Picking up a snappy 500bhp M car for just £9000 may seem like an easy win, but buy a dud and the cost of repairs can be crippling
John Evans
9 December 2019

They start at around the same prices (less than £10,000) and they share the same naturally aspirated 500bhp V10 and pin-sharp chassis. But although the E60-generation M5 of 2005 is the one folk lust after, its sibling, the E63-gen M6 coupé, is actually slightly quicker. Big deal if you need the saloon’s four doors, of course, but if you don’t and you hanker after a big, powerful coupé with decent practicality and an exotic engine, the M6 could be just the car for you.

But be warned: buying a dud will leave your finances in tatters. Running one is expensive – and doesn’t the trade know it. When we mentioned ‘M6 buying guide’, the specialists we spoke to dashed for cover shouting ‘unreliable SMG automated manual!’ and ‘warranty too expensive!’. It may explain why, with dealers running scared of the cars and offering low money for them, half the M6 coupés and convertibles on one popular classified website are private-sale motors. They range in price from £10,000 to £20,000, which is top money for the model. It’s likely these private sellers will bite your hand off if you offer considerably less and sweeten your bid with cash.

Because the fact is that you’ll need a war chest with an M6 to cover incidentals such as an oil service, brakes and premium tyres, plus likely repair or preventative work, including a new clutch and flywheel, throttle actuators and big end bearings. Regarding that last item, that’s only something to be wary of on higher-mileage cars but a new clutch and flywheel could be required from just 30,000 miles.

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Have we put you off BMW’s big coupé? We don’t mean to because its foibles aside, it’s a sublime motor that, when push comes to shove, feels just that little bit sharper and more planted than the M5. To some extent, that’s because it’s 50kg lighter, due in part to a carbonfibre roof that also helps make the car’s centre of gravity 60mm lower. It has a slightly wider rear track, too.

Launch control permits even more rapid starts but cooks the clutch and strains the rear differential. At least private-sale cars give you the opportunity to meet the owner and gauge their level of hooliganism.

Features include electronic damper control (EDC), which offers three ride settings. The model was facelifted in 2007, when it gained smarter lighting and a mildly reworked cabin. The M6 coupé outnumbers the cabriolet by two to one. The drop-top’s hood is a complex, high-quality affair, but although the body is stiffened where it matters, ultimately the model lacks the coupé’s poise and bite.

Whichever bodystyle you’re tempted by, aim to buy the best-serviced and best-equipped one you can afford; one that stands out from the crowd. That way, you’ll make the most of the emerging interest in naturally aspirated motors such as the M6’s stupendous V10.

How to get one in your garage

An expert's view

Jack Day, Sutherland M Power Cars: “We buy and sell all types of M car but I can’t remember when we last had an M6 in the showroom. It’s the unreliable SMG gearbox that bothers people. It’s not like today’s twin-clutch transmissions. It’s a peculiar thing, and when it goes wrong, it can be expensive. Putting a warranty on the model is another big expense. And I’d be wary of the convertible for the extra complication it brings. On the positive side, the M6 is quicker than the M5 saloon, and although it’s not as practical, it looks fantastic. There’s a growing demand for powerful, naturally aspirated engines, too.”

Buyer beware...

■ Engine: Listen for valvetrain noise and grumbles from below, hopefully signalled by the engine warning light before terminal crank failure occurs. Check the service history for on-the-button oil changes, which conrod bearings, in particular, require. Inspect the throttle bodies and actuators. Expect a healthy engine to consume a litre of oil every 1000 miles.

■ Transmission: Even a sensibly used clutch lasts only 50,000 miles. (Check for the red cog warning light on the dashboard.) Expect the gearbox to be clunky around town but to free up with speed. A good one should pick up smoothly from rest and reverse without drama, although juddering may be a (relatively inexpensive) clutch release bearing and guide bush on its way out. Updated SMG3 ’boxes from 2006 onwards are more reliable than earlier ones. Whining and clunks from the rear diff are a no-no. Check it for oil leaks, too.

■ Suspension, steering and brakes: Juddering through the steering wheel may be worn control arms. Replacement dampers for the electronic damper control system are expensive (about £600 each). Check for worn pads and lipped discs. Beware aftermarket alloy wheels, which may be oversized and rubbing the arches. Check tyres are premium brands.

■ Body and interior: Check for water in the headlights and also in the cabin, which it enters via blocked roof drains. Problems with the hard drive can cause the iController to freeze on the BMW opening page.

Also worth knowing

Don’t downplay the significance of any warning lights. The MOT comes down hard on those, including the engine warning light and any deemed to be safety related, including brakes, tyre pressure sensors, airbags and stability control. Repairs could bankrupt you.

How much to spend

£9000-£12,499: Mainly early, private-sale cars around 100,000 miles optimistically priced but some with good histories and valuable recent work, including a 2005 car with 87,000 miles, full service history and new clutch and flywheel for £10,750.

£12,500-£13,999: Mainly lower-mileage 2006-07 cars with good service histories but, again, mainly private-sale examples.

£14,000-£18,999: Tidier cars with faultless service histories and around 50,000 miles.

£19,000-£21,000: Some exceptional, late-plate coupés and convertibles but also some merely good cars at strong prices.

One we found

BMW M6, 2007/57-reg, 51,000 miles, £16,495: This private-sale car (so scope for a price reduction) is the facelift model and has full BMW service history and an official BMW extended warranty. Nothing about it having had a new clutch and flywheel, which is reassuring, but get that price down.

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Comments
7

9 December 2019

garage would be a good place for these basket case type cars, only any good for the first owner (3-5 years) after that point you better be minted or have an alternative vehicle. Remember these are "prototype cars" at best full of stale tech that's now getting doddery and expensive to fix.

9 December 2019
How many of these expensive horror stories apply to a lesser engined 6?

9 December 2019

 Even if cash wasn't an issue, having to constantly shell out for wear n tear item, the fear that the SMG box could go pop at any time,and numerous other expensive things, I just can't see the point of buying one.

9 December 2019
Peter Cavellini wrote:

 Even if cash wasn't an issue, having to constantly shell out for wear n tear item, the fear that the SMG box could go pop at any time,and numerous other expensive things, I just can't see the point of buying one.

 

Petey and its alter ego xxxx, moan then present another reason why that particular car is not for them. No one can see the point of your posts, they contain nothing new or of any interest WHATSOEVER. Fool.

9 December 2019

These are basically 1-owner cars, the first owner, after that (when warranty has ran out) it is ready for the scrap heap due to horrendous maintenance costs. What a waste of resources...

9 December 2019

Just imagine it was made by Toyota. No one would want it because it would have the wrong badge. But i doubt it would have any of these reliability issues

9 December 2019
artill wrote:

Just imagine it was made by Toyota. No one would want it because it would have the wrong badge. But i doubt it would have any of these reliability issues

iThats the reverse of what there saying about the new Supra.....?

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