Intermittent Knocking - Passenger rear (ish)

[phil1066]

Brief history - did a nice long drive last weekend, mostly motorway, noticed when breaking sharply towards the end of the trip that there was a knock/clang noise from the rear passenger side. Never heard this before and I had driven on some nice twisties to feel the handling.

Anyway, on the last roundabout before home it did the same. I then jumped on here, found various threads marked subframe bolt etc, then got under the car and checked. The passenger side would only tighten a fraction and the drivers side turned a couple of cranks.

So I thought all good, took the car for a roundabout session and heard nothing.

Then as I was driving today I drove up a steepish offcamber slope and heard the noise again.

So Im back on here for suggestions and help please btw its a 2004 Phase 2

one question - when tightening the subframe bolt on each side was the car supposed to be standing on all four wheels or does it require use of a jack etc? not sure.

 

[blakey]

Subframe bolts will need to be torqued to the correct setting.

Not sure of the setting, im sure someone will advise. It would not matter if the car was jacked up or not, but if the weight is on the subframe (ie not jacked) it would help.

It would be benificial if the car was on a 2 post lift to get a good inspection. if only to be sure what is making the noise.

Note; if the subframe has moved a wheel alignment check should be done.

 

[pturner3]

Did you tighten all the bolts? There are more than two!

 

[Jamesv6]

 

[blakey]

9 daNm = 90 Nm

 

[phil1066]

More than two bolts? The article I found on this site only showed a pic of one. Does anyone have a diagram of the location for the others (that may sound a bit dim, but initially I thought the McSuspension was the subframe and tried to tighten those, but they require a special star fitting socket and I didnt have one).

thanks guys

 

[Jamesv6]

LINK Section 33-8 gives a rough idea where bolts are located. These bolts were briefly pointed out when I was underneath my Vee, I'm sure he pointed to at least 4 corners.

 

[phil1066]

thanks will have a looksee

 

[phil1066]

according to the diagram in 33-7 the two bolts I tightened were the front ones - if the arrows are correct there are two more back near the muffler - is this correct?

 

[pturner3]

Phil, there are four bolts, one in each corner (roughly). Have a good look around and you will find them.

 

[k1ano]

More than two bolts? The article I found on this site only showed a pic of one. Does anyone have a diagram of the location for the others (that may sound a bit dim, but initially I thought the McSuspension was the subframe and tried to tighten those, but they require a special star fitting socket and I didnt have one).

thanks guys

Yes the article (if it's mine you are referring too) only shows one bolt as that was the one loose on my car. It was annoying me for a while as a knock going over road bumps, I was also experiencing VERY perculiar handling ... It was hard to find the issue as I obvioysly tried jacking the car using the subframe so the loose bolt did not show, neither did it show on a four wheel ramp when I had the tracking done to try and fix the handling. Eventually I jacked the car up using the sill jacking points and used a rubber mallet and clouted various parts of the subframe and drive-chain and found a gap of a couple of mm at the front edge of the sub-frame and the rest is history - handling restored, knocking solved ... In my case anyway ...

As more and more cars are having their cam-belts done then this may be something for people to check as sometimes the engine is dropped out on the sub-frame so obviously the bolts have to be undone. Having said that, there is more chance they are re-torqued correctly in re-assembly I guess ...

Martin

 

[phil1066]

Found the other two bolts - they were tight - so not sure. Havent heard it since

 

[Ben123]

Digging this up again, but I finally got mine sorted. OMG, what a difference it makes!!! K1ano is totally right in the perculiar handling. I think mine must have been loose (but not so loose that it was making the clunking noise) ever since I picked up the car.

Now it's tightened, the car feels totally different powering out of the bends...different as in 10x better!!

So, worth checking this out, no question. It does seem to be the Right Hand forward bolt which is susceptible to coming loose. I had maybe 2-3 mm of travel.

Ben

 

[k1ano]

Digging this up again, but I finally got mine sorted. OMG, what a difference it makes!!! K1ano is totally right in the perculiar handling. I think mine must have been loose (but not so loose that it was making the clunking noise) ever since I picked up the car.

Now it's tightened, the car feels totally different powering out of the bends...different as in 10x better!!

So, worth checking this out, no question. It does seem to be the Right Hand forward bolt which is susceptible to coming loose. I had maybe 2-3 mm of travel.

Ben

Absolutely right Ben, transformed the cars handling from UNPREDICTABLE/DANGEROUS to AMAZING in one twist of the torque wrench :race:

Martin

 

[ravydavy]

Bumpy.

I've got a knocking from the rear which I want to sort. Had the car on axle stands last night and the subframe bolts wouldn't budge.

Am I right in thinking there will be less stress on them if the car was on a lift? I.E on the wheels? Therefore meaning they would be easier to tighten if they were loose?

Can't work it out. :tumble:

 

[johnler]

Wheels off the ground would be less stress