Knocking sound at rear of car 323i

[Tscotten]

My guesses:

Worst case first. Not likely, but depending on the history of the car, it could be the rear subframe ripping from the body. Flawed design especially in the early USA spec model E46's, not so much in the EURO spec models, but it does occur. Easy to spot if you have the car on a lift.

Easier guess is the wheel bearing, since the sound gets worse the faster you go. If indeed the knocking noise goes faster as you accelerate, then the bearing is worth a look. But the bearing should make the same noise below 60km/h too.

You are vague on the 'getting worse' part. If you mean louder, then have a look at the shocks and suspension. An out of balance tyre can also create unharmonious sounds with the suspension. Have a look at the shock mounts.

For all this you can go to a Speedy or Kwikfit that do a free check for faults. If you are unsure, get two or three different opinions or ask to have a fellow fanatic help you out in your area. :thumbsup:

OMG ..lets start with not worst case ...mm?...giehie...ok so long and short take it to a speedy or Hi q etc...i shall do so ...maar as hulle n gat in my kop praat ...i will be back...then maybe we can all go visit the "specialists" lmao.....and getting worse i mean louder....and i do not hear the sound below 60km....but i shall go ask ...and come tell u what the "experts" say...giehie

thanks guys ...MWAH ...TASH:wave:

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I with NicS, would guess shocks, shockmounts, might even be sideshafts.

ok so now i know what i should be looking at ...erm what the hell are side shafts? wait i will google that ...giehie....

GUESS WHAT I KNOW WHAT SIDESHAFTS ARE...AND MORE TO THE POINT I KNOW WHAT THEY LOOK LIKE.... AND DO!!!!!!HA HA HA HA HA :excited:

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ok ok OK....so tell me exactly what u meant by body ripping apart?!?!?!?!?1...cause i went to HI Q ..and my right back at the shock the body seems to have a tear in it....(thats the only way I can describe it ...a tear.....) :dropjaw:

so whats the best way to fix this ...erm can it be fixed?...cause in essence the shock is now not doing it work as its not got anything to support it...am i making any sense here?!?!?!?1

tash

 

[Sankekur]

I assume then that it is the back shock mount that is torn?

 

[Tscotten]

I assume then that it is the back shock mount that is torn?

erm ja that sounds like what it is ...( i think...) anyways best way to fix ...can it be fixed??:shocked:

 

[Sankekur]

Unless I am mistaken you can have it replaced.

 

[Tscotten]

Unless I am mistaken you can have it replaced.

Not sure if i explained it properly...ok its a tear in the physical body work of the vehicle at the right rear wheel and the shock is mounted to that part of the vehicles body.

HI Q says not an issue, weld the tear closed, and replace the shock as it has taken alot of damaged...

how would that affect the handling of the car, cause common sense tells me now there is a weakness on the body, my concern is the shock is mounted to that weakness....or am i smoking my socks?

and what could have caused it ?....any idea?

tash

 

[Jandre]

A good weld is extremely strong.

1 inch migweld( properly done), can lift 1 ton. (Thx Discovery )

A panelshop will be able to do that repair.

 

[Sankekur]

If something is welded it should just be properly sanded down and resprayed to prevent rusting as welds or at least the areas around welds have a tendency to rust.

 

[Tscotten]

:excited:

If something is welded it should just be properly sanded down and resprayed to prevent rusting as welds or at least the areas around welds have a tendency to rust.

:excited:...u see this place is the BOMB..thanks man guys now i am very happy...u are all so AWESOME....thanks man ..phew now i feel so much better.....i owe u guys BEEEGGGG time ,...thanks man MWAH!!!!!!!!!!!!!!!

 

[akash]

Hi Guys

I buddy of mine has a E46 325ci i think its 2002 model, he had a knocking sound coming from the left rear side of the car. He thought it was the diff. We had the car lifted up, the under carriage was ripped close to the rear left of the diff. This damaged the rubber bushers on a bracket that held up the diff (not sure if am explaining this properly). The ripped section was welded and problem solved.