2005 Porsche Boxster (987)

5L

Front tyre size for 987 Boxster. Already ordered rears (265/40 R18) per Euromaster order NL3694987 — these are the matching fronts. SportContact 7 is an excellent OE-grade choice for the 987.

Always replace valve stems when fitting new tyres on a 7-year-old set. Rubber degrades and can cause slow leaks — especially relevant given the repeated tyre pressure corrections noted in APK records (2025 and 2026).

Persistent steering vibration at speed despite previous balancing suggests possible wheel/tyre runout or poor-quality weights. New tyres with fresh precision balancing should resolve this — ask fitter to use road-force balancing if available.

The APK records show tyre pressure corrections at both the 2025 and 2026 inspections. If TPMS sensors are fitted, replace the rubber seals and valve cores when mounting new tyres — sensors are ~7 years old and seals harden. Prevents slow leaks and false warnings.

Rear tyres for 987 Boxster — already ordered per Euromaster confirmation NL 3694987 (26 Jun 2026). 265/40 R18 is the correct OEM rear size. Pair included here as a tracking reference; confirm fitment appointment at Euromaster Amsterdam Zuidoost.

Persistent high-speed steering vibration after balancing strongly suggests worn front wheel bearings on this 142,000 km car. No bearing replacement is recorded in the full service history. SKF or FAG aftermarket units are reliable and significantly cheaper than OEM. Have both sides inspected; replace as a pair if worn.

Worn outer tie rod ends are a common cause of high-speed steering shimmy on the 987 and have never been replaced per the service history. Moog or Lemförder aftermarket units are OEM-equivalent quality. Replace before or alongside the new tyre fitting — new tyres will highlight any remaining play.

Worn strut top mounts and their bearings cause vibration and steering wander at speed on the 987, especially at this mileage. No replacement is on record. Febi or OEM units recommended. Ships to NL; alternatively available via Rennsport Breda who already service this car.

A 4-wheel alignment is already included in the Euromaster order (Uitlijn combideal, EUR 95). With 7-year-old tyres removed and new rubber fitted, alignment must be reset — especially if tie rod ends or suspension components are replaced. Confirm the alignment is done after all suspension work, not before.