MetalCloak DuroSpring Bump Stops and Extensions, Rear Upper, Ineos Grenadier

Factory bump stops on the Grenadier do exactly one thing: they stop the suspension. They do it hard and without warning, and the longer the shocks you fit and the more travel you ask for, the more often you feel it. This kit changes both when the suspension reaches the end of its travel and how it behaves once it gets there.

You get two Delrin extensions that drop the bump stop contact point by 2 inches, plus two DuroSpring bump stops made from micro-cellular urethane. The extensions keep the up-travel limit correct once longer shocks are installed, while the DuroSprings absorb the compression energy and release it slowly instead of bouncing it straight back.

Key benefits

• Delrin extensions drop the bump stop by 2 inches – with longer shocks fitted, the suspension stops where it should, before components run into each other.
• Micro-cellular DuroSpring bump stops – they compress progressively instead of rebounding like solid rubber, which means a softer entry into the bump stop and less impact fed into the body.
• Shock protection – a controlled end of travel takes part of the load off the shock internals, especially at speed over rough ground.
• No maintenance – no sliding parts to bind or seize, no fluids to change and no gas to charge.
• Designed around the RockSport Black shocks – the kit was built as part of the MetalCloak suspension package for the Grenadier.

What's in the kit

• 2 × upper rear bump stop extension
• 2 × upper rear DuroSpring bump stop
• all required hardware

Technical data

• Application: Ineos Grenadier, 2023 and newer
• Position: upper rear bump stops
• DuroSpring material: micro-cellular urethane
• Extension material: Delrin
• Bump stop contact point lowered by: 2 inches
• Installation difficulty: easy
• Installation time: about 30 minutes
• Body modification: none

Who it is for

Mainly for lifted Grenadiers running longer shocks, where the factory travel limit no longer matches the setup and has to be re-established. It also earns its place on trucks used off-road or travelling loaded, where the suspension regularly reaches the end of its travel – in ruts, dropping off ledges and on fast, rough gravel.

Installation notes

MetalCloak rates the install as easy: the parts go into the factory rear bump stop locations, nothing needs cutting or welding, and the job takes around half an hour with basic hand tools. The kit covers the upper positions only – MetalCloak intends it to work together with the lower adjustable bump stops, which set the actual travel limit.

If you would rather not do it yourself, our workshop can handle the installation and help you match the rest of the suspension. Szekla4x4.pl is an authorised MetalCloak dealer and works on this kind of conversion regularly.

Why it is worth it

• It solves a specific problem that appears once longer shocks are fitted – an end of travel that arrives too late and far too hard.
• Micro-cellular material instead of solid rubber gives a predictable, damped stop rather than a hit.
• A maintenance-free set you fit once and can then forget about.

Not sure whether this kit suits your suspension setup? Get in touch and we will help you match it to your lift.

Frequently asked questions

What do the bump stop extensions actually do on the Grenadier?

They lower the bump stop contact point by 2 inches, so the suspension limits compression earlier and does not bottom out harshly, while still using the available up-travel. Combined with the DuroSpring bump stops this gives smoother engagement and better control.

How do DuroSprings compare with the factory rubber bump stops?

They are made from a micro-cellular material that compresses progressively instead of rebounding abruptly like solid rubber. That reduces impact harshness, protects the shock internals and gives a more refined feel on and off road.

Is the installation difficult?

No. The extensions and bump stops bolt directly into the factory rear bump stop locations using basic hand tools. MetalCloak quotes around 30 minutes and no cutting or body modification is required.

Do I need the lower bump stops as well?

This kit covers the upper positions. According to MetalCloak the upper DuroSprings improve bottom-out resistance and are designed to work together with the lower adjustable bump stops, which set the proper travel limit.

Which model years does it fit?

The Ineos Grenadier from the 2023 model year to current production.