Rear Subframe Movement

[ashje]

So basically my subframe moves up and down a lot, when it's jacked up and axle stands placed under the rear subframe the subframe sits roughly half inch to an inch higher than when the wheels are on the floor.

Bushes are less than a 1000 miles old, I use the big subframe bolt to jack off and put stands under the subframe. I have read i should not be doing this but i absolutely hate jacking old cars off the sills!

My question is should there be this much up and down movement?

Thanks
Ash

[Topblag]

I'd be checking the top of the subframe bolt inside the car under the rear seat, check that the plates which tie the subframe bush into the cills are on correctly and lastly that the bottom nut from the subframe bolt is tight.

I tend to jack off the diff at the rear and place the stands on the subframe bush area.

The bush is there to make sure the beam can move in a controlled manner but that seems like excessive play to me.

[ashje]

Maybe i was over exaggerating with an inch but there's still quite a lot of up and down movement and the rear of the car feels loose when driving spiritedly!....almost like it's not connected properly.

I'll try and take some snaps of how it sits, i'm pretty sure all the movement is coming from the rubber bit of the bush.

[ashje]

[ashje]

To me it looks as if the bush isn't all the way in

[ChrisHC]

..I use the big subframe bolt to jack off...

Now I have spurted coffee all over the keyboard!

[DanThe]

You have pushed the beam off the bush by placing axle stands under the beam, this is the reason why you shouldnt be doing it. as said, jack under the diff, axle stands under the bolts

[ashje]

Right ok, but i shouldn't have caused any adverse affects by doing it this way and my nervous rear end is being caused by something else?

I'll do it that way from now on!

[paultv]

Is it wise to lift the rear using the diff case??

Paul

[Topblag]

Is it wise to lift the rear using the diff case??

Paul

As long as you don't do anything stupid, it'll do no harm.

To give a more extreme example, I jack up the rear of my 911 on the engine and thats the recommended way to do it.

Don't worry.

[Topblag]

Right ok, but i shouldn't have caused any adverse affects by doing it this way and my nervous rear end is being caused by something else?

I'll do it that way from now on!

What Dan said above.

I can't make out from the photos where the bush is seated but if the beam isn't tight with the bush in the right position, you'll have all sorts of problems. Car isn't safe to drive until it's resolved IMO.

RWD and no traction control with the most critical component for holding the rear suspension together not seated properly is literally an accident waiting to happen.

[Topblag]

I see it now, the bottom of the beam isn't connected to the chassis through the connector plate.

[Brianmoooore]

Although it's a good idea not to jack the beam as you have, with bushes in good order, no damage should be done.
What did you use as a lubricant when fitting the bushes? It MUST be a lubricant that ceases to be one shortly after fitting.

[BenHar]

I see it now, the bottom of the beam isn't connected to the chassis through the connector plate.

I agree it looks wrong to me.

Ben

[Brianmoooore]

I see it now, the bottom of the beam isn't connected to the chassis through the connector plate.

You mean the bolt doesn't go through the bottom plate, and the nut is above it ????

[ashje]

The big bolt goes through everything and the nut is underneath the black support plate thing, everything is tight.

The only issue i can make out is the beam moves up and down whilst the bush stays still, this only seams to happen when axel stands are placed on the beam, not sure if this would happen when driving too!

[biffer]

has inner part of bush been torn from outer

[Sanchez]

Which brand bushes?

[Topblag]

has inner part of bush been torn from outer

It's either that or the top of the bolt isn't where it should be.

[ashje]

I don't think it's torn itself in two and off the top of my head FEBI, i will double check the other end of the bolt tomorrow but i'm nearly 100% certain it's good.

I had someone else fit the bushes, so i'm not sure what was used and it was quite a while ago now, time wise not mileage!

It's as if the bush is loose in the subframe, i will have a better look tomorrow as it was getting dark this evening.

[milescook]

Doesn't seem from the pictures the bush is moving - No matter what lubricant you use that thing is tight as a gnat's chaff It doesn't *seem* to be the problem to me. More likely than that the core is detached from the rubber - but even then I'm sceptical.

As said though the bush definitely isn't on properly, I'm sorry but whoever put the bushes in needs to do them properly which may mean (unless they have the correct expensive tool) taking the beam off. See here:

http://cookracing.co.uk/index.php/e30-3 ... me-removal

There is no gap between the lib of the bush and the housing. If however you ever see the gap between the lip and the subframe move at all then Brian is right, those bushes need to come out and be put in properly.

Also, for reference (it likes look the bits are where they should be but still)

https://www.realoem.com/bmw/enUS/showpa ... Id=33_0211

Does the rear end feel loose, or about as compliant as a toddler? If there's excess movement in the rear beam it should be an utter pig to drive.