Hi,
I wanted some input on anyone who has restored the suspension or modified it to see what it compares to.

I've driven/ridden in many slightly used cars that compared or were worse than my nearly 30 year old XJS and it makes me wonder....if a 30 year old Jag suspension compares to a 5-10 year old GM,toyota, kia, etc then what was it like new?? How does it compare to a new car? I love the ability to absorb shock and not wallow that new cars have, but am aware it is because they are brand new. Obviously being 22 I've never ridden in any older car NEW. Well, a few restored muscle cars, but they have **** ride quality anyway.

As I have said a dozen times I am a student on a budget, but am wondering what it would be like and how worth it it would be to restore my suspension. I'm talking a proper all springs, shocks, bushings, ball joints ,etc etc.

It is quite a lot of money and I may pick a few things and do others later (votes for what first!) but it is just so hard to imagine anything different than how it feels now that i cant bring myself to do it.

Im sure a ride in a fully restored XJS or even XJ6/XJ12 since so many components are shared would convince me, but it is very hard to imagine on my own.

I've heard the "it isn't too soft and isn't to hard, just right" Jaguar description a lot before. But to anyone who does have a new suspension, how does it compare to a new car?
Sorry if I repeated myself several times, but I always think about it when I go over bumps and stuff (to myself:"this is quite good and it is 30 years old!")

 

I can tell you first hand that restoring the suspension makes the XJS a wonderful car. I have upgraded a few things.
Front Suspension
Poly rack bushes
Poly upper wishbone - DO NOT DO THIS... mine will be coming out soon.
New lower wishbone bushes
New 25mm front sway bar and poly bushes including links.
New front subframe mountings Poly in the front...the round ones
New wheel bearings and sleeve between inner and outer.
Original springs with shims removed
New Bilstein shocks XJR-s valving

Rear Suspension
New wheel bearings and hubs re-shimmed
New LCA inner and outer bearings
New universal joints
New radius arm bushes
New Bilstein XJR-s shocks
New 50% stiffer standard ride height springs

I don't think I missed anything, and I can vouch for the greatly improved handling, with very little loss of ride quality. The poly upper WB bushes make the front a little harsh and they have worn after only 5000km so must be replaced soon.

The poly rack bushes make the steering razor sharp and are a must if you want to improve the steering response.

 

SS
Very interesting question. People I know who have both, consider that the ride quality of the XJS is better than later models such as the XK8.

My experience has been similar to Warrjon's but not identical. There was a guy called Bob Knight at Jaguar who devoted much of his time to ride quality, and arguably his touch has never been bettered. When the XJ6 (upon which the XJS chassis is entirely based - just shortened by a few inches, all suspension parts interchangeable) was first launched in about 1969/70, it was agreed by all critics to be the finest ride/handling car available regardless of price. So that is a very good starting point.

However, and this is important in my view, this wonderful ride and handling was achieved at the expense of a certain lack of durability, that today's motorists would not tolerate. I have had my car since 1998, and done over 100,000 miles in it; but suspension rubbers, shock absorbers and even sometimes springs, have been regularly changed when the ride/handling deteriorates a bit.

FWIW, my experience has been that to maintain factory grade ride and handling, these are important:

• regular greasing of the rear axle is a must. Every 3,000 is a good idea.
• regular changing of the rear radius arm bushes is a must, at least every three years.
• play in the outboard lower wishbone bearings can ruin the cars legendary ability to track like a missile through long high speed curves. Replacing these is a pain but needs doing after about 70,000 miles
• rear springs weaken quite notceably after 50,000 miles. OE ones are best if your priority is to keep the ride.
• OE shocks also are important, but they are NOT durable if you use the car's performance, 15 to 20,000 miles max I found. I now have Gaz adjustables, more durable than the OE Boges, and you can adjust them and the tyre pressures to just about replicate the OE shocks. But it has to be said the OE shocks are a touch better than anything else for the perfect ride.
• Rear axle cage mounts need to be changed too, and as with (in my experience) all rubber in the suspension throughout the car, only use OE Metalastic brand items. Aftermarket bushes are NOT as good from the ride point of view.
• At the front, I found after my rebuild that the poly top wishbone bushes introduced a bit of shimmy into the steering, so I went back to OE bushes.
• Bottom wishbone bushes are a pain to change after about 70,000, but are essential if you want OE ride quality. But they do last well if OE ones are used.
• I agree with Warrjon over the steering rack bushes. I have JaguarSport ones which are excellent and much better than the standard design.
• Front shocks same story as the rears.
• Front subframe mountings, the 'six shot' bushes at the front need changing after about 60,000 or more than a decade. Not hard to do at all.
• Roll bar drop link bushes need doing, easy to do and again OE rubber.
• Finally, I have a theory on the gearbox mounting. When I did my rebuild I used a harder (neoprene I think) aftermarket "cotton reel" bush in the mounting, instead of the squishy OE one. I could never put my finger on it, but I felt after my rebuild that it was not quite as silent and vibration-free a car as I remembered it to be. Anyway, last autumn I changed the bush (as it was falling apart) for the OE one. WHAT a difference. I would not have believed it.

