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[mr singh]

iv got a weird noise coming from the engine area on my SB3. it starts at around 10 MPH but becomes more noticeable at 20 and increases in frequency as you get faster, it doesnt change when you press the clutch and i dont think that it changes when you blip the throttle when coasting. the only way i can describe it is that it sounds like when you put a playing card between the spokes of you push bike, BUT its intermittent.

it doesnt sound like a wheel bearing, i have had new front tires fitted about 3 weeks ago and had it detailed 2 weeks ago. iv checked to see if there is anything stuck in the tires and i cant seam to see anything.

it is booked in with Mercedes on monday, hopefully the driver that will be picking it up will hear the noise and tell the tech that is working on it

[CrazyG]

I presume that this only happens when the car is in motion and
is therefore not engine 'rev' related or you would have said so,
and on the info you have given it can only therefore be related
to a 'rotational' movement...from the wheels or that area.

I would suggest jacking up the car and spinning up each wheel in
turn to see if one can find where the noise is coming from and
then localising the cause of it.  If the car goes in to MB then
one hopes it'll be raised up on a hoist and that they'll find it.

[Deszus]

Check if wheels bolt/bolt nuts are tight.

[minimayhem]

I had this noise.

It was the differential, the planetary gear for the o/s/f was damaged.

I found this by jacking the car up and rotating the drive shaft for each side until the noise was heard.

Not saying yours is the same, but just letting you know what I found.

Oh just to add mine wasnt intermittent but was only noticeable when road noise was low.  Also when I cornered hard on the damaged side it was very audible.

[Problemchild]

brake line rubbing on the alloy spokes??

i've had this caused by me adjusting things

JJ

[mr singh]

Check if wheels bolt/bolt nuts are tight.

I fir the tyres at work and iv taken wheels off that many times that i have the habbit of torquing the wheel nuts, so the wheel nuts are tight.

brake line rubbing on the alloy spokes??

i've had this caused by me adjusting things

JJ

cant see it being the brake flexies as they are too far away from the wheel spokes. you do have wilwood brakes so in your case it may be plausible.

im at work tomorrow so i might have a quick look myself.

i have been playing about with the noise and i know its dangerous to switch the engine off whilst going down hill and the noise seams to be there. i have also noticed that there is a noise like gears rattling now and then. if the gear oil was low id notice drops of oil on the drive and its all clear.

[Deszus]

So top up some gearbox oil first.

If won't help, probably only gearbox rebuilt will help.

[Brabs]

One thing I would check is to have a peek under the front wheel arches and see if one of the headlamp bulb flaps in the plastic liner has dropped down. One of mine did once and was rubbing on the tyre. Just a thought. 

[mr singh]

So top up some gearbox oil first.

If won't help, probably only gearbox rebuilt will help.

its had 2 gear oil changes... once because i figured it best to do it and the 2nd a few thousand miles later when i replaced the clutch. and before you say it could be a possible clutch problem, the noise surely would have come sooner as i did the job back in november/december last year.

i used the genuine oil that Mercedes recommend from there parts department.

had it up on the ramp at work and it sounds like its definitely coming from the gearbox, ran the car up on the ramp and stopped 1 wheel at a time and the sound still was coming from the gearbox, so the headlight access panel can be ruled out.
i used my stethoscope to locate the noise and it made the same noise where ever i put it on the gearbox.

its off to Mercedes tomorrow, hopefully they will identify the noise and ill have to start saving for what ever the out come may be.

[Problemchild]

Could just be cv joint?

JJ

[mr singh]

if it was a CV joint, then the noise would have stopped on one side when i held 1 wheel whilst it was in gear on the ramp...

[mr singh]

went to Mercedes yesterday, they said that it was an exhaust heat shield that was catching and that was the reason i had that noise, £80 later and the car was delivered back... and guess what, the noise is still there. ill be popping back on saturday to speak to them.

[Problemchild]

and based on the wing mirror debacle you expected......??

JJ

[mr singh]

i expected nothing less... its a shame there isnt a specialist in Leeds.

i think Mitsubishi would have been more helpful!

[Deszus]

£80 for exhaust bracket? Must be a joke.

Remove gearbox and be ready to replace some bearings.
Mine works much quieter with 20mL of molybdenum disulfide. Old trick from middle of XX century.

Try if that will stop noise. If not, that gearbox is cooked nicely. 🚮