The Mercedes 450SL was in production between 1972 and 1989 which made it the second longest-running single model in Mercedes Benz history, right behind the Mercedes Benz G-Class. The 450SL uses an 8-cylinder engine in various displacements which are decent when it comes to reliability.
It’s safe to say that the 450SL is fairly dependable, but after almost 50 years of life, cars such as these are known to develop all sorts of problems. The biggest and possibly most dangerous issue that plagues these cars is corrosion so be sure to check all the vulnerable spots before you do anything with the car.
The 450SL also suffers from issues associated with the subframe, cooling system, engine timing, and issues with worn-out mounts. However, given the fact that the 450SL is so old, chances are that you will encounter many issues down the line.
The best thing you can do is find an example that has been very well kept throughout the years, even if it costs a lot more money to begin with. If these were maintained throughout the years, it means that they are likely going to last a long time. If they weren’t, they are ticking time bombs.
Mercedes 450SL – Corrosion
The Mercedes 450SL is known to suffer from rust as is the case with many older Mercedes models. Either way, you should focus your attention on newer 450SL models as they use higher quality steel while the very latest post-1986 models even benefit from galvanized steel which offers the best corrosion protection.
The most vulnerable rust spots are the body sills, around the headlights, the trunk, the doors, the underside of the car, the front subframe, wheel arches, bumpers, around the sunroof, the hood area, and lower side skirts. Fixing a rusty car is incredibly difficult and time-consuming which means that it only makes sense to do so on a really valuable car.
Mercedes 450SL – Subframe issues
The Mercedes 450SL is also known to suffer from common front subframe issues in which the frame starts cracking after a while. These issues are particularly common with older models as they were not built all that sturdy. You can only imagine what would happen if the subframe completely cracked, so always keep an eye out on these.
Many older 450SL models now have replaced subframes with aftermarket ones which are made with higher standards of production. All in all, if you sense the car has loose steering, chances are that the subframe is to blame. Don’t drive the car as an issue such as these could easily end up in an accident.
Mercedes 450SL – Engine timing issues
The timing chain in the 450SL is tasked with synchronizing the valvetrain and the crankshaft in order for the car to run as intended. Even though the engines on these 450SL models are fairly sturdy, lackluster maintenance made them prone to issues with the timing chain.
If these do come to play, you will have to replace the chain completely. If you sense the engine is hesitant, misfires, or even stalls, your chain is likely the one to blame. Be sure to solve these issues as soon as possible, otherwise, the chain could potentially cause all sorts of damage to the engine.
Mercedes 450SL – Cooling system issues
We are already aware that the 450SL comes with big and powerful engines which means that these emit lots of heat. The cooling system on the 450SL is actually fairly decent, but the engines require a lot of cooling as well. This means that if the coolant levels are low or if the radiator is slightly clogged, your engine is going to overheat.
Issues such as these can typically be solved with timely maintenance so they are not that all that much problematic. However, as most of these were never maintained all that well, issues such as these are becoming more common and common.
Mercedes 450SL – Worn out mounts
The 450SL is an old car which means that it suffers from good old wear and tear. Some components are more problematic than others which means that they require more maintenance than usual. These components are engine mounts, transmission mounts, and rubber subframe mounts.
All of these are common wear and tear components on the 450SL which means that they can also be remedied with timely and thorough maintenance. However, we have already stated that not many of these were maintained correctly which could lead to these failing after a while.
Is the Mercedes 450SL worth it?
It depends on how the car has been maintained throughout its lifetime. Don’t be fooled by a low entry price, and don’t think that a $12,000 450SL is going to be cheap to run by any means. The only way for this car to make sense is to buy one with a well-documented history and one that has been kept in optimal condition for decades.
Maybe if you are a mechanic yourself and you know your way around classics, you could buy a higher-mileage, gazillion owners 450SL with no service records at all. However, if you are a mere mortal, you should avoid buying the 450SL if it’s not in good condition.
Why is the Mercedes 450SL so cheap?
Many people are wondering why the 450SL does not cost as much as some other classic cars from this era. After all, the 450SL looks great, it is a convertible, is fairly reliable, and uses big and exciting engines. It’s uncommon for cars such as these to not be extremely desirable and valuable, but why is the 450SL so cheap?
The reason being is that there are simply too many of these. We have already mentioned that the 450SL is one of the longest-running single models in MB history which means that supply is much higher than market demand.
Which Mercedes 450SL model year is best?
According to most Mercedes enthusiasts, the 1972 450SL is the best because it does not come with those ugly front and rear bumpers. The 1972 is a true classic when it comes to design, but it is not the best one when it comes to reliability.
Older 450SL models, such as the 1979 or the 1980s models are much better when it comes to rust which is the worst enemy of an old Mercedes.