I was browsing the UK S-type forum and found a post from someone with a serious rust through issue on the sills, aka rocker panels on this side of the pond, which can only be discovered by removing the body trim under the door. In that post is a link to some pretty graphic pics: Jaguar Forum.co.uk • View topic - What lurks beneath my plastic sill

I read the Technical Guide (attached) which says that the body in white received zinc treatment, which would lead one to beleive this shouldn't happen.

Has anyone else had/seen similar problems? As I intend to drive this car through the winter perhaps I need to get the good old Waxoyl out and spray some in the body cavities.

 

Wow Andy nice find.

I have always wondered about the corrosion effect, with all the underbody plastic coverings ever since I laid eyes on the underneath of ours.

I relocated from the eastside of Cleveland and know the amount of salt dumped on the roadways there. I used to have a hobby job, plowing for the Villiage of Reminderville. If I still lived where salt is an issue, albeit a lengthy process, I would remove the plastics in the spring and get a couple of underbody car washes.

Heres a link about door corrosion from a fellow Ohioian and forum member: https://www.jaguarforums.com/forum/s...ty-test-36545/

As stated in the UK forum discussion, maybe its a pre-face lift issue. The pictures are the first MY run in 1999.

 

Rick,

I was confused by the above Corrosion Warranty Test link and hope you might be able to clarify.

The thumbnail pictures with views of side sills or rocker panels appear to be from an earlier MY S-Type, as you mention first MY 1999.

However the description of owned cars under the signature says "2005 recently traded S-Type". And comments throughout the thread are suggesting a 2005.

Just curious.

 

Member JOsworth, the link above recently just sold his 1 and only 2005 S Type. That is the one in the links pictures.

 

This is a problem that continues to plauge cars of all makes. GMs like Grand Prixs, Monte Carlo ect. are particuarly prone even with the zinc coatings used. Road salt will eventually eat through the coating and when it does, the steel melts like butter. Replacing sills is a very labor intensive operation and the parts are not cheap. Usually well over the worth of the car.

Bad thing is the sills on a unibody are a major structural component. Sort of take the place of the frame rails on an old body on frame design. However, you see a lot of old gm cars still driving about with rot hanging out the bottom.

 

I have also read this thread a few months ago and promptly took my sill covers off my 1999 model S type to have a good look. Mine exhibited signs of surface rust but nothing as bad as that shown.

The roads in the Uk are regularly given the salt treatment in the winter months and together with the copious amount of rainfall we get makes a very effective rust promoter.

My other cars also have plastic sill covers and one (a Rover 400) now has large holes in the sills after a good poke with a screw driver. I have just cut out the damage sections and welded replacement panels to make good again.

I am now instigating an annual check of the sills by taking the covers off, cleaning out the muck and spraying on a rust proof wax before re-fitting the plastic covers. I have also loaded the inside of the sills with similar rust proof wax.

I think this is one issue to be aware of and monitor?

 

Rick:
Interesting thread about the door corrosion. I went out and checked mine after seeing those pics - none to be found. The design of the door seal would seem to trap salty gunk against the door frame, and perhaps should be given special attention when washing the car.

That thread also referenced a TSB about rear footwell flooding, the solution for which was to drill a drain hole in the top of the sill, and then cover the hole with a threshold plate. I am not sure what that was supposed to do. Is the water supposed to find its way under the plate and out through the hole? Does that hole lurk under the threshold plates of the later cars?

In any event, pulling that sill cover and painting the area with POR15 or some similar product would be a good idea, and then injecting rust preventor into the box section. Eastwood is running a sale on this stuff: Internal Frame Coating w/Spray Nozzle

 

That TSB you mention was done on my car by my dealership.

I think the inner and outer rear door seals at the bottom of the door was trapping water. When you opened the door you got your shoes washed for free!

The Jag "fix" was to drill a hole in the tread plate which allowed the water to drain directly into the sill (rocker?). The rsulting hole was covered by a fancy stainless steel tread plate which has a couple of cut outs to drain the water.

Had another "professional" Jag "fix" by the dealership.
Water was pooling in the base of the boot (trunk?). The dealership simply drilled a hole through the base.

I bet Mercedes, BMW, Audi would have a far more technical solution?