Since their debuts, both the C43 AMG and C63 AMGs have built up their reputations as two of the hottest cars in the Mercedes lineup. Initially, the C43 caught a lot of flack for its perceived lack of power, but it has changed critics minds with its deft handling, impeccable performance, and luxurious interior. The C63 AMG, on the other hand, has always wowed drivers with its impressive power delivery and smooth handling.
The C43 has always been thought of as the little brother of C63, and it’s a fair comparison. The C63 is more expensive, about $10,000 depending on options, yet it is a whole lot more powerful. Mercedes added 84-107 horsepower and 99-131 torque between the C43 and C63/C63 S AMGs.
Unfortunately, emissions regulations forced Mercedes to discontinue both models in 2021-22. However, both the C43 AMG and C63 AMG are thankfully set to return for 2023 after undergoing some huge changes. Mercedes has officially announced the C43, but the C63 is still in the final stages of development. They will both ditch their previous motors to receive 2.0L inline-4 engines, supplemented with electric motors and electric turbos.
The following guide will look at the history, engines, common problems, and performance of the C43 and C63 AMGs. First, let’s take a look at the history and performance of both cars over the years.
Mercedes C43 vs C63 AMG History & Performance
The Mercedes C43 AMG first became available back from 1998-2000, before being discontinued from 2001-2014. It returned in 2015 as a completely new car, featuring a new AWD drivetrain to replace its former RWD layout. On the other hand, the C63 AMG was available continuously from 2008-2021, always with RWD. Reviewers and critics have extensively reviewed both models, and the widespread consensus is that Mercedes nailed the balance between performance and luxury. The C63 has always boasted superior performance to the C43, but both are capable of neck-snapping acceleration when needed.
W202 (1998-2000) C43 AMG
From 1998-2000, the M113 engine, a 4.3L naturally aspirated V8 tuned by AMG, powered the first generation C43 AMG. It featured forged rods, newly developed oil jets to cool the pistons, twin-tube air intakes, and modular camshafts. Yet, impressively, Mercedes claimed that it still performed as an Ultra Low Emission Vehicle. At the time, it was second only to the S600 in terms of speed in the Mercedes lineup.
The W202 C43 AMG made 302-hp and 302-tq, and connected to a 5-speed automatic transmission that powered the rear wheels. Solid for its time, it went from zero to 60 mph in 6.1 seconds, and could make a ¼ mile pass in 14.7 seconds at 98 mph. It has stood up reasonably well over the last 20+ years, though critics have repeatedly noted the stiff suspension. Interior wise, the cabin is simple and elegant, yet refined, if not a little small.
W205 (2015-2022) C43 AMG
When the W205 C43 AMG returned in 2015, Mercedes initially branded it as the C400 4MATIC with no AMG designation. Mercedes again rebranded it the following year, this time as the C450 AMG. It featured the same engine, and was nearly identical but with slightly revised styling. Finally, in 2017, Mercedes returned the C43 AMG designation, as well as the coupe and cabriolet options.
The C43 AMG has the same engine from 2015-2021, the M276 DE 30 LA, a 3.0L biturbo V6. From 2015-2018, the M276 made 362-hp and 380-tq, and that was bumped up to 385-hp and 385-tq for 2019-2021. All years connect to a 7-speed automatic transmission pushing power to all four wheels. Previously, we looked at common problems with the M276 series of engines, so make sure to check that out.
The W205 C43 AMG goes from zero to 60 mph in 4.5 seconds and hits the ¼ mile in 13.1 seconds at 108 mph – substantial improvements from its late ‘90s predecessor. While drivers note the incredible handling and performance of the C43 AMG, they criticize its overly firm suspension (again). In earlier model years, critics also noted the outdated infotainment system and lack of standard options.
W206 (2023+) C43 AMG
The C43 AMG is returning for the 2023 model year with a brand new hybrid-electric drivetrain. Mercedes combined the M139 2.0L inline-4 with a 48v hybrid electric starter-generator system. The M139 makes 402-hp and 369-tq, with the hybrid system capable of adding an additional 13-hp. The M139 is also the world’s first production engine to utilize an electric turbocharger. The electric turbo reportedly uses technology adapted from the Mercedes-AMG Petronas F1 team.
