The Al one, was it DEW98? This article says it was but I've heard otherwise.

The cars : Jaguar X350 - AROnline

 

Just from my own point of view, the chassis in ALL RWD jags is the basic one from the 2003 S-type. This is true today in the XK, XF, XJ lines. I cannot speak about the F-type, as I have not been under one. The 2003 S-type is a modified 2000 S-type. They kept the rear suspension but totally changed the front suspension to what we have today. From what I heard, the Lincoln LS kept the old suspension throughout it's life.

I do think that Jaguar has gone too long with this suspension/chassis but it is a very well balanced setup. It has provided Jag the ability to offer the supple ride that is a Jaguar while also including the sportiness that other potential buyers are looking for.

In my opinion, ten years on the the same suspension/chassis is a very long time but proves that it was the right one out of the box.

 

I'm more interested in the unibody. Would, say, the firewall of a X350 be the same as a DEW98 car but done in Al? How about the trans tunnel or floorboards?

 

Hmm, everything I've seen said that jaguar DID NOT use the ford platform for the XJ8; there is even a comment at the bottom of that article where someone states it as such.

I know wikipedia is infallible but it lists the S type and the new XF as using the DE98 platform, not the XJ8.
Ford DEW platform - Wikipedia, the free encyclopedia

I too have been interested in the aluminum chassis but have not found too much on it. I did find an interesting tidbit on Audi's aluminum chassis where the engineers talked about how much better it was in collision ratings because of aluminums superior energy absorption.

 

found this on the UK XF forum:

"The XJ and XK are not on the DEW platform. They are on a Jaguar specific alluminium chassis where the DEW platform is steel"

That's just the body that the chassis bolts to.

The chassis in terms of uprights, suspension arms, bushes, subrames etc is the same on S-Type, XJ, XK and XF. This is the bit that was completely re-engineered by Jag and is what the dew98 chassis refers to. If you look under a 2000 MY S-type and a 2002 MY S-Type the chassis is very different, since then they are all the same.
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How the XF is put together [Archive] - Jaguar XF Forum


sounds like RoyalBlue's observation; the basic backbone is the same...but nothing definitive.

 

I agree the link is the LS and the S-Type and they were very much co-developed rather than Ford pushing anything and allowed Jaguar to do much more than it could on it's own. The LS took a de-tuned smaller 3.9L version of the Jaguar 4.0L V-8.

The XJ and XK were Jaguar NOT Ford.

See this design article from the introduction of the DEW98 in 1999. Note the comments from the Jaguar chief program Engineer. This is an industry publication.
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Of course there is a small amount of the DEW98 in the late model Mustang. Just too expensive to build the DEW98.

Ford D2C platform - Wikipedia, the free encyclopedia
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