front end noise i just cant pinpoint. - PeachParts Mercedes-Benz Forum

kmaysob · #1 12-12-2005, 11:50 AM

ok, it has had a pop since i got it. it "pops" when backing up, and when going forward after backing up. i just rebuilt most of the suspension, however i didnt replace a few things. i foolishly didnt change the lower control arm bushings when i had the springs off.

they look pretty worn but in not sure if that is causing the pop. i replaced the guide rod mounts with the ones off my old car that were less than a year old. but the bushings on the bearing bracket were not replaced. that could also be making the noise. i didnt replace the sway bar bushings, but i am gonna take care of that soon. i didnt replace the "torsion bar bushings" (the ones that mount the sway bar to the upper control arm because everywhere i have looked says out of stock. that and the lower control arm bushings are what i suspect most but i was hoping for some input from others. and input would be greatly appreciated.

dannym · #2 12-12-2005, 11:55 AM

These might help you out:

Front suspension rattle 300SD

my arse is draggin

danny

MikeTangas · #3 12-12-2005, 05:37 PM

Sounds an awful lot like guide rod mounts.

But, since you replaced them with used ones, I can't see how that could be

.

Take another look at the, uhm, guide rod mounts.

kmaysob · #4 12-12-2005, 11:35 PM

i was kinda thinkin that but um they were less than a year old because i installed them in the old car

wbain5280 · #5 12-13-2005, 12:12 AM

Be careful how you install them. Look at the link:

http://mb.braingears.com/126_DISC1/program/Chassis/33-615.pdf

and notice how the plastic hammer is used to install them. I used a 22mm open ended wrench on it's side and beat on that with a plastic hammer. Don't use a shop press to install them or in a year, you'll do it again. AMHIK.

If it's still popping, you need to check all things mechanical that move. Sound travels well through the steel chassis.

You might look at the u-joints, flex discs and center bearing, all drive shaft related.

kmaysob · #6 12-13-2005, 09:23 AM

Quote:

Originally Posted by wbain5280

Be careful how you install them. Look at the link:

http://mb.braingears.com/126_DISC1/program/Chassis/33-615.pdf

and notice how the plastic hammer is used to install them. I used a 22mm open ended wrench on it's side and beat on that with a plastic hammer. Don't use a shop press to install them or in a year, you'll do it again. AMHIK.

If it's still popping, you need to check all things mechanical that move. Sound travels well through the steel chassis.

You might look at the u-joints, flex discs and center bearing, all drive shaft related.

well i dont own a press nor do i know anyone that does so i used a deadblow hammer. thank you people who have tried to help. i appreciate it. im still kinda leanin towards the lca bushings, it doesnt make one solid pop like a guide rod mount does. it makes several when backing out of a parking space then several when pulling forward after reversing.i had the same problem on my old car even after i did the guide rod mounts, but i figured it would go away after i did the ball joints and all that stuff.

MikeTangas · #7 12-13-2005, 07:35 PM

Wasn't trying to pick on you...just bein' funny.

Anyway, I think it has something to do with the steel portion of the assembly compressing a little upon being installed the first time. Once popped out, when you try to reinstall them, perhaps in a different bearing bracket, I expect they didn't fit quite as tight. Result, now they 'thunk'. If you installed the complete bearing bracket from the donor car, with guide rod mounts unmolested, then it is most likely someplace else.

Better