Mercedes-Benz SL-Class (2002 – 2008) Review

Check the operation of the roof.

Check the history of the car very carefully. If you are spending upwards of £30,000 you don't want to buy an SL with a chequered past.

On early SL350s and 500s the baffles in the fuel tank are prone to breaking loose and rattling, and it's a £1,500 - £2,000 job to replace the tank because it involves dismantling part of the folding roof mechanism.

Big bills for ECU problems, locking vacuum pump and transmission problems.

Warning sign indicating "electrics off line" and "battery", which disappears after a few miles means more than this. The electronic brakes could fail. Mercedes 24hour hot line, excellent service with a real mechanic can fix (needs a new alternator). BUT DON'T IGNORE THE WARNING.

Older cars develop a leak in the poorly designed seal at the rear of the roof that costs £2,500 to replace. If unrepaired, boots can fill up with water.

Auxiliary battery may not keep its charge for more than 2-3 days and thus i have no use of remote opening /roof down / heated seats / seat adjustments etc , all of which i understand are controlled by this power source , until the car has been running & charging the battery for 10 minutes + . This defeats the object of roof down in hot weather & heated seats in the cold.

'Least Reliable European badged 3 - 7 year old car' in 2011 Warranty Direct Reliability Survey, with a 47% incident rate and a £742.10 average cost of repair www.reliabilityindex.co.uk

Problem of premature wear of timing chain sprocket for balancer shaft of M272 and M273 V6 petrol engines. Mercedes Star bulletin about this. Big job. Can cost £4,000.

Moisture gets into the central locking vacuum pump affectiong its operation.

Issues with the seals of the folding hard-top, replacement of which is a two day £1,800 job. Corrosion has been found in the window frames while this was carried out.

Faults with a (now) 33,000 mile 2003 SL500 over the years: September 2007 15,000 miles airbag line fault, cost £630. January 2010 22,500 miles active body control unit fault £612. October 2010 26,000 miles catalytic converter replaced £950. October 2011 revealed the off side track rod end needs replacing £250. September 2012 33,000 miles: On return from a recent journey to Italy a new noise has emerged which is diagnosed as the power steering/ABC pump. The only solution being to replace it at a cost of nearly £2000.

Corrosion reported along the rear scuttle and in the leading edges of the flanges of both rear wheel arches of a 2003 R230. Mercedes dealer said not covered by 30 year Mobilo warranty.

Mercedes SL 2002-2009 rated 3rd most likely car built 1997-2009 to suffer expensive problems according to Warranty Direct December 2012 Reliability Index, with an index of 555 (compared with a rating of 6 for the best)

Mysterious electrical fault on 2005/55 SL350 purchased 2nd hand from an independent dealer deemed unrepairable by Mercedes dealer.

Report of boot seal failure on 34k mile 2006/56 car, costing £500 to replace, but leading to swamped electrics of ancilliaries pump in the boot compartment that cost £1,000 to replace.

SBC pump failed on 49,600 mile 2007 Mercedes SL350 and, despite some independent dealer involvement, Mercedes-Benz agreed to replace it free of charge.

Hydraulic central locking pump on SL55AMG failed for a second time within 8 months and 725 miles due to water ingress to load area. Question is, why didn't the dealer fix the leak when he replaced the pump?

Roof seals of 2007 Mercedes SL350 failed causing condensation inside the car and electrical damage. MB dealer has replaced them twice but they still fail and water continues to get into the car.

Another report of failed C pillar seal, on a 2006 SL350. Quoted as "Both lower/outer c-pillar seals detached, requires new. Cost £2,349.60." Apparently the seal was modified for the 2008 facelift. MB dealer told reader to "wait and see if you get water in the boot before doing it." Now he does have water in the boot. Local garage unwilling to undertake the work because of its complexity.

Report of problems with ABC braking system of 54k miles 2003 Mercedes Benz SL500. 'ABC visit workshop' (soft) warning light came on. Mercedes dealer replaced strut (£1,300). On collection car could not be driven from forecourt: red ABC warning. Dealer replaced tandem pump (£1,377). Four days later, soft warning appeared again. Later the same day f/os suspension collapsed: connecting rod broken. Repaired FOC. Car serviced/MoTs. Then needed to be returned because of clunking noise from steering on lock-to-lock when car stationary. Diagonal struts re-aligned (discounted cost £120).

Extensive corrosion found in area of the starter battery of a 2003 Mercedes-Benz SL600 when the battery was removed. It had been replaced in 2013 but the expansion pipe to channel acid away from the battery area had not been refitted, and the battery tray and inner wing had suffered extensive corrosion quoted at £7,000 to repair. (So this is an area worth checking if buying a used R230 SL.)