In a car with the performance of the M5 or M6, stopping power is a priority. The front brakes can be overhauled for £300 using discs and pads from Euro Car Parts - these are OEM components but not branded as BMW. You'll need to find a trusted specialist to do this work, and factor in their labour, but it's still a significant saving over the £1,200 a BMW dealer will charge. The same franchised dealer will also relieve you of £775 to do the rear discs and pads, while original spec aftermarket parts can be bought for just £250, plus labour for a specialist to fit them. There is a Brembo kit available to upgrade the stoppers for track day work, but for road use the standard set-up is fine. You could compromise with fast road pads from EBC should you wish though. New brake fluid in the system is a £71 deal at a franchised BMW outlet.
Big car with big power, so keep rubber tip-top
Although the M5 and M6 are identical mechanically, they use different alloy wheels, so be wary of any car not sitting on the original spec rims. Larger aftermarket wheels are also a warning sign, as they can rub on the bodywork and undermine the handling. As standard, 19-inch wheels were fitted, but BMW offered an 18-inch winter wheel and tyre package that's worth having if the car is offered with both.
Rear tyres are 285/35 x 19 and will last, on average, up to 15,000 miles. The fronts are 275/35 x 19 and manage about 20,000 miles. Expect to pay around £250 per tyre to replace them with premium brand rubber.
Suspension on all of these V10-powered models is reliable and durable. You may need to budget for new dampers on higher mileage cars, but that's nothing out of the ordinary. It will be more expensive if the car has the EDC electrically adjustable items fitted however.
Sticking with the suspension, vibration felt through the steering could be a wheel that needs balancing or might be worn control arms. Neither is expensive to put right.
PHer's view:
"When it’s good, the M6 is amazing, but you do have to put up with a lot during the daily drive. I loved it for three years, but didn’t miss it when I swapped into a 640d."
Charlie Allen