So the moral is that, as Bob Knight knew, the ride/handling thing is cumulative, and every rubber item in the "chain" needs to be there and of the correct sort, to damp out the entirety of the NVH that is generated by the engine and suspension. As long as you do the work yourself the OE bits are not significantly more expensive than the aftermarket stuff. And, to answer your question, you end up with a car that still rides better than almost all new modern cars. Just expect to replace items regularly if you want to keep it that way!

Greg

 

Greg is absolutely right in this regard. It is the systematic approach to controlling NVH along with an excellent design rear suspension that gives a properly sorted Jaguar that magic carpet ride quality.

I can give you two quite different perspectives with my Jags.

I have owned my 1994 XJS from new so I know precisely what the original factory ride feels like. My car is lightly (though not gently ) used, just 41,000 miles over the last 20 years but as others have noted, many of the ride components are composed of rubber which will decompose/wear out over time.

My car has the factory SportsPack suspension so it does ride quite a bit more firmly than the stock car but the damping is still excellent. It tends to flatten bumps rather than float over them. Over the years I have replaced many of the rubber mounts in the car though I still have some of the original mounts such as engine, front and rear subframe. These are beginning to tire so will be replaced this spring. The car was originally equipped with the much firmer rear springs and uprated Bilstein shocks and they have stood up very well with no sign of wear or drop in performance

Now on the flip side, last October I bought a 1995 XJ6 that was nearly perfect cosmetically and structurally but needed a lot of TLC in the electrical and mechanical departments. One area that needed a lot of attention was the ride quality which had deteriorated significantly. There were all manner of thuds, knocks, vibrations present and the car wallowed on worn shocks. As the ride worsens, it transmits more NVH into the cabin which itself leads to bits of trim flexing and rubbing and creates various annoying squeaks and rattles.

So over the last few months I have completely renewed the entire front and rear suspensions and all the rubber components/bearings/u-joints in the drivetrain. Each change brought an improvement until I finally restored the original ride quality.

Renewing the ride is a job you can do piecemeal over time with each change offering a small improvement. It is a lot of work but is also an enjoyable exercise with a great reward!!

I will now attend to the interior noises and then my Jag will be restored to it's wonderfully quiet, great handling and charming self

 

I was thinking of just ordering an entire rubber kit from welshent or FCP euro and replacing a few select bushings with urethane ones.
Anyone have experience with the polyurethane rear radius arm bushings?

 

IME, anything other than OEM metalastic bushings in the suspension (as distinct from the steering rack) will damage and worsen the ride; while not improving the handling or durability. And they normally cost more.

Greg

 

i agree with all original except the steering rack

is it durability your after ?

well , your car has lasted at least twenty six years, so a new original set will give you at least that again, and original feel and handling

BB

 

A sorted jag XJS will knock spots off the modern models you mention - all of which tend to be engineered for lightness (efficiency) and rigidity (predictable handling).
Priorities were different in the past as I was reminded with a sharp poke from Rolls Royce today. I have just replaced the rear gas struts on my dad's RR Silver Shadow II - well over 40 years old, as I road tested it I found myself thinking god this thing is amazingly comfortable....my daily driver? A 50k 1 year old Audi A6, sure the RR was doing 15mpg but its well worth it and preferable imo!

