MetalCloak Traditional Shim Stack Conversion Kit, RockSport BLACK 2.5in Shocks

The RockSport BLACK leaves the factory with MetalCloak's own parabolic valving (patent pending #63/743,954). It was designed to be simpler, more repeatable and more forgiving to assemble — and for most owners that is an advantage, not a limitation.

This kit does the opposite: it converts the parabolic valving to a traditional shim stack, the platform familiar to anyone who has ever tuned a shock on the bench. You get a set of precision-machined steel washers that rebuild the piston into a standard configuration — and the damping curve is then yours to build with your own shim selection.

Note: tuning shims are not included

MetalCloak states it plainly: the kit includes only the washers necessary for the conversion. The thin shim discs that build the actual damping curve you select and buy yourself — and that is the whole point of the exercise. The parts in this kit are 0.10in (2.54 mm) thick; they are the structural elements of the stack, not tuning shims.

If you do not have your own shim stock or a clear idea of the curve you are after, this product is not for you. We would rather say so than sell you something that ends up in a drawer.

Key benefits

• Full control over the damping curve – in a traditional shim stack every change of disc thickness and diameter translates into a predictable change in the curve.
• A familiar service platform – if your workshop already works on standard shim-valved shocks, a converted RockSport BLACK fits the same process and the same shim stock.
• Precision-machined steel washers – three sizes, twenty pieces, made for this particular piston.
• An hour of work, nothing touched on the vehicle – this happens inside the shock, during a service.
• A factory kit, not an improvisation – the conversion was designed by the shock's own manufacturer, not by someone on a forum.

Washer dimensions qty ID × OD × th. 12 0.51in × 0.75in × 0.10in 4 0.51in × 0.88in × 0.10in 4 0.51in × 1.82in × 0.10in In metric: bore approx. 13 mm; outside diameters approx. 19 / 22.4 / 46.2 mm; thickness 2.54 mm.

What's in the kit

• 12 × washer 0.51in ID × 0.75in OD × 0.10in
• 4 × washer 0.51in ID × 0.88in OD × 0.10in
• 4 × washer 0.51in ID × 1.82in OD × 0.10in

MetalCloak calls these parts "shim" in one place and "washer" in another. Their thickness (0.10in) makes clear they are structural elements of the stack rather than thin tuning discs — which is consistent with the manufacturer's note that tuning shims are supplied separately.

Technical data

• Application: MetalCloak RockSport BLACK shocks with a 2.5in body
• Function: converts parabolic valving to a traditional shim stack
• Washer material: steel
• Piece count: 20 (3 sizes)
• Tuning shims: not included
• Installation difficulty: easy
• Time to install: approx. 1 hour
• Body modification: none
• Shipping weight: approx. 0.45 kg
• Country of manufacture: USA

Who it is for

For workshops and for people who tune their own shocks and want full control of the damping curve — not for someone looking to "upgrade" their RockSports. This is not an improvement, it is a change of philosophy: you give up valving designed by the manufacturer in exchange for a platform you have to tune yourself. If your shocks work well, there is no reason to change anything inside them.

It makes sense when: your vehicle's weight or the way you drive it does not suit the factory curve; you run a workshop that already works from its own shim stock; or you are building a competition vehicle and want to match damping to a particular course.

Installation notes

MetalCloak rates the work as easy and allows about an hour, with no modification to the vehicle — it happens inside the shock, with the shock stripped down. That means experience servicing reservoir shocks and conditions clean enough to keep the system contamination-free.

If you would rather not do it yourself, come to us: Szekla4x4.pl is an authorised MetalCloak dealer with a workshop specialising in off-road suspension. Tell us the result you are after and we will help select the shims and carry out the conversion.

Why it is worth it

• A shock costing thousands that can be not only serviced but re-tuned to your own spec.
• The kit comes from the shock's own manufacturer — the dimensions are made for this piston.
• After the conversion the shock fits standard tuning practice and standard shim stock.

Not sure the conversion makes sense for your vehicle? Get in touch — we will tell you honestly, including when the answer is "leave the factory valving alone".

Frequently asked questions

Are tuning shims included?

No. MetalCloak states plainly that the kit contains only the washers needed for the conversion. The shim discs you select and buy separately, according to the characteristics you want.

Which shocks does it fit?

MetalCloak RockSport BLACK shocks with a 2.5in body, whichever vehicle they were built for.

How many kits do I need?

The contents correspond to one shock. For an axle set, count accordingly — if you are unsure, we will write to the manufacturer and confirm before you order.

Is the conversion reversible?

The kit replaces valving components, so keeping the original parts is the condition for going back to the factory setup. If you are considering that, keep everything that comes out of the shock.

Will this make my shocks perform better?

Not automatically. The kit gives you the ability to tune, not a better result out of the box — the outcome depends on your shim selection. The factory parabolic valving is well developed and sufficient for most owners.

Does it fit 6Pak shocks?

No. This kit is for the RockSport BLACK 2.5in line only.