Clattery G Box rumble on W124 5Sp Man Box on T/O

[isobars]

Hi All,
I'm not actually sure of the gearbox number, but it's a five speed manual on an 89 300E, W124, 140k miles.
Gear selection is smooth except in reverse when the engine is hot, then, there's a grinding going into reverse.
Putting it into a synco gear first stops the grinding.
At full running temerature only at tick-over there's also what I'd describe as a clanky sound from around the gearbox area.
Depressing the clutch pedal makes the noise go away immediately.
Any ideas/thoughts gratefully received!
Cheers,
Paul

 

[carat 3.6]

That sounds like the gearbox input shaft bearings.

 

[isobars]

Ah!

Clutching at straws here, if it only makes a noise when very hot, could it be short of oil?

Thanks for your response.

Cheers,

Paul

 

[carat 3.6]

I doubt it, but easy to check.

If I was in your position, I'd take the gearbox off to inspect the clutch and release bearing. If those are ok, fill the gearbox with royal purple syncromax and cross your fingers....

 

[WDB124066]

Syncro hubs dancing?? If you gently move the shifter to select a gear without depressing the clutch with Engine running will that lessen the noise....?

 

[bolide]

That sounds like the gearbox input shaft bearings.

Or a knackered release bearing?

Nick Froome

 

[isobars]

Syncro hubs dancing?? If you gently move the shifter to select a gear without depressing the clutch with Engine running will that lessen the noise....?

Yes!!

Just the merest touch toward first and the Rhumba stopped immediately.
The car has been stood for many years, could this be a factor?
The noise is not there when cold.
More straw clutching than de-clutching here.

Many Thanks for everyone's input.

Cheers,

Paul

 

[WDB124066]

When the oil is cold it prevents the chatter, if this is all it is learn to enjoy it or maybe try another oil. Maybe Mercedes already know a quieter oil for it as yours wont be the only one doing it...??

Alternatively new bearings, syncro hubs, clutch and hydraulics etc...