 

I've never driven a new Jag (never had a new car) but a 20 year Jag is still way better than a 20 year old anything else for the same money.
Obviously you can end with a dog and it will be all shake, rattle and roll but then you've just been unlucky.
Generally I just replace suspension components when they become MOT fails; I don't power slide everywhere and do traffic light grand prix, that is not what Jags are about. You even get used to the rear wheel steering when the radius arm bushes are shot at the back (different if they have actually pulled out of the chassis of course!).
Jaguars were always sold on the Grace, Space and Pace credo which is basically Comfort, More Comfort and Speed.
I've just bought a 1989 XJR-S and the difference between that and my 1988 Cabriolet (both v12 lumps) is very noticeable; the local roads consist of several inches of tarmac interconnected with miles of potholes, trenches, divots, sunken drains and all things designed to not make you want to drive very fast at all.
The Scabby Cabby just ambles through but the XJR-S with the uprated suspension and reduced assist on the steering (think supertanker when doing 3 point turns) is very noticeably different (even with probably decades old bushes in). Whilst it will never catch you out you defintely know that your **** is in direct contact with the road.
Love it!
Basically, if you want the Grace part of it, go standard; if not then upgrade.

 

Steve! Just noticed you are in Wiltshire - Swindon here, I totally agree with you about the state of the roads.

 

Swindon, know it well.
Well, actually know the carpert, rug and lampshade shops!
If you need a good Jag guy (the type that before he fits new bushes takes them apart, cleans them and puts the correct grease in) then I know an excellent place near Thruxton.
Now I know somebody is going to say 'Why on earth would anybody do that?'.
Quite simple really: some of our cars are getting quite old which means that any spare parts are (unless newly manufactured) equally as old.
NOS means New Old Stock. That means that if you buy an NOS bush or bearing it is still in its original packaging but the grease in it could be 30 years old. Probably not very greasy anymore.
Tyranrr: We have our own little Jag Club down here in the boonies; me with Scabby Cabby and the 'Blue One' (recent XJR-S, haven't thought of a name yet), Bill with XJS, XJS, XJR (350) and Alistair with a very late, very mean XJR. We are very close to Burbage if you are ever down this way.
When we get another dog I'll PM you and we can meet up for a beer.
Follow the logic people: another dog means another rug; the best place for rugs is in Swindon. Simples.

 

As the great Bob Knight said: You can only impress people with a Jaguar's refinement, not its speed.

Greg

 

Unless you have an XJ220 of course: factory car, 200mph+.
Or a Mark 3 Lister (not strictly a factory car but still a recognised production vehicle) - 200mph+

 

This is ONLY way to go IMO. My rack bushes have been in for 10000km and are as good as new. This is a worthwhile upgrade.

Can't say the same for the Poly upper wishbone bushes after 5000km they are badly worn and will need replacing, these will be replaced with OEM rubber soon.

The PU WB bushes degraded the ride significantly. I get much more vibration transmitted through the front end.

 

I have to disagree with your point on the steering rack bushes. The rubber ones make the steering vague at best and I would only use these if you want a good boulevard cruiser.

PU in the rack smarten up the steering of the XJS and make it a real sporting drive. The steering in my car is sharp, turn the wheel even a little and the car responds immediately.

 

thats what i said,

all original , except the steering rack , meaning change them to PU


BB

 

I agree with you all about the poly steering rack bushes.................. sort of.

Believe it or not, the bushes supplied with the SportsPack option were actually better than the poly replacements. When I finally had to replace my rack bushes (after 20 years) I could not source the SportsPack bushes so went with poly.

Result was a bit more kick transmitted through the steering wheel and an ever so slight degradation in turn-in response. Still the only way to go unless you can find the original SP bushes IMHO.

 

My 86 rode very nice, but with the 70K miles on bushings and shocks, I upgraded bushings and replaced the shocks with adjustable Koni's. Raised the rear 3/4" and rebushed all bushings. Had a fabulous griping ride that handled like a gocart. Just had to watch foot in curves for oversteer. Ride was a little harder, but was sportscar ride befitting the V-12. Then had to upgrade brakes, then--------! Couldn't stop making it newer and kept modifying until wife said stop.

 

Is anybody adding a rear anti-roll bar to the cars that don't have them?

 

I purchased a used factory rear sway bar and end links to install on my 95. Haven't done it yet because the body studs and additional sheetmetal supports were removed in production on all XJS's not equipped with the sportpack option. Fortunately the radius arms have the mounting brackets so they don't need to be changed. Just not had the time to undertake the task and I need to locate the "U" brackets that hold the bar and bushings to the body, they didn't come with the bar I purchased. I understand if you add the rear bar you need to upgrade the front bar the keep the under steer the same.