Rear Suspension Mounting

[Grizzly]

Strewth. Just by chance, I happened to have the venerable Richard's Video Tape A playing this evening. There's a bolt going through the large rubber mounting bush on each side and then through the floor. This is the bit where apparently it needs one of Bill's custom washer jobbies (recently talked about) to provide more clearance and stop it grounding out. Anyway, I have that all in place, but the tape then goes on about an additional bolt next to it (where Richard drills a hole alongside, through two layers and the floor also and then chisels out one layer so as not to crush the large tube so that the bolt only fastens the upper layer. I DON'T have this bit!!! I guess I need it and that mine's no different than anybody else's in this respect?

[Guest TerryBarry]

Yes I fitted the extra bolt.

This is a positive fixture between the rear subframe and the chassis. The big bolt is only going through a metal bush in the flexible rubber mounting.

Here's a picture of mine before fitting, I cut the access hole using a small grinding wheel

[Grizzly]

OK - But I have to ask why?

Doesn't the additional bolt suppress the purpose of the rubber mounting bush?

... and is this why (in effect) Bill's custom washer does away with any potential for damping this 'sub-frame' to the chassis?

[Guest TerryBarry]

OK - But I have to ask why?

Doesn't the additional bolt suppress the purpose of the rubber mounting bush?

Yes it does, on the Sierra the entire rear subframe was isolated from the body by rubber mountings - the two at the front and the bonded rubber differential hanging bracket.

The diff is solidly fixed to the subframe by two through bolts. We have now mounted the back of the diff direct to the chassis and the rubber bushes are used for location and the extra bolt fixes this.

The diff' hanging bracket is bottom left in the attached picture

[Guest FIRSTBUILD]

even with the two bolts going direct to the chassssis and the rubber bushes I dont think its that much holding the car together - just image the braking forces on the de-dion and what about the hoods that have two hundred plus horsepower ! -- I was really suprised that it all relys on just 5 bolts !-- hope you havent bolted your seats in yet !!

 

Steve

[Grizzly]

hope you havent bolted your seats in yet !!

No, actually I have'nt got round to it just yet.

Mmmmm, More bolts and plates spring to mind. Although I'm not aware of anyone mentioning this before. What does the panel think?

[Guest TerryBarry]

even with the two bolts going direct to the chassssis and the rubber bushes I dont think its that much holding the car together

 

In addition the outer trailing arm pivot bolts mount through a lug on the chassis mounting plate

Can be seen on the attached photo ( highlighted by a white background)

[Guest turbo]

Although I'm not aware of anyone mentioning this before. What does the panel think?

as tricky says watch the videos several times

[Nigel Rogers]

Hi,

 

Ref What does the panel think.

 

Isn't there (if done the RHSC way) 8 attaching bolts. 2 on each "floor plate" = 4 + 1 in each trailing arm = 6 + 2 in the diff = 8?

 

Also, I think that no matter how many bolts you have, the transmission of the forces to the chassis is no better than the strength of the plate onto which you are bolting the axle assembly.

 

Not heard about anyone ripping out their axle because the installation is too weak, but I do like the method that Battery Bill and Colin Usher have adopted

 

Not done it though, I'm on a budget

 

Cheers

Nige

[Grim]

Also, I think that no matter how many bolts you have, the transmission of the forces to the chassis is no better than the strength of the plate onto which you are bolting the axle assembly.

 

Not heard about anyone ripping out their axle because the installation is too weak, but I do like the method that Battery Bill and Colin Usher have adopted

i had a problem on my car, which came with it when i bought it. The passenger side plate fatigued off, so it was only held on by the diff mounting and the driver's side plate. It coped rather well, i covered 2000 miles before i found it!

[Guest Battery Bill]

On our next two Hoods we are going to cut out the silly rubber bush altogether and weld a solid plate in instead.

[Dave R]

bill,

 

i removed my rubber mounts, and plated the hole

if i did it again i would weld a plate on the topside as well, (cant remember why i didnt)

it would give better bolt location, and also give the chance of squaring up and lessening the stress on the chassis plates, i think in standard form they get bent into shape with the tightening of the bolts

[Guest Battery Bill]

Dave

I think its only retained (in Richards instructions) for ease of assembly really. It is not serving any purpose because it is being bolted up solid So best to get rid.

We are going to weld plates top and bottom with a tube down the middle so when you tighten the bolts you don't distort it.

[Longboarder]

I did half of one job, plate welded over bottom of bush area but as the beam was on the car never got round to doing the top. Then added support to the lower end of the mounting bolt.

 

Nigel

[Guest chris brown]

What does the panel think?

As others have said the bolts through the rubber mounts are only used to locate the tube on the 2B and it then needs to be bolted down hard to the chassis. If I was to do another I would cut off the mounts altogether like someone who posted a photo on site a few week ago (I have just done a search but can’t find it) as it made a much neater job. The alternative is to do as RS says in the video but don’t just chisel the hole bigger as he did but use either a stepper or cone drill and fit a grommet. But in any case the tube does have to be bolted hard down.