A 9-speed automatic lays down power to all four wheels through Mercedes patented 4MATIC AWD system. It also has adaptive suspension damping to aid with comfortability while riding around town. Initial tests have the C43 sprinting from zero to 60 mph in 4.3 seconds, and doing the ¼ mile in 12.4 seconds. Reviewers acclaim the C43’s incredibly snappy performance and minimal turbo lag, while continuing to criticize the harsh and stiff suspension.
W204 (2008-2014) C63 AMG
For the W204 C63 AMG, Mercedes put the M156 engine. It is a 6.2L naturally aspirated, quad cam, silicone-aluminum block, V8, and produced 451-hp and 443-tq in the C63. It was highly sought out for its excellent power, large power band, and ungodly sound. The W204 C63 AMG went from zero to 60 mph in 4.5 seconds and could do the ¼ mile in just 12.1 seconds at 117 mph. All years had a 7-speed automatic transmission driving power to the rear wheels. Previously, we looked in-depth at the M156 with our engine guide, so make sure to check that out for the full rundown.
Mercedes made a performance package available for the W204 C43 AMG that raised power by 30-hp, featured forged internals, and increased the top speed. In 2012, it got a facelift, which included a revised grille and front fascia, along with new LED lighting. A limited-slip differential was also optional, and really helped put the torque down to the wheels. Drivers consistently praise the W204’s suspension and handling, noting that it is firm but not harsh, and takes corners with aplomb.
W205 (2015-2021) C63 AMG & C63 S AMG
In 2015, Mercedes released the second generation of the C63 AMG, the W205, which now included the high spec C63 S AMG. AMG upgraded the car’s engine to the M177 DE 40 LA, a 4.0L biturbo, 32 valve, aluminum block, V8. The M177 has twin BorgWarner turbos that produce 469-hp and 479-tq in the standard C63 AMG, and 503-hp and 516-tq in the S.
These AMG tuned mammoths can blast from zero to 60 mph in 3.8 and 3.7 seconds, respectively, and they can do the ¼ mile in 12.0 and 11.9 seconds at 122 and 123 mph. The W205 carried over the same 7-speed transmission until 2018, when Mercedes replaced it with a new 9-speed automatic. Both transmissions fed power to the rear wheels and with optional limited slip differentials (standard on the S).
Moreover, critics lauded the exceptional chassis response and responsive handling of the new W205. In 2019, Mercedes gave the C63 and C63 S AMGs a facelift, which included a larger infotainment display, new color options, slightly revised styling, and made several safety features standard.
Mercedes C43 and C63 AMG: Common Problems
Now that we have looked at the history and performance of the C43 AMG and C63/C63 S AMGs, let’s talk about their issues. Overall, both the C43 and C63 AMGs are relatively reliable cars that do not suffer from any major problems. The big exception is for early versions of the M156 engine, which we will cover below. They are far from problem free or bulletproof cars, so let’s look at some of the issues they each can suffer from.
W202 C43 AMG Common Problems
The W202 C43 AMG has been around the longest of any model in this guide, and thus has the most data on its reliability. The M113 V8 engine overall is pretty stout and does not suffer from any major issues. However, the rear main seal for the crankshaft is prone to leaking, and the dual-spark plugs have been known to burn out exceptionally quickly. Previously, we have covered the most common problems with the M113 engine, so make sure to check that guide out.
The W202’s suspension, on the other hand, has not held up nearly so well over the past two decades. Control arms and bushing are common items that need upgrading and replacing by this point. Quite frankly, the rest of the suspension should really be checked out pretty good to make sure everything is still tight and functioning properly. There have been many reports of suspension components and bushing wearing out completely on high mileage W202 C43 AMGs.
The automatic transmission is also prone to a lot of issues, both with high mileage and when adding extra power. Many C43 AMG drivers report serious transmission issues after 75,000-80,000 miles, often requiring full rebuilds. Modding the C43 AMG also brings transmission issues, as they struggle to keep up with the extra torque.
W205 C43 AMG Common Problems
The W205 C400 4MATIC, C450 AMG, and C43 AMGs are all much newer than the late ‘90s models, and thus are much more consistently built and engineered. Still, users have reported lots of excessive rattles and squeaks, especially along the doors and dashboard, as well as various electrical issues.
