Parts Guides

Why timing belts are time-and-mileage critical, what happens when one fails, and the brands worth specifying.

Reading the wear indicator, picking the right friction grade, and avoiding the most common UK pad-replacement mistakes.

How to decide when discs need replacing rather than just inspecting, plus the minimum-thickness rule and which brands actually meet OE.

How glow plugs heat the combustion chamber, what wears them out, and why one failed plug usually means the others are close behind.

How heat range, electrode material and gap affect engine performance — and why generic substitution can cause misfires the OBD can't explain.

Power-steering filters, automatic gearbox filters, DPF sensors and the filters most service schedules forget about.

Why the cabin filter affects heater output, blower-motor life and allergens — and the brands worth paying a little extra for.

What separates a £4 oil filter from a £12 one — and why the difference matters for bearings, turbo and the whole bottom end.

Why diesel fuel filters can't be skipped, what the water separator does, and the brand choice that protects the high-pressure pump.