Used car buying guide: Audi RS4 (2005-2008)

It was possible to specify the Sport package for stiffer suspension and a reduced ride height plus side bolsters that grip you more tightly at the press of a button. These really do clamp you tight but, before you get too excited, know that the manual adjustment that came as standard is just fine.

Being an Audi and so built like a battleship, the RS4 has stood the test of time remarkably well. Its all-aluminium engine slurps oil at an alarming rate, but keep it topped up and it appears to be bulletproof. Ditto the gearbox.

Not so the trick suspension, while corrosion is beginning to take its toll on exposed pipes. There’s a lot of alloy in the car’s mechanicals and running gear, and corrosion can occur where it and steel contact each other, so get your prospective purchase on a ramp and have a good look around. It’ll be worth it to find that on-point motor.

How to get one in your garage

An expert's view

David Stringer, workshop manager, ADS Automotive: “We’re seeing more RS4s through the workshop now as people cotton onto the model and realise it’s worth preserving. Of course, it’s getting on now and many RS4s have a long list of problems, mainly because they were owned by people who didn’t appreciate what they had and so didn’t have them maintained properly. A popular request is to replace the standard Dynamic Ride Control system with a coilover kit such as the Bilstein B14 or KW Street Comfort. KW’s V3 fully adjustable coilover kit is also popular. It’s personal preference how low you want the car to sit, but many people are choosing to run with the original ride height, which at least saves the sump from whacking speed humps.”

Buyer beware...

â–  Engine: Listen for misfires caused by tired coil packs and spark plugs that can damage the catalytic converter. Decarbonisation of the inlet valves is recommended every 50,000 miles. Check the oil cooler pipes (low down at the front) for rust and leaks. While there, scan the sump and alternator belt tensioner for grounding marks. And dip the oil; even a healthy RS4 will use up to three litres per 1000 miles.

â–  Gearbox: No serious issues have been reported, save that early cars had a clutch hose problem that was covered by a recall. A clutch will last around 40,000 miles.

â–  Steering, suspension and brakes: Check the power steering pipe from pump to rack, because corrosion is common. Listen for clonks and rattles, too. The bushes on the upper and lower suspension arms are prone to splitting. Worse, the upper arm pinch bolt can seize (it’s a steel component in an alloy wheel bearing housing); if it can’t be removed, you’re in for a new housing. Listen for the control arms knocking on full lock. Juddery brakes may just need surplus dust blowing away – or new discs, which are extremely pricey if you choose original equipment.

â–  Body and interior: Check the wheel arches for scrapes. Any rust is likely to be repair related, but a corroded battery compartment is a known condition. Check the condition of the driver’s seat bolsters. Also worth knowing The Dynamic Ride Control system hydraulically links diagonally opposing front and rear dampers to reduce pitch and roll in corners. It works; Autocar’s tester praised the car’s composure. Unfortunately, as with all such systems, preserving pressure is key. The seals grow tired and leak fluid after a time, allowing the shocks to depressurise. Repairs are expensive.