M3 Gearbox

[benadams]

Hello...

I have a 2001 Y Reg M3 with a manual gear box. I havent had it very long and i have noticed that its slightly difficult to get into gear. It goes in fine and it doesnt crunch but you have to use a bit of effort to get it in and somtimes there is a faint clunk/crunch type sound. Its only really with 1st, 2nd and 3rd that it happens. The clutch seems fine and isnt loose so to speak at all.

Is this normal for an M3 or is there something a miss?

Thanks

Ben

[M3John]

Sound s a bit spooky to me mate this one. I'd suggest giving your local indipendents a call and see what they've got to say. Don't quote me here but sounds like a linkage problem.


M3J.

[benadams]

OK - Will Do. Does anybody know of any good BMW idie's around the Milton Keynes area?

[Dave Dax builder]

Thorney motorsport.

[benadams]

Thanks - i've just dropped them an email!

[M3John]

Dave Dax builder said:

Thorney motorsport.

These are top blokes in the business mate. I'd suggest dropping them a call. Be sure to let us all know how you get on.

M3J.

[anwp]

My be I can help.

I have just had the gearbox, clutch and flywheel all replaced on my 2001 M3, because of a slight baulking effect when selecting 3rd gear. All done under warranty. However the problem has'nt really gone away completely and I believe its the diff sending blacklash shocks through the layshaft in the gearbox. it only does it when driving slowly in traffic.

As well as replacing the gearbox, clutch and flywheel I had the prop-shaft drive rubber replaced and the prop-shaft and support bearing checked. So the only thing left is the diff.

Do you get a drive line "clunk" if you let the car idle out of gear with the clutch up and then quickly clutch down and select 1st straight afterwards?

[benadams]

well i really hope i dont need all of that work done as my car isnt under warrenty!

Theres a slight clunk when changing in 1/2/3 The gears dont just slide in - you have to use a fair bit of force - well not force but you know what i mean. It just feels like the cogs arent slotting into place with 100% accuracy or that its objecting in some way to going into gear easily!

[anwp]

Thats the same as I had and still have for that matter.

Try the test I mentioned in the previous post. I know its not the gearbox its the diff. However trying to get a new diff out of BMW is almost impossible as they state thats its acceptable (£1500 plus fitting.

I just live with it. It has been the same for 25,000 miles so I doubt it will get any worse.

[Fixedwheelnut]

The excess freeplay in an M3 diff is designed in to allow for expansion when they get hot when they are driven hard, the unfortunate side effect is a slight clonking when changing load whilst it is cold.

Edit to add, if and when the box is out make sure they clean the splines on the input shaft as a popular cause of juddering is the clutch plate not disengaging fully because it sticks on the splines.

Edited by Fixedwheelnut on Friday 16th March 23:07

[mpowermark]

Like someone said earlier, sounds to me like you may have a linkage problem. Do you change gears quite aggressivly?

[benadams]

no not at all. I try to change as smoothly as possible. I cant guarentee how the previous owner treated it though

[brenmona]

Could it be the clutch? I know on Z3Ms there are sometimes problems getting it into first, an by changing the hose to Stainless steel braided type it solves the problem, Its a cheap fix £30 ish

[ianm3]

Mine is also a Y reg manual (83k) and i drive it hard. I have a similar issue but mainly when its cold or i'm in traffic. At speeds the change is spot on.

I think to echo some of the comments above, its a common thing and not to be too concerned about. The diff makes wierd and wonderful noises on both old and new cars

One thing i have noticed of late in mine is that when in gear i can rattle the gearstick from side to side, i dont remember being able to do this before?