A good way to do lower rear arm bushes is to use a 44mm holes saw with the teeth ground off! This makes an idea mandrel as it is just the right size to pass through wishbone registers and will slip over the rubber gaiters on the bush without damaging them when you come to fit new parts. I find the job is made much easier if you heat the wishbone register with an electric heat gun to about 140 degrees which expands the wishbone slightly and will help the old bush to push out easily and without removing internal register metal. Don`t worry about upsetting the heat treatment of the wishbone as temperatures have to go to well over 200 degrees for over a quarter of an hour before the metallurgy of the wishbone becomes altered.
These spherical bushes are quite a loose fit in the register but even so you need to keep frictional material removal down as much as possible. Take precise insert dimensions with a vernier before you push an old bush out. Use a marker pen and write the outstand dimensions on the wishbone before you remove a bush. I prefer my bench press to fit and remove bushes as good control can be used during the work.
When fitting a new bush, ensure all old corrosion within the register is removed together with any metal burs, dings or other defects before you fit a new bush. Again use a heat gun on the wishbone register to expand it slightly. It is also a good idea to put your new bushes in a freezer overnight to make them contract in size. The expansion of the wishbone and the reduced size of the bush when applied together makes for really easy fitting. Just get the outstand depths right and the job is done.
I`ve just done the front lower wishbone bushes on my X350 which use the same "banana arms" and bushes as the pre-face lift onwards S-type and the XF. When those bushes fail, the car will drive like a demented tea trolley. In my opinion those front lower wishbone bushes on all modern Jags, including the early S-type are the most important bushes of all of them when it comes to decent handling. I now only fit polyurethane bushes to my cars because I`ve found the OE rubber based units have quite a short lifespan and I hate doing repeat jobs. Powerflex market both Black competition grade bushes and also a more acceptable Purple Series for S-type, XF and X350 models and they are not much more expensive than OE parts. They also come with a lifetime warranty which is one of the reasons I fit them. They are also dead easy to fit using just soap as a lubricant. The units i replaced on Saturday last have transformed the car. Nothing but praise for the Powerflex products. Upratedbushshop.com. They also trade as Psi Tuning and their service is excellent.
On the S-type which as you may know, is very similar to the XF and X350 as regards common parts, I also changed both front and rear ARB bushes. The rear items can be a difficult job which on the early S-type had me have to lower the rear subframe to gain access. If you have to do that, then ensure you mark EXACTLY where the subframe locates relative to the body structure. Tipex is useful for that. A few index mark lines on the structure with a corresponding line on the subframe will help you get alignment right after work has been done. ARB bushes at both ends of the car can be hard work. Changing a couple of wishbones is easy by comparison. ARB access can be difficult and you can find the saddle fixing bolts very corroded. Allow at least three times the amount of time you think it will take to change them. Not a nice job.
Take a look at my post here on the subject of maintaining the suspension, dampers, ball joints and wheel bearings on these cars. i hope it will be useful.
http://www.jec.org.uk/forums/viewtopic.php?f=200&t=8040
Mike
