshaft bearings.

Roan

527 posts

225 months

Thursday 29th April 2010
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roofer said:
Part throttle would make me suspect layshaft bearings.
The 'box whines a little in 1st, 2nd and 3rd (reduced a bit since the oil change - incidentally my mechanic tells me the old oil was akin to black coffee) but I suspect that whine is from slightly worn layshaft bearings rather than the whine to which the OP and I are referring. It only happens at 45mph+ and happens in any gear (3rd upwards) so I don't believe it is gearbox related.

I've never comes across a problem that can't be solved after half an hour's googling until this one... mad

Roan

527 posts

225 months

Thursday 29th April 2010
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I think I've got it. Crown/Ring & Pinion gear in the differential (google is in the end, your friend).

A 2nd hand diff is upwards of £450 so I'm interested to know how much labour is involved in swapping out the crown & pinions gears of the diff if I can source the parts...

M5Tom

345 posts

193 months

Friday 30th April 2010
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I think I saw a E39 M5 crown and pinion on ebay last night............

Roan

527 posts

225 months

Friday 30th April 2010
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M5Tom said:
I think I saw a E39 M5 crown and pinion on ebay last night............
Shhh..

CarbonBlackM5

3,078 posts

242 months

Tuesday 7th December 2010
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Roan

What happened, did the diff sort it out.

I have got a slight whine in 1st, 2nd and 3rd and a loud one at 70-90mph in 5th and 6th. I have put this down to the car having doen 172K of mainly motorway miles. It doesnt bother me and the diff has had new oil and seals but Im wandering where to start when I do want it sorting.

ArmaghMan

2,721 posts

204 months

Tuesday 7th December 2010
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humpbackmaniac said:
On a smooth road I get a slight whine when holding a constant speed, diff or prop bearing do we think? It is getting a little worse per 1k not enough to worry yet but annoying none the less. I dont think it can be a rear wheel bearing as it appears to be drive train stress related.


Or it could just be the fuel gauage dropping! smile Worth every penny though
sounds like the same problem I had
The grease in one of the transmission shaft joints was solid
try that?

CarbonM5

927 posts

215 months

Tuesday 7th December 2010
quotequote all
Mine had this,I thought it was the gearbox since it was really loud in 4th and 5th at around 50mph.

After I replaced the input seal at the front of the diff and retorqued the input flange the noise went away,replaced the oil and halfshaft seals aswell.