Hi all!
This was my experience retrofiting the self-leveling system on my 88 XJ40
VDP. Please be advised that there is machine work involving highly
sensitive parts, and all this is not for the faint of heart! And study well
all the steps so you can have a good mental picture of the whole job
process.
Things to buy: Two spring cotter sets (the round pads that hold the lower
part of the springs to the shock, 3 pieces per set) for non-self leveling
rear struts from Jaguar dealer (around US$80) and a pair of non-self
leveling shocks for the same model year car as yours from your trusted
source. I got mine from the NAPA warehouse in Miami for about US$40 each
and come with a lifetime warranty, so if they ever fail I can get them
replaced for new ones, you won’t get this warranty from original Jaguar
shocks! NAPA seems to sell Monroe shocks under their own NAPA brand. If
you go for Monroes’, don’t get the Sensa-Trac shocks as they won’t last and
you won’t like how they ride, trust me!).
Dissasamble the old strut assemblies and take both the old and new shocks
plus all anciliaries to your trusted machine shop. You should know that the
springs that come with your self-leveling car lack one turn compared to the
non self-leveling springs. Otherwise, they both have the same load carrying
capacity. For this matter, if you would put them back on the normal manner
your car’s rear will ride an inch lower than designed. Now take a look at
your new shocks. They come with a ring around the middle of cylinder. This
ring rides on a groove cut into the cylinder. The cotters you bought at the
Jaguar dealer ride, along with the springs, on top of this ring. That’s
right, a quarter of the weight of the car rides on this seemingly weak ring!
You and your machine shop mechanic should know this so you know how
important it is for the next step to be done carefullly! Have the machine
shop cut an EXACT duplicate groove one inch higher (towards the threaded
rod) on the shock cylinder and place the ring on the new groove. Please
advice the machine shop that contents within the cylinder are under high
pressure so they will take messures on not overheating the shock wile
cutting and also not overcutting! Now take the old shocks and cut the
piston rod at 3/16" or 3mm below the step on wich the old shock’s big washer
rode. Drill this cutted piece of the rod at the middle to the same diameter
of the new shock’s big washer’s hole so the rod will be able to slid snuggly
into the new shock. Now slid the new shock’s big washer onto the new shock
and then slid on top of it the cutted and drilled piece of the old shock’s
rod. Measure how long it needs to be cutted down to allow 1/2" or 13mm of
the new shock’s thread to show. Screw down the old shock’s nut into it and
cut the rod with its nut to lenght. Now assemble this rod into the strut’s
upper base as you will with a new self-leveling shock. You will need
somebody to push down the upper washer against the bushings so you can start
the nut down its thread. Afterwards, tighten to spec torque (an impact
wrench will help you screw it down without the rod turning aloose). Now
slid the big washer down the new shock and have its boot (bellows) fitted to
the big washer. Assemble the strut assy back. The old bushings and rod
will take the place of a non self-levering assy’s. Tighten nut to spec
torque . The 3/16" or 3mm you left below the old shock’s rod will allow the
new boot (bellows) to fit tightly against it. That’s it. Now you have a
non self-leveling setup for less than half of what it costs to buy the
dealer’s retrofit kit. It’s been working fine for me and my kitten feels
incredibly surefooted compared to the raging bull it was before! Please
note that If you opt to use the retrofit kit but wish to re-use your
original springs, you will need to do the groove job too on the new shocks
to regain your normal ride hight. Hope this will work as good to you as it
has to me!
Fernando F. Achon
Panama City, Republic of Panama
88 XJ40 VDP