Astra Front Sub Frame Mount

Hi there

While checking the brake pads etc on the front of my car today, I noticed
that the front subframe mountings on either side of the car looked a little
odd - to me, at least.

There seems to be a gap of around 2 - 3 mm between the head of the bolt and
the bush, and I wondered if this was normal, or whether it would explain the
odd noise I get when going over speed bumps etc from time to time (and which
my VX dealer has been unable to trace)

Any knowledgeable people out there who could comment, or perhaps people with
similar cars could look, and let me know if theirs is the same (but without
any metallic rattling going over bumps!)

NB users in this NG have advised in the past that a front spring may have
broken, just the end bit, but the springs are quite intact

The car is a 2002 Astra Estate 1.6 8-valve.

I've popped links to a couple of photos to try and illustrate what I mean.

The head of the mounting bolt is in the red rectangle - as you can see there
is a gap between the bush, and the head of the bolt of about 2 - 3 mm. In
each piccy the car is jacked-up using sill jacking point on the particular
side of the car, the other side of the car is not jacked-up i.e. is
supported on the roadwheel and suspension unit. The mounting bolts do not
feel loose.

A picture of the offside mounting is here:
www.murphy9100.fsnet.co.uk/CarStuff/OffSideSubFrame.JPG


A picture of the nearside mounting is here
www.murphy9100.fsnet.co.uk/CarStuff/NearsideSubframe.JPG

 

Got to ask an obvious question here, but have you tried tightening them?

Mike

 

yup

 

Oh well, I've got nothing else.

hang on, I can feel another slightly relevant but ever so boring memory
coming back to me.

In my more foolish days I used to have a rover sd1 2300 with a 4 speed
manual box. First time under I noticed a loose looking bolt protruding from
the bottom of the gearbox and passing through the small crossmember that
held the gearbox mounts. thinking it was loose i tightened it up. soon after
I took the car for a spin but didnt go far as there was a godawful rumbling
coming from the car. the bolt was a stop to limit upward travel of the box,
and when i tightened it all the transmission noises were transmitted to the
body, bypassing the mounting rubbers!

Moral:it might not need tightening (anymore)

Mike

 

The bolt mounts hard against the centre of the bush and the subframe is
mounted to the outside of the bush and this keeps them apart so vibration
isn't transmitted into the car. It's fine.

 

A picture of the offside mounting is here:

I would be more worried about the rust on the subframe! Give it another 2
years .....

I find it interesting that bodywork rarely rusts nowadays, but (Vauxhall)
subframes are poorly protected. Easier to replace than sheet metal, but it
will be expensive. Built in obsolescence is still around :-(

 

It's mud!

A good slosh with Waxoil come the spring is one the cards none-the-less,
thanks for the tip.