AMG is the high-performance division of Mercedes-Benz and has produced some blisteringly quick sports cars, but some are better than others.
Thumping great V8s, turbocharged V12s and thunder-stricken soundtracks are just some of the rewards that await future AMG customers, but not all routes into ownership of these German brutes are as safe as the rest. As with all performance cars, some have hideously expensive repair bills and troublesome common faults that will put off all but the bravest prospective purchasers.
AMG, the high-performance division of Mercedes-Benz,have a superb back-catalog to choose from, and we’ve done the work for you researching some of the favorite models and picking out which will leave you smiling, and which will leave you reaching into your wallet. So, pay close attention if you’re contemplating stepping into any of the cars below.
10 Unreliable AMG Model: 2008 C63 AMGBring a Trailer
A modern icon, and for most gearheads, possibly the first car that springs to mind when the letters ‘AMG’ are muttered – the infamous C63. With a production run that spanned not far off a decade, with many iterations introduced such as the 507 and black series, it’s a well-loved model with a dedicated fan base – fans who are willing to look past the ugly common faults that plague these European muscle cars.
Early examples suffer from rusty head bolts, which of course then break and lead to all sorts of issues (namely head gasket failure), which of course can vary from uncomfortably expensive to outright extortionate if not caught in time. It’s no surprise, then, that the earlier models are so affordable to purchase now. If you are considering one, take a good look through the service history and have it thoroughly inspected to ensure this nasty issue doesn’t catch you out.
9 Mercedes-AMG Model That Will Last A Lifetime: 2011 SLS AMGBring a Trailer
The SLS was fully designed and manufactured by AMG in-house, meaning they had full control over the quality and standard of the final product. With so much at stake, ensuring that AMG didn’t disappoint with the launch of their new supercar, everything was done to the highest standards, and it shows.
The gullwing endowed body houses a 563 hp V8 which is capable of a seriously impressive 0-60 mph time of just 3.8 seconds, and it will continue all the way to 197 mph, if you’re bold enough to keep your foot in it. This special sports car is a great alternative to the obvious Italian choices too, and will beat them every single time when it comes to reliability.
8 Unreliable AMG Model: 2006 ML63 AMGBring a Trailer
To start off with, the ML63 AMG also suffers with the same rusting head bolt issue that earlier C63 models experience, so before we even dive into the specific common faults with this car, there’s already the risk of head gasket failure and expensive preventative maintenance.
Like so many other performance SUV’s, the ML63 also discovers that a whopping great 510 hp V8 shoe-horned into a cumbersome, near-5,000 Ib body puts excess stress onto the inner workings and mechanical components. For example, the steering rack is a common weak point on these, and NHTSA has over 200 customer complaints logged.
7 Mercedes-AMG Model That Will Last A Lifetime: 1999 E55 AMGBring a Trailer
Winding the clock back finds us looking at the E55 AMG. Almost a sleeper from the factory, the W210 iteration of this ever-popular sports sedan looks very unassuming, but packs a powerful punch with a 349 hp naturally aspirated V8 developing 390 Ib-ft of torque.
This E55 harks back from an era in which Mercedes were world renowned for the reliability of their products, and rightfully so, as every component was over-engineered and built to last on these old school autobahn thrill seekers. From hardy interiors to strong mechanicals, the E55 was built to last from the beginning, and the fact that so many remain in great health is a testament to the great endurance and reliability of these cars.
6 Unreliable AMG Model: 1997 C36 AMGBring a Trailer
Unfortunately, not all Mercedes products from this era can claim they were built to last, and the original C36 AMG is one of the unfortunate examples. Being the first C-Class model which had the AMG treatment as a factory offering, it was an exciting sedan which had a lot to offer while retaining all the usual features and gadgets you’d expect from a luxury European car of the era.
AMG did a great job, too, equipping it with a 276 hp 3.6-liter inline-six that sounds fantastic winding up through the revs, and performed great on both highways and through twisting back roads. Unfortunately for the C36, Mercedes did not do such a great job on the bodywork, as these W202 models were incredibly rust prone, meaning unless you’re keen on spending thousands of dollars on welding or keeping your sports sedan locked away in all but dry weather, this era C-Class is certainly not built to stand the test of time. No surprise, then, that they are worth far less than the equivalent M3 of the same age.