The 7-speed transmission is also the subject of a lot of complaints. Drivers criticize its jerky shifting out of 1st and 2nd gears from a standstill, and many people have reported loud bangs and pops coming after excessively uncomfortable shifts. Many have reported transmissions needing to be rebuilt, however, and computer software updates have solved the issue in several cases.
The M276 V6 engine, like its V8 predecessor, is also an engine with above average reliability. However, there are small issues relating to the high pressure fuel pump, carbon buildup from the direct injection, timing chain tensioners, and the spark plugs and coils. Check out our guide on the top M276 problems for a more elaborate breakdown of these issues.
Overall, the W202 and W205 C43 AMGs are above average in terms of reliability, though abused models are certainly prone to more issues. High mileage W202s should be thoroughly checked over suspension wise to make sure everything has been properly maintained and is still in good shape. Drivers have not reported too many problems with the W205, though there are not a ton of high mileage examples.
W204 C63 AMG Common Problems
The biggest issues on the W204 C63 AMGs are related to early models with pre-2011 versions of the M156 engine. Overall, the engine is pretty reliable, but there were serious problems with the head bolts and valve train. Mercedes poorly designed the pre-2011 M156 head bolts and they were easily prone to leaking and breaking. People regularly expressed issues with coolant loss and eventual engine failure due to head bolts. The valve train also had issues with the cam adjusters, cam lobes, and lifters. They were all, again, poorly designed and prone to lubrication and oil starvation issues as well as considerable premature wear.
Previously, we looked at the M156 engine in our guide, so make sure to check that out for more information.
The 7-speed transmission is the same from the W205 C43 AMG, and drivers criticize it in the C63 AMG, too. The main complaints outside of the powertrain are with consistent squeaks and rattles throughout the car. Drivers constantly complain about squeaking with the dashboard, climate control knobs, sunroof, brakes, doors, and mirrors. Some of this is just due to poor build quality, and in some cases it is from loose screws or poorly applied adhesive glue. Luckily, these are relatively minor complaints, but they do tend to feel outsized when you just spent $60,000 on the car.
W205 C63 AMG Common Problems
Overall, the M177 DE 40 LA that powers the W205 C63 AMGs is a pretty reliable and stout engine. The main issues are related to misfires, and drivers have reported problems with both spark plugs and coil packs. They seem to go out very quickly and it is not entirely clear why. Part of it is likely from the gargantuan performance of the M177, producing 469-503-hp, burning through spark plugs too quickly.
Similar to the W204 C63 AMG as well as the C43 AMGs, there are a lot of complaints about rattles and squeaks on the interior. The main areas are the dashboard, brakes, doors, and rear suspension. The intake manifold is also prone to leaking due to poor design.
Similar to the W204, these are all relatively minor items, but with a car that costs as much as these do, they become harder to ignore. Mercedes generally has pretty good build quality with their cars, but they seem to have missed the mark on a lot of C63 AMGs.
Mercedes C43 vs C63 AMG Summary
Overall, the Mercedes C43 and C63 AMGs are enjoyable and fun cars that truly live up to the AMG name. The C43 has come a long way since its late 1990s version, improving in just about every way imaginable. The C63, on the other hand, was already on the cutting edge of modern luxury and tech from its 2015 inception, and it has only continued to maintain its already high expectations.
Performance wise, the C43 AMG really can’t compete with the C63 AMG, but they are both fun in their own ways. The C43 AMG is more family oriented, with softer suspension and more manageable power. Also, its 4MATIC AWD drivetrain is a huge boost for those living in places with extreme rain and snow. The C63 AMG, on the other hand, still delivers luxury and comfort, but in a much more powerful package.
The price difference, surprisingly, is not as drastic as you might think. The C43 AMG comes in about $10,000 cheaper than the C63 AMG on average, of course depending on options. That’s not an insignificant decrease by any means, but for the sacrifice in performance it’s hard to justify. However, for those needing AWD, the C43 AMG is the only choice.
So far, Mercedes has only announced the specs for the 2023 C43 AMG. The C63 AMG still in development as far as we know. It will be very exciting to see where Mercedes goes with the hybrid-electric powertrain in the future, and it has already proven to be just as capable in delivering power.
What experience do you have with the C43 or C63 AMGs? Do you own one or are you thinking about purchasing one off the used market?
Let us know in the comments below!