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rocksonrocks
07-10-2007, 01:39 PM
I've got a 325i 2004 with manual transmission. I've read alot about rear end clunks and thuds. My car has about 20000 miles. I just purchased from BMW dealer about a month ago. I think it's been doing this all along but it's very intermittent. With the clutch full down on level grade, and the car staionary, sometimes when I put the car in 1st or reverse, I get a mild "thud" from the back? It's heard but I don't really feel anything. Is this what everyone else is talking about? I find it strange because if the clutch is down, there should be no power going to the differential. Is this just the gears meshing? I can't believe diff bushings are worn already. Any opinions?

Thanks,

genuine669
07-10-2007, 05:22 PM
I have a 2004 325 as well and I am experiencing the same thing. I usually notice it when I am in first at about 4000 RPM and push the clutch in.

wdaveweaver
07-10-2007, 05:48 PM
2004 with 20K, should have a CPO and the original warranty left. Take it to your service advisor.

agaafear
07-10-2007, 06:03 PM
I have a 320i with 63,000 miles on the clock and my car does this. I have had previous 3 and 5 series cars and this cluck was there. It seems to be a feature of these cars and has never caused me any problems.

Fast Bob
07-10-2007, 06:19 PM
When you`re in gear and the trans is under load, everything inside is locked together....when you step on the clutch, especially at higher RPMs, you`re removing the load and everything goes into "free spin", where the gears are free to clunk against each other. Starting off in first or reverse, you`re just hearing everything lock up inside the trans.

Regards,
Bob

akhbhaat
07-10-2007, 07:16 PM
Starting off in first or reverse, you`re just hearing everything lock up inside the trans.+1

There are three basic "stages" in a manual transmission drivetrain: the engine, the transmission, and the driveshaft/differential/drive axle. The clutch controls the link between engine and transmission, and the shifter (via a piece known as the "dog collar") controls the link between drivetrain and transmission. As you can well imagine, the transmission is the intermediary stage between the engine and the physical drive components.

When you're putting the shifter into gear, you're essentially forcing everything in and between the transmission and differential/driveshaft to sync up. A mild thud is just an indication that some mechanical bits are shifting around to make this possible.

alpinewhite325i
07-10-2007, 07:27 PM
Mine does it occasionally.

Bottom line is don't worry about it.

Ricky318i
07-10-2007, 11:37 PM
thanks alpinewhite .. I feel more at rest now:)

rocksonrocks
07-11-2007, 11:24 AM
Thanks for all the feedback. The car is CPO but I don't feel like wasting my time on something that I thought might be normal. I'll either try to test drive another one or just wait. My warranty expires in April 2010.

EddieB
07-11-2007, 07:18 PM
I had a 2002 325i which would give a mild thud once in a while, but you ain't heard nothing compared to an M3--which is quite normal I'm told.

acidragon
08-03-2007, 10:35 AM
I have 2004 325xi manual, I have these problems too... Ive taken it to the dealer and he couldnt even figure it out. He gave me run around answers and told me not to worry about it. (bmw of manhattan no less)

1. Sometimes going into first ill hear a thud under the car and the shifter will go into gear with no problems. (usually if im just moving just a very very very slight tad)

2. If im in traffic and engage first gear but have to stop due to traffic ill hear metal clank. But i think its because the rpms were on their way up and i release the pressure and everythign goes spinning. If i give the car time to eat teh power of the engine it wont make the noise.

3. At stand stills sometimes i have problems getting into first gear. Took it to the shop also for this but tehy said my forks are straight and he wouldnt know why that would happen. sometimes other gears get stuck. I shift very calm and nice so i woudlnt know why it would get stuck

Also Does anyone else hear a bang in the middle of the car on the underside when shifting? I know its because the rpms dont match when the gears are changed but its only like a 200 rpm difference and it will make a loud and noticeable clank.

Vampo
08-04-2007, 12:36 AM
I get this thud when enter the gears, and also a louder thud when releasing the clutch on the first and reverse.

I even got this noise when changing gears from 3rd to 4th and I'm convinced that it the differential. Pls let me know if you find the cause.. It's really annoying...

Thanks
Vam

agaafear
08-05-2007, 05:15 AM
3. At stand stills sometimes i have problems getting into first gear. Took it to the shop also for this but tehy said my forks are straight and he wouldnt know why that would happen. sometimes other gears get stuck. I shift very calm and nice so i woudlnt know why it would get stuck


This happens in my car also and it has also been a feature of previous 3 series cars I have owned. If 1st wont engage easily, then I slide it into 2nd and then into 1st without a problem!

akhbhaat
08-05-2007, 12:19 PM
3. At stand stills sometimes i have problems getting into first gear. Took it to the shop also for this but tehy said my forks are straight and he wouldnt know why that would happen. sometimes other gears get stuck. I shift very calm and nice so i woudlnt know why it would get stuck


This happens in my car also and it has also been a feature of previous 3 series cars I have owned. If 1st wont engage easily, then I slide it into 2nd and then into 1st without a problem!This is normal.

Another trick you can try is to let the car roll forward or backward a bit (if you're on an incline) before engaging first.

acidragon
08-06-2007, 06:08 AM
yeah soemtimes at teh traffic light when i t wont go into first ill just start in second or use second to roll a little then it will go into first easily. anyone else have any of the other problems?