The W126 Mercedes 4-door sedan was in production between 1979 and 1991 and was later joined by a coupe version as well (1981-1990). The W126 is the second generation of the iconic S-Class and it was also the very first S-Class to benefit from separate chassis codes for the extended wheelbase model and the standard model.
The early 1980s are known for the oil crisis which shifted the automotive industry towards a more efficient and sustainable future. This meant that even the S-Class had to adapt to a more economical market which meant smaller engines and an overall lighter automobile.
The W126 came in a few different engine options, starting with a 6-cylinder M110 engine that was carried over from its predecessor, the W116. The W126 also came with a few V8 options which are nowadays a lot more popular because almost everyone believes that an S-Class deserves a large displacement engine.
All in all, all the engines found in the W126 are durable and should last you hundreds of thousands of miles without needing major overhauls. The most common issues with the W126 are oil leaks and timing chains issues, and the overall body and chassis are indeed durable but are also prone to rust if not protected.
Mercedes W126 – The powerplant
As previously mentioned, the W126 came in a few different engines and the entry-level W126 offered a 2.6L 6-cylinder with 156hp. This engine is relatively reliable and is the most fuel-efficient of the bunch, but it is not the most popular engine these days.
The W126 also comes with a 3.0L 6-cylinder that offers a more potent 180hp and it was more or less the same as the 2.6L. If you want an 8-cylinder W126, you had to upgrade to the 380 model with offers a 4.0L V8 with 200hp while the 420 model offers a 4.2L V8. Both of these engines are reliable and more fitting for an S-Class.
However, the best engine you can go for in the W126 is the 5.0L V8 found in the S500. This engine offers an adequate 231hp and is now considered to be the most desirable engine of the bunch. The range-topping W126 came with a 5.5L V8 with 300hp in the S560 which is also a popular engine these days.
All W126 models are RWD and are available with either a 5-speed manual for the smaller displacement engines or a 4-speed automatic which was the only option for the V8 models.
Mercedes W126 – Design and body
The W126 was the first S-Class to utilize a more comprehensive rust protection technique which meant that the W126 was not as prone to rust as the W116 model. However, the W126 is more than 40 years old now which means that finding rust spots is almost inevitable.
The area around the rear windshield is known to rust on most W126 models, but regular places such as under the door or inside the wheel wells are also prone to rust. Either way, you should carefully address the entire underside of the car and all the window surroundings and suspension components for any signs of rust.
The design of the W126 is more of an evolution than it is a revolution over the W116 which means that it is still a similar-looking car. However, the W126 incorporated a few more modern design touches which made the W126 more refined and more sophisticated-looking.
Mercedes W126 – Common issues and reliability
The W126 is a fairly reliable car that should last you a long time if you address all the common issues in due time. The most common W126 issues are associated with the plastic guides situated on the timing chain which are known to crack from time to time.
The W126 also suffers from head gasket oil leaks and potential oil leaks near the timing chain. Issues such as these need to be addressed in due time because they are likely going to become worse in the future. The W126 also suffers from being a 40+-year-old car which means that the interior is not as sturdy as it once was.
Mercedes W126 – Value and practicality
The average asking price for a W126 in decent condition is around $20,000, but the higher-end V8 models often sell for twice as much if they are in good condition. The W126 is slowly creeping up in value because there aren’t many of these left in good condition.
Practicality-wise, it is more or less the same as a modern-day C-Class or E-Class. The interior space is decent for average-sized adults and the cargo area is more than enough for 99% of people.
Is the W126 the best S-Class of all time?
The W126 S-Class is not the best S-Class of all time because that honor goes to the W140. However, this does not mean that the W126 is a bad car, quite the contrary, the W126 is actually a great car, but it is rather difficult to compare it to the W140 which is a true automotive icon.
The W126 shares many benefits with the W140 such as innovative design choices, new technologies, and features, an incredibly plush ride for its time, and a plethora of reliable and potent engines.
Is the W126 going to appreciate in value?
Mercedes says that they delivered more than 800,000 W126 models through its years in production. This means that the W126 is not exactly rare, but it’s not as common as some Mercedes models are. For a spot of context, Mercedes managed to deliver almost 2 million 190E models.
As such, if you are able to buy a W126 with a V8 and in decent condition, you are likely going to profit from it in the future. No one can say for certain which cars are going up and which ones are going down, but there is quite a bit of interest in the W126.
Can I use the W126 as my daily driver?
The W126 can be used as a daily driver, but you are not going to be able to profit from all the modern-era technologies you are used to. The W126 is rather large and it does not offer all that much to keep you entertained besides the looks and the feel.
Safety-wise, the W126 is good, but only from a 1980s point of view. That being said, it’s best to use the W126 as a weekend cruiser or a car for special occasions, especially if you are a family man.