Rear Suspension woes..

[JaggyWag]

Greetings All, new on here but have been grappling with a S3 2+2 for the last year! It is 40 years old and off the road for the last 20 years. I think Peter C's helpful book warns against buying someone else's problems, but I think it's a case of 'I've started so I'll finish'..! I'd very much appreciate a bit of advice from anyone who can help, please?

Car in for wheel alignment checks and have discovered that the OSR is a long way out and cannot be adjusted (probably explains why the car is hard to push!) Thinking is that the rear subframe is bent, suggestive of the car being 'kerbed' hard at OSR wheel but hard to see any structural damage underneath with the naked eye. Anyone had a similar experience please? Is this a common occurrence? If I have to fit a new subframe, I gather that XJ6 and XJS frames will fit. I have located the latter but think it is a later version with outboard brake discs. Does anyone know if this will fit my car, please? Most grateful for any thoughts!

[MarekH]

Dear Anon,

No they won't fit. You'd want a subframe from an old s-type (or perhaps a 420G also - I'm sure someone else will chime in). Use the search facility to confirm that. Also note that the carrier between the differential and lower arms is probably different for those cars so you'd need to keep hold of your own one.

New cages are also available.
Feel free to use a real name - this is more MFI than MI5.

kind regards
Marek

[Heuer]

When you say a "long way out" - how much? This is the alignment report on my FHC: http://etypeuk.com/forum/viewtopic.php?t=4991 where the rear left toe is 3.7mm compared to 0.4mm on the right. The camber is within specifications but there is no published toe specification for the rear because there is no adjustment. However it is generally accepted that 4mm of total toe in at the rear is about right for the road. Excessive toe increases tyre scuffing and results in tyre wear and drag on the vehicle. Excessive toe-in, or positive toe, increases scuffing on the outside of the tyre. Excessive toe-out, or negative toe, increases scuffing on the inside of the tyre, and in some cases can cause a wandering problem.

[JaggyWag]

Thanks Marek, the name is Peter by the way, the tag dates to when my daughter first tried to say 'Jaguar' and that is how it came out - hence I am quite attached to the name!

So, to be clear, the only frame that will fit is the S-Type and not the XJ6 or XJS with the inboard discs?

Such as this one maybe:

http://www.ebay.co.uk/itm/JAGUAR-420-S- ... 1c394ec093

Many thanks for your kind assistance.

Peter

[JaggyWag]

David

That's actually very helpful, thanks, as I can refer these points (including those from Pete) to the garage carrying out the work.

Can't remember what they said about how far out it was, will ask them. Interesting thing is that all the signs are that the rear frame was taken out by the previous owner as the mountings look new, although I don't think the trailing arm bushes have been changed.

Many thanks.

Peter

[tinworm]

Hi , a possibility for consideration is the radius arm turret position (turret welded to floor ) as if this was positioned too far forward this would have the effect of pulling the axle around on its rubber mounts - this could be enough to affect the toe -in on that side . This sort of thing can happen to a car that has had new floors fitted.

regards Barrie

[MarekH]

Dear Peter,

Don't necessarily believe that an ebayed cage will be better than your own - there is a reason why stuff ends up on ebay - it's because the current owner doesn't want it.

I'd investigate where the geometry mismatch comes from first. As already pointed out, it may not be the cage.

kind regards
Marek

[Heuer]

Agree with Marek - if it is the cage it is likely both sides will be out, if one side then the trailing arm would be the suspect. See if you can get hold of the alignment measurement report and post it here.

[Alty Ian]

Hi Peter

The rear frames can be very difficult to get back in straight especially if any work has been done to the radius arm mounts etc. I wouldnt just assume its bent, more likely its incorrectly fitted, You need an accurate survey and measurements to work out whats happening.

cheers Ian

[PeterCrespin]

Car in for wheel alignment checks and have discovered that the OSR is a long way out and cannot be adjusted (probably explains why the car is hard to push!) Thinking is that the rear subframe is bent, suggestive of the car being 'kerbed' hard at OSR wheel but hard to see any structural damage underneath with the naked eye. Anyone had a similar experience please?

Please to essplain what or how she is 'long way out'?

The important and hard-to-fix parameter can be checked in two minutes with a tape measure. Take the hub centre to hub centre distance, or rim edge to rim edge if you're feeling lazy or have no help. It hardly matters which points you measure to/from because the only issue is how different the two same measurements are. If the wheelbase-type reading is the same then I assume you're talking about camber? There would have to be a pretty humungous wheelbase difference to make a car hard to push IMO and no amount of camber difference would matter to pushing. For the wheelbase to be smacked out of line to the point of making the car hard to push, you'd see with the naked eye that one wheel was displaced in the wheel arch or the two wheels seemed distinctly different fore and aft in their arches.

Skidding sideways on ice or oil and smacking a kerb hard with one back wheel can do nasty damage if you suspect a trauma cause, but first I'd need to know what is is that's a long way out.

Pete

[JaggyWag]

Thanks to everyone for the helpful observations. Will try to get the measurements and post them.