View Full Version : Transmission "clunk"
Yesterday morning... started car for commute.... put it in reverse [confirmed by right mirror adjusting down]...
As I started to back up, there was a loud "clunk" from what seemed under the car... almost sounded/felt like I ran over something on the freeway.
Got out... no leaks... car shifts smoothly... made sure to check my path to confirm I did not run over anything....
Any thoughts? Do I have a funky transmission?
WOLFN8TR
10-30-2012, 07:10 AM
How many miles do you have on your ZHP? Auto or Manual?
nike001
10-30-2012, 07:34 AM
If it ain't broke don't fix it
True dat.
I just don't know if its broke..... That sound/thud was alarming. Something must have caused it.
JKO_ZHP
10-30-2012, 10:55 AM
If it ain't broke don't fix it
I disagree. Preventive maintenance has gotten me a long way, fixing things that look like they're going to give way any day ensures that it won't possibly lead to other problems should you leave it until it is broken.
Just my two cents.
I disagree. Preventive maintenance has gotten me a long way, fixing things that look like they're going to give way any day ensures that it won't possibly lead to other problems should you leave it until it is broken.
Just my two cents.
I agree as well.... and that sound was a result, a reaction.
I'm just trying to figure out to what....
Anybody???
nike001
10-30-2012, 01:02 PM
I disagree. Preventive maintenance has gotten me a long way, fixing things that look like they're going to give way any day ensures that it won't possibly lead to other problems should you leave it until it is broken.
Just my two cents.
How can you do preventative maintenance to a transmission? Replace it? Some techs will argue that changing the fluid is even a step backwards.
toddness
10-30-2012, 01:28 PM
Some questions which answers may provide more clues...
Were you parked facing down a hill?
When was the parking brake dis-engaged?
Was the car in a different gear before going into reverse?
Did you start the car before shifting into reverse or with it in reverse?
Did the sound come from the center or more towards the rear?
This mind wants to know...
Some questions which answers may provide more clues...
Were you parked facing down a hill?
When was the parking brake dis-engaged?
Was the car in a different gear before going into reverse?
Did you start the car before shifting into reverse or with it in reverse?
Did the sound come from the center or more towards the rear?
This mind wants to know...
at last...
My driveway slopes slightly, but I was backing out/rear facing down.
The parking brake was disengaged after after starting the car, before shifting into reverse [standard procedure for me].
The car was in N... I leave it in 1 to park, then shift to N to allow to warm up for a second or so.
I started before shifting into R
Good question... I'd say center if I am remembering correctly. I want to say say left side as well, but that my just be because I was on the left/driver's side.
It felt like a large "thump"... I have felt/heard a similar sound in other cars if I ran over something at freeway speeds..
thanx
webster
10-30-2012, 02:09 PM
when was the last time you flushed your diff fluid?
zj96sc
10-30-2012, 02:22 PM
I'll postulate guibo or u-joints. Can you recreate if you place alternate load on the drivetrain - namely fwd to rev or rev to fwd?
when was the last time you flushed your diff fluid?
a month or so ago
I'll postulate guibo or u-joints. Can you recreate if you place alternate load on the drivetrain - namely fwd to rev or rev to fwd?
I have not been able to recreate it, thankfully.
This is a manual, so I am not sure what you mean by "FWD"
danewilson77
10-30-2012, 02:35 PM
I have not been able to recreate it, thankfully.
This is a manual, so I am not sure what you mean by "FWD"
It's fixed! Sweet!
Sent from Williamsburg, VA USA
toddness
10-30-2012, 02:46 PM
It's fixed! Sweet!
:biggrin
My money would have been on the guibo..
It's fixed! Sweet!
Sent from Williamsburg, VA USA
yeah.......
not sure I can determine if it's "fixed"... since I do not know what it was.
I thought someone here could help analyze... was hoping maybe someone would have had the same problem.
I don't know much about auto mechanics... but I know enough about machines to know that this type of noise is not common, and not reflective of a "corrected system". Things don't whack into each other like that unless something has "gone wrong"...
If something broke off, for example, it wouldn't keep making the same noise, since it would no longer be there to make said noise.
At any rate, thanx to those of you that tried to help :)
JKO_ZHP
10-30-2012, 03:04 PM
How can you do preventative maintenance to a transmission? Replace it? Some techs will argue that changing the fluid is even a step backwards.
Back when I had a 325Ci I remember being advised by a BMW tech (or at least he worked at the dealership) to have the transmission fluid flushed. Forgot what the problem I had was but I do remember that he said even if I don't have it done at a dealership, it's best to have it done and it is good unless your -something- has a lot of holes, then that's the only time when it might not be a good idea because it may expose those holes/cracks that were maybe sealed up previously by gunk I'm guessing.
danewilson77
10-30-2012, 03:47 PM
yeah.......
not sure I can determine if it's "fixed"... since I do not know what it was.
I thought someone here could help analyze... was hoping maybe someone would have had the same problem.
I don't know much about auto mechanics... but I know enough about machines to know that this type of noise is not common, and not reflective of a "corrected system". Things don't whack into each other like that unless something has "gone wrong"...
If something broke off, for example, it wouldn't keep making the same noise, since it would no longer be there to make said noise.
At any rate, thanx to those of you that tried to help :)
Just keep an eye on it....and let us know if it comes back. We'll put our thinking caps back on if it does.
zj96sc
10-30-2012, 07:38 PM
I have not been able to recreate it, thankfully.
This is a manual, so I am not sure what you mean by "FWD"
i mean a gear that makes the car go forward. something that will load the driveshaft in the opposite direction. i've had bad u-joints that lead to clunking under reversing after using a forward gear, or returning to a forward gear after reversing.
i mean a gear that makes the car go forward. something that will load the driveshaft in the opposite direction. i've had bad u-joints that lead to clunking under reversing after using a forward gear, or returning to a forward gear after reversing.
Oh, ok.
I'll try that tomorrow.
Though today no noise/clunk. I went from reverse to 1st at least two times... Nothing.
Am I misunderstanding you?
zj96sc
10-30-2012, 08:00 PM
No i'm sure you get what I'm saying and that probably isn't the issue. The idea is you want to load the u-joints in the driveshaft with opposing torque to see if the needle bearings went bad and that's where your clunk is coming from.
if you've cycling from f/r and r/f and it didn't recreate, that's probably not it.
Powered by vBulletin® Version 4.2.2 Copyright © 2024 vBulletin Solutions, Inc. All rights reserved.