Noise. Need Opinion

[deano27]

Hey Guys,

I've got a manual r34.

I notice this noise mostly when I am reversing, let's say I am reversing and then i put the clutch down I can kind of hear a little clunk sound.

Not very loud, but loud enough to hear especially when the window is down.

Anyone have any idea?

Thanks

[HtwCHACtkh]

AFAIK it's normal. I hear it in almost all cars I drive.

You could try changing the transmission oil, I don't know if it would help tho.

[liampire]

Hi, here is some useful information about noises that I found a on a website: http://www.aa1car.com/library/2004/ic20428.htm

MANUAL TRANSMISSION DIAGNOSIS

People buy vehicles with manual transmissions for several reasons, one being that a manual transmission often comes standard and costs less than an automatic. Manuals are also more durable than automatics and make sense for drivers who put a lot of miles on a vehicle or plan to keep it a long time. And they are just fun to drive: Manuals give the driver more control over the drivetrain and the engine's power output to the wheels. But they can also be very tiring to drive in heavy stop-and-go traffic.

Consequently, most manual transmission problems fall into one of three areas: Clutch related (worn or slipping clutch); clutch or shift linkage problems (leaky slave or master hydraulic cylinder, broken or misadjusted cables, worn release bearing, etc.); or the gear box itself (bad synchronizers, noisy, worn or broken gears, worn bearings, bent or broken shift forks, pops out of gear, and so on).

If the transmission seems to be making noise, don't assume the problem is a bad transmission. A lot of things can produce noise that may sound like it is coming from the transmission. This includes worn CV joints, loose or broken motor mounts, and flywheel or clutch problems. A test drive will confirm the complaint and help you diagnose what might be causing the noise.

If the noise is only noticeable at idle, does it change when the clutch pedal is depressed? A change would probably indicate a problem with the release bearing or pilot bearing. To find out what is causing the noise, set the parking brake, place the vehicle in neutral and start the engine.

If you hear growling or grinding noises when the clutch is engaged, the cause is the transmission input shaft bearing.

A squealing sound that occurs when the clutch pedal is depressed and held is usually caused by a bad pilot bearing or bushing.

A chirping noise that intensifies when the pedal is slowly depressed would indicate a bad release bearing.

If you hear chirping while idling in neutral and the noise goes away when the pedal is slowly depressed, the fork/pivot ball contact point is making the noise.

Tip: On some BMW M3 models, what sounds like transmission noise at idle is often caused by a bad dual mass flywheel. Replacing the flywheel usually cures this problem.

Noise that occurs only while driving or in a certain gear usually indicates a gear or bearing problem inside the transmission.

If a particular gear grinds when shifting, that gear's synchronizer is probably damaged and needs to be replaced.

If all the gears grind or clash when shifting, the clutch may be dragging or not fully releasing when the clutch pedal is depressed.

Gear noise in all gears at all speeds may be the result of worn shaft bearings, thrust washers or gears, or a low lubricant level in the gear box (check the level).

A transmission that is stuck in gear can be caused by a bent shift linkage, broken shift cable, a shift rail or interlock failure, or a broken gear inside the transmission.

A transmission that jumps out of gear may be due to bent, binding or loose shift linkage, a loose transmission or clutch housing, worn or damaged input shaft bearings, broken motor mount, worn tapered gear teeth or synchronizer hub splines, loose shifter fork or rails, interlock hardware that is broken or missing, or excessive end play or runout in the output shaft or countergear.

If nothing happens when the transmission is put into any gear, the clutch may not be engaging, a CV joint or U-joint may be broken, or the main drive gear or countergear is stripped.