Hopefully, one or several of you can shed some light on this, and, yes, I searched the forum for answers...

Here are some of the threads I found which are most similar, but they're for different models of Jaguar and involve slightly different questions:
https://www.jaguarforums.com/forum/x...ackers-214296/
https://www.jaguarforums.com/forum/x...struts-245636/
https://www.jaguarforums.com/forum/x...quired-221702/

Anyway, I'm nearly finished with my almost total suspension rebuild (delayed due to work, as well as several companies sending the wrong parts), but I noticed that on my original front suspension setup which I completely removed, I had both the "Spring Packing Washer" and "Spring Packer" (also referred to as "Spring Seat" and "Spring Lower Insulator") on each spring. However, on my rear suspension, I ONLY had the Spring Packing Washer on each spring, without a Spring Packer. See pic below from another model (XK8 ?) for reference...

Both Spring Packing Washer and Spring Packer Included

Here's what my original Spring Packing Washer and Spring Packer from one of the front springs look like (the Spring Packing Washer sits on top of the Spring Packer, which sits on the damper's permanently installed steel cup)…

My XFR Front Suspension Original Spring Packer and Spring Packing Washer

I ordered four new Spring Packers because they were so cheap (finally, at least something was), but I was surprised when I got to the rear springs that there were no Spring Packers to replace.

Further, I'm re-using my original Spring Packing Washers because they seem to be in good shape and because I also can't find them listed in any XFR/XFR-S parts diagrams. See below for reference...

SNG Rear Shock Diagram

I purchased four new top shock mounting kits which contained the "Upper Mount," "Spring Upper Insulator," Top Nuts, Bump Stop, and Washer, but it didn't come with the Spring Packing Washer or Spring Packer (I didn't expect it to).

So, I'm at a bit of a loss. If the Spring Packing Washers are needed for the spring to fit snugly into, which they definitely appear to be, why are they left out of all of the diagrams and seemingly unavailable for purchase (unless they come included with new OEM springs, but aren't referenced or alluded to in the terrible drawings???)?

Further, why did my car only have the Spring Packers on the front springs and not the rear (I bought it new and have never had any suspension work done)? Is that normal, and, what purpose do the Spring Packers actually serve if they're being left off and/or used in conjunction with the Spring Packing Washers?

Lastly, since I'm installing new Spires springs, which I think only drop the ride height by about 12-15mm, I'm on the fence about whether to leave the new Spring Packers I purchased on the front springs and also install them on the rear springs, or some combination thereof.

Thanks to any/all who can help me understand this better and make a more informed decision.

 

Another detail I just noticed is that the workshop manual actually has a diagram of the rear suspension with what appears to be both the Spring Packing Washer (it looks like it's already installed on the bottom of the spring) and Spring Packer, although I didn't find any further details.

 

These parts are shown in the Jaguar EPC and were available from my local Jaguar dealer last April. I still have a couple of new spares. From my 2012 XF Portofolio I observed that adding or deleting the packers allowed me to level my car perfectly. Someone had installed a new shock and spring without a packer and it lowered the the ride height on that side of the car. Rear shocks had them installed.

 

I wish I had a better sense of how my new Spires springs will make my car sit. When I removed my suspension, in addition to leaking bushings, my front driver spring mount was 100% gone (absolutely no rubber inside, which was causing HUGE clunking), and the rear springs actually looked so compressed that they seemed shorter than the new Spires springs. I've had my car for almost 11 years, so it's hard to even remember what it originally looked like. It's even harder to comprehend what all new suspension parts with Spires springs is going to look like, and it's a lot of work to pull the springs on and off to try to dial in the looks with the spring packers, especially until the new springs settle, but I'm not sure how else to go about it. Grrrrr...