E46 rumble noise

[OctaneV8]

Went to look at an E46 auto today, engine sounded fine and autobox was smooth, here was a mild hiss / turbine-like noise pulling away but no nasty clunks, however I could detect a constant rumbling noise.

I popped the autbox into neutral going down a hill and there was no change coasting along.

From the driver's seat I couldn't feel vibration around the transmission tunnel, so am guessing it could be the diff? The seller mentioned something about diff bearings might need replacing. Any ideas on what it could be and the cost to fix?



Cheers


P.S. I drove there and back in another E46 auto (my 2002) and driving this car I can feel a vibrating prop through the trans tunnel, but unlike the car I viewed there is a distinct lack of rumbling which is why it agrees with the seller's impression than it was the diff.

Edited by OctaneV8 on Friday 5th July 08:17

[helix402]

Prop coupling and or prop centre bearing worn are more likely causes than the diff.

[d_a_n1979]

helix402 said:

Prop coupling and or prop centre bearing worn are more likely causes than the diff.

This...

If it were the diff, you’d really hear it but not necessarily feel it...

Get the donut and prop bearing checked over first; my £££ being on the donut gone

[OctaneV8]

I couldn't feel any vibration at all, but I could really hear a constant rumbling, not a pleasant noise that I could put up with on more than a 10 min journey.

I can't really get it checked over properly unless I liase with the seller somehow to get it into a BMW indy garage local to him.

Any idea how much £ the prop bearing would be vs. the diff or driveshafts?

d_a_n1979 said:

This...

If it were the diff, you’d really hear it but not necessarily feel it...

Get the donut and prop bearing checked over first; my £££ being on the donut gone

[helix402]

OctaneV8 said:

Febi prop coupling is around £50, centre bearing £35. Used diffs vary, normally £150 ish.

[naturalaspiration]

It could also be a worn wheel bearing especially if there is a change in rumble tune when turning.

[Sardonicus]

If its an E46 2.5 M54 your looking at I have a perfect prop-shaft complete with new Febi/Bilstein centre bearing and an auto diff faultless no noise and recent service before changing to a lower ratio unit ... if the issue is either ....just saying

[OctaneV8]

Thanks for your offer!

I went to look at a 330d today, it felt smooth no major issues or funny noises but it did feel a bit slow to pick up speed, compared to the 320d which has more get up and go (throttle response and turbo feel eager). What could be wrong with the 330d?

[helix402]

Not meaning to be rude, but the E46 is an old car now. A good 3.0 petrol or diesel (or 2.8/2.5) is a great car-but they need to be in good condition.

If you’re not able to fix it yourself it can quickly become an expensive car to keep going.

Re 330d feeling slower than a 320d-there’s a problem!

Could be numerous things, eg:

Faulty turbo, turbo pressure converter, boost hoses, vacuum hoses, intercooler, air mass meter, dirty air filter, ecu not programmed for new air mass meter, etc........

[OctaneV8]

Thanks, not taken as rude at all! I enjoy fixing cars, and just looking for a second car I can throw a bicycle in the back of that handles reasonably well and is comfortable long distance. I have become accustomed with BMW and the 320d was a project.

When I tried the 330d I forgot to unplug the MAF and check the vac hoses. It did feel much more nose heavy than the 320d and the steering was much lighter, easier but felt a bit odd.


What car would you recommend on a low budget 1-3k?

[helix402]

OctaneV8 said:

Thanks, not taken as rude at all! I enjoy fixing cars, and just looking for a second car I can throw a bicycle in the back of that handles reasonably well and is comfortable long distance. I have become accustomed with BMW and the 320d was a project.

When I tried the 330d I forgot to unplug the MAF and check the vac hoses. It did feel much more nose heavy than the 320d and the steering was much lighter, easier but felt a bit odd.


What car would you recommend on a low budget 1-3k?

I’d go for a 330d. I’ve had two and each has had a thread which covers most of the common problems and how to fix them.