Worn rear lower wishbone bushes. S-type, X350,XF models

[J44EAG]

The above Jaguar models all share is similar suspension platform.

We have long known that high miler S-types suffer from worn inner and outer bush failure which can cause problems at MOT time. As the XF and X350 models age also and accumulate miles, the same problem will affect them also.

Some years back, Bob Bate highlighted the problem in one of his excellent articles in our magazine, under a heading of "Bob Bate gets contraversial". Bob went on to describe the lack of available bushes as service parts to be "outrageous".

Why?

It is as simple as this. Only complete new individual wishbone assemblies are available at between £215 -£430 each, depending on who you source them from.

Jaguars reason for not supplying replacement bushes is that they do not consider it an approved item for repair. The story is that they are concerned that replacement of the bushes if done poorly may lead to a cracked wishbone.

Whilst this could happen if undertaken by an inexperienced, clumsy and brainless engineer, I think it doubtful in practice. Most guys doing this type of work know what they are doing. The bushes were pushed into the wishbones originally by the Jaguar parts supplier and conversely may just as easily be pushed out again using a bench press. Having been taken out, new bushes can be pushed back in again with care and the right tools. So why the hype and stage fright?

It is a nice little money spinner and will cost an owner around £800 for new wishbones plus labour and VAT. So thats a grand gone.

Short of obtaining secondhand wishbones at a current market rate of around £100 each with no real guarantee that those replacements might not have much life left in them, the only answer has been to buy new complete wishbones. Ouch!

Following a string of mails to me over the last couple of years, I decided to investigate further. My local Jaguar repair guy told me that XF bushes fitted S-types and that he was doing the repair to customers cars on a regular basis. I hadn`t the nerve to ask where he sourced his parts. I tried a Jaguar Main Dealer for XF bushes but got the standard party line described above. Not approved by Jaguar as a repair so therefore not possible to have the job done at a main dealer even if parts were available.

Then one of our members found out that Racing Green Cars in Guildford had had these special bushes made for the rear lower wishbones. They also have had oversize shell sets made up for V8 cranks which would otherwise condem a crank as scrap owning to the fact that Jaguar do not supply oversize bearings for reconditioning work! Make up you own mind as to why that is the case.

Colin Bowler at Racing Green tells me that the wishbone bushes are a relatively easy fit with a bench press and a knowledgable engineer doing the job. Sure, it is possible to crack a wishbone if one tries hard enough to be clumsy, but given one confidently knows what one is doing, there really should be no reason why a repair of this nature should not be effected without pulverising the wishbone or its new bushing.

The wishbone is fitted with a large Metalastic bush on one chassis location, together with the ball type bush at one other chassis location point and the other at the outer end of the wishbone where it links with the bottom mount on the rear hub carrier. Two bushes in all that need replacement on each wishbone. In practice the Metalastic bushes do not cause problems and will rarely require to be replaced.

It is recommended that all bottom wishbone bushes are replaced in one hit. If one has worn, then the other three on the car will not be far behind. So, it is two new bushes per wishbone making a total of four required to repair the car.

Wishbones should be checked for corrosion issues especially around and inside the wishbone voids where the bushes locate. This must be in perfect order and not be eaten away due to galvanic action.

Racing Green can supply bushes at a cost of approximately £50 per bush. So that is £200 for the parts plus a couple of hours labour plus VAT.

Rather different from a £1000 bill.

I reiterate that this is not an approved Jaguar repair and that it is an "on your own head be it" scenario if problems occur after fitment.

I am purely the message sender in this post and cannot endorse this proceedure either individually or as the JEC S-type Co-ordinator. Nether do I have any links with Racing Green.

Interesting, eh?

Mike

[Brakebuster]

i have , on my own , on my drive ,changed out my lower wishbone bushes and lower ball joint due to wear on the inside of my front tyres , i do however have a 12 tonne press and heavy duty jacks and axle stands, and a spring compressor ,

this is a very heavy and tricky job for the home mechanic, but there is no reason, as mentioned above , that a competent person cant do this job satisfactorily ,

my only addition to the above comments are that a full 4 wheel alignment is required after fitting, as the mounting bolt for the lower wishbone bushes in offset for lower camber adjustment, and removal blows this setting away , and new bushes negate the original settings,

and dont let anyone tell you the XJ8 ( in my case ) doesnt have adjustable rear wheels, as the camber is adjustable at the rear by a similar method tot he front with an offset bolt ,

money can be saved , but be aware that quite a bit of work is involved ,

BB

[J44EAG]

Thanks for the input BB. Always good.

Having read your posting, I phoned Colin at Racing Green again.

He confirms that the new bearings are concentric bolt through tube and hollow ball manufacture. As such, the bolt will always lay perfectly within the centre of the bearing. The through bolts for both the hub carrier mounting and the chassis mounts are ordinary plain bolts and do not have cam type eccentricity associated with adjustable camber type set ups.

If one assumes that the car camber was correctly set up when the car was built, fitment of the new bushes will restore those settings to the original value which should be correct. It is difficult for it to be anything else but as it should be. Racing Green have not found it neccesary to re adjust any car on which they have done bush referbishment work.

Colin stressed the importance of cleaning the voids of corrosion and dirt prior to removal of the old bushings. A vernier depth guage should be used to ensure the new bushes are located exactly to the same depth in the wishbone as the old parts. Other than that, the job should not be behond the abilities of an experienced engineer to assess and carry out the work to original dimensions.

The S is fitted with coil over damper springs. These do not require to be dismantled, other than to remove the bottom damper mounting bolt, thus freeing the damper from the wishbone. Obviously the anti roll bar vertical link will need to be detached from the lower wishbone. This is a simple 10mm nut which can be removed with a 10mm socket and wrench. Nothing difficult about that.

So thats the latest on the matter. This type of bush fitment and referbishment is not uncommon with many other modern cars and is not unusual in any respect. It is certainly not rocket science. For us the problem has been that until we discovered that referb parts were available, we were limited to fitting new wishbones at huge cost. Now we have an alternative solution which has been proved to be effective, economical and safe. Were that not the case, Racing Green would not be fitting or supplying these parts to the general public for self fitment or to their sales cars or their customers vehicles.

Whilst Jaguar may not approve of the practice for what ever reasons, that does not itself preclude fitment of these bushes as unsound, dangerous or illegal. Provided a suitably qualified and experienced engineer fitting such bushes feels confident that what he has fitted is suitable for the perpose and he is happy with the end result, I personally see no reason why such bushes should not be fitted. Purchasers of new bushes should also understand any potential risks and decide for themselves which direction they wish to proceed.

Mike