5 Mercedes-AMG Model That Will Last A Lifetime: 2019 AMG GTCMercedes-AMG
Until recently, if you wanted a sporty drop-top from Mercedes, you were fairly restricted to the long-standing SL-Class or smaller and more approachable SLK, neither of which could really be classed as driver focussed sports cars. The AMG GTC then is a warm welcome for fans of Mercedes, offering a proper sports car experience with all the usual refinements and luxury you’d expect from the brand.
What’s more, the AMG GTC has been developed from the ground up and was subject to much performance testing pre-production. This means not only does it leave behind any common issues from preceding models, but it also had any annoying foibles ironed out, long before any examples hit the showroom floor.
A well-developed and thoroughly enjoyable sports car, the AMG GTC is here to stay and will last a lifetime if properly maintained and serviced.
4 Unreliable AMG Model: 2006 SL65 AMGBring a Trailer
While we are on the topic of the performance efforts of AMG on convertible Mercedes models, let’s take a closer look at the SL65 AMG, which notably features a simply gargantuan twin-turbo V12 with a 6.0-liter displacement and over 600 hp on tap – enough to catapult this outrageous supercar slayer from 0-60 mph in 4.1 seconds.
As usual then, it’s clear to see that AMG did a pretty impressive job, but sadly once again the tuning house team have been let down on the reliability side from the folks at Mercedes, who have left some major oversights in the base model. Primarily, the major issue with this era SL is the roof motor packs in, commonly due to water ingress, which as you can imagine is an expensive repair on a high-end Mercedes.
In addition to this, the V8 and V12 models of the SL featured hydraulic self-levelling suspension, which can often fail. Unfortunately for current and prospective owners, these air struts are around $1,500 fitted each, meaning quite often the SL65 can be left sitting with expensive repairs being put off.
3 Mercedes-AMG Model That Will Last A Lifetime: 2019 C43 AMGMercedes
Mercedes and AMG have teamed up to produce a C43 once before. However, this newer model is a much more complete and well-rounded product. Sleek and stylish with a performance focussed drivetrain, the C43 may just be the perfect daily driver.
How do we know it will last a lifetime, though? This model was developed to handle all the power and stresses of its big brother, the C63, with a 503 hp V8. However, the C43 makes do with a more than adequate 385 hp 3.0-liter V6 biturbo, meaning all the components are well under their stress threshold, and are unlikely to fail. The perfect middle ground between a sensible C300 and crazy C63, there’s a lot to love about the C43 AMG.
2 Unreliable AMG Model: 2007 R63 AMGBring a Trailer
There have been many crazy creations over the years that have somehow made it through the AMG factory doors, but this one surely tops them all, landing somewhere between bonkers and just downright unnecessary. The R-Class was poorly received in standard guise anyway. Being the ugly step-sister of the SUV range, the R-Class was the minivan that nobody asked for.
Not only is it cosmetically challenged, but the R63 also suffered from all the usual rusting head bolt issues that we’ve become accustomed to in this list. In addition to failing catalytic converters and excessive oil consumption, the R63 is just too expensive to maintain and the end product of owning one is not worth the trouble – this is one unreliable experiment that’s better left in the history books.
1 Mercedes-AMG Model That Will Last A Lifetime: 2001 SLK32 AMGBring a Trailer
An often forgotten and overlooked model from the AMG wheelhouse is the diminutive R170 SLK, and with a great engine under the hood and nimble handling, it’s certainly time this two-seater convertible was reconsidered, and given the appreciation it deserves.
The 3.2-liter V6 has been supercharged and develops a healthy 350 hp, plus these models have proven many times they are capable of some serious mileage, showing us they are not just fun to drive on sunny weekends but also built to last a lifetime, and more than happy to endure some daily duties.
Both in automatic and manual guise, the drivetrain is bulletproof on these low stress convertibles, and so long as you keep on top of regular servicing and maintenance this cut-price AMG should keep going for years and years, proving they’re not all unreliable and don’t need to cost a fortune either.