Available UK Time 10am - 4pm on ++44 (0) 1793 290 620 (Mon - Fri)
Keep your Jaguar’s cooling system performing at its best with this OEM expansion tank pressure cap, part number MJA4440BA-O. Designed for the Jaguar X-Type, X100 (XK8), and X308 (XJ models), this cap is engineered to maintain the correct system pressure at 1.0 bar, ensuring reliable engine cooling and protection against overheating.
As an original equipment manufacturer (OEM) component, this cap is built to the same standards as the part fitted at the factory. It guarantees proper fitment, durability, and performance—unlike cheaper copies that may compromise your vehicle’s cooling system.
If your existing cap is worn, leaking, or no longer holding pressure, this genuine-spec replacement is the ideal solution to restore confidence and reliability.
Suitable for the following vehicles:
X-Type
VIN range: ALL
X308
VIN range: From 812317 to F59525
X100
VIN range: ALL
Our team has access to the same JLR parts catalogue as a franchised main dealer. Share your UK reg or chassis number and we'll confirm fitment before you order — free of charge.
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