front sub frame bushes

[badger]

hi guys
i need to replace the front sub frame bushes and figured out that it would be best to do all 4, can these be changed without removing the subframe or is it a complete drop down job it's only these and the brakes to sort before we are back to being road worthy.

[cass3958]

The subframe bushes can be changed with the subframe still under the car. You will have to drop it enough to remove the old ones but you do not need to disconnect the steering, or brakes to get to them. The anti roll bar will need to be disconnected at the points where the bushes are bolted to the chassis rails so you might as well change the anti roll bar bushes whilst you are there.
There are four subframe bushes as you probably know two at the front which are the easy ones to get to and then the two side. The two at the side are held in place with a single bolt through the chassis leg.
When changing them I would leave the wheels on the subframe but make sure they are chocked to stop them rolling. I would remove the anti roll bush bolts and drop it down. Next undo the front mounts, if you can lower these down by leaving the wheels on the ground but jack the body up you should be able to remove the old ones and replace them with new but do not tighten them up leaving room for the bush to move. Next remove the single bolts holding the rear mounts to the chassis leg and the two nuts holding them to the subframe. Do the same leaving the wheels on the floor and lift the body up off the mounts. Remove and replace the mounts then lower the body back on to the mounts and replace the bolts. If you find the wheels are in the way jack the car up and support the subframe on axle stands. Remove the front wheels. When removing the subframe mounts leave the subframe on the axle stands and jack the body/engine up off the subframe. On my 1968 S Type the subframe is not connected to the engine as the engine mounts are attached to the chassis legs but some of the earlier cars had extra stabilizing engine mounts which I think were attached to the subframe. These would have to be removed.
You only need a small amount of room perhaps three inches to remove the rear mounts and there should be enough length in the flexi brake pipes, power steering pipes and lower steering column to allow you to do this.

[JCS]

Beware that the front sub-frame, rear mountings are handed. You will find that the two mounting studs are offset to one end, and they can be fitted wrong.

First paint mark your original mountings at the front or rear end for identification and then mark up your new units to suit.

[cass3958]

Beware that the front sub-frame, rear mountings are handed. You will find that the two mounting studs are offset to one end, and they can be fitted wrong.

I am glad you brought that up as I had forgotten and when I first fitted mine I put them on the wrong sides and then could not understand why I could not get the bolt on the front mounts. The subframe was back by about half an inch and I could not get the nut on the through bolt. Looking at the mounts it is hard to see a difference unless you know.

[RollyTG]

Hi gentlemen. I am almost done replacing my subframe and sway bar bushes. I am having a little trouble realigning the rear bushes as they are about a quarter inch too far forward. I don't think the problem is the "handedness" of the bushes because I put them back the way they were - ie with the flat end to the rear and the rounded end to the front. All information I have says that is correct. Hopefully you guys can point me in the right direction on this. Both bushes were completely separated and the sway bar bushes were pieces of radiator hose.

[cass3958]

Without being there to look at it , it is very hard to suggest anything other than turning the bushes around to see if they do fit. With new reproduction parts the manufacturers might have the round end flat ends the wrong way round. From my experience I put the rear mounts on first and found the fronts would not line up. I then turned the rear bushes 180 degrees and everything went together perfectly. If you look at the bush from the side when it is in your hand you can see that the threaded bolts are set closer to one end than the other so this is all I can suggest.

[RollyTG]

Thanks Rob. I have managed to get the sub-frame mountings all in place and bolted up. It required some relative lowering and lifting of the sub-frame and body to get it all lined up. So that's done and now I am struggling with the sway bar. I replaced all the bushes in the sway bar pivots and tightened the bolts up - maybe I should have left them loose and tighten them up once the mounting is in place.