Which is better, Mercedes Benz W123 or W124 in terms of reliability, comfort, and maintenance

W124 is far more comfortable than W123. More power, quieter, better handling, & over-all, better vehicle. You should be aware, the newest W124 is 1995 model, where as newest W123, l think is 1986 model. They r 13 years old & 22 years old respectively. (assuming u get the last model)

Please be sure u can afford the maintenance! W124 has well known issues such as wiring harness rotting away causing need for harness replacement, & throttle actuator replacement. They will cost u about 1500 dollars each, if u need it. Also, the M104 engine used on later model has a tendency to leak from head gasket. It will run u about 1800 dollars to do the work.

W123, because of age, anything can break at any time. Most W123 r Diesel models. If turbo goes or emission system goes (which is kind of known to happen), they will cost u quite a bit. Most of them has well over 200K miles.

the 124 is better in every way because it is newer. its more reliable, safer, might have less maintenance, more comfortable.

I've owned both, & they were both great cars in their day. But it is been a long time from Stuttgart for anything still on the road. You have to evaluate the cars that r available to u today.

If u could have them both from new, the 123 was probably the most over engineered car ever built. It is rugged, reliable, & very repairable. The 124 was also overdesigned, & is similarly reliable. There r a few exceptions, like the wiring harnesses on the very last cars, but a good 124 will go as far as a good 123, & be about the same to maintain. A 124 would be a bit more up-to-date as far as creature comforts: better climate control, better stereos, etc. l think that Mercedes transmissions were much smoother shifting after about 1987. Given the choice of either in like new condition, I'd probably lean to the 124. But a cherry 300CD would be hard to resist.

Perhaps my 2 most favorite Mercedes of all time r the 300D w123 chassis & the E320 w124 chassis. While both cars can last a VERY long time, I'd have to say that the w124 was much more comfortable to drive. It is still very easy to repair, when necessary. If u could find a 1987 e300d with the 6cyl diesel, then u certainly have a million mile car. The engine is nearly bullet proof & the updated transmission was much more reliable than what the w123 is had in them.

Also, the stereo system in the w124 was a big improvement over the w123. Power seats, better cruise control module, more efficient A/C system & more structural rigidity. Geez, l think l will go & look for one on Craigslist tonight! I've talked myself back into one again!

Actually, l do own a very nice 1984 300D & love it dearly. If l could find a w124 with the diesel 6 in it, I'd sell it in a heartbeat.

So, that all being said, go for the w124 & be happy no matter what engine u purchase. Just stay away form the v-8's. Not nearly as reliable as the 6's.

Hope this info helps.

the W123 might not require coslty maintenance but l would go with the W124 comfort and performance way better.

Parts are cheap for both vehicles and maintenence can be self done. These cars are very straight forward to work on. l never cared for the look of the 123, but was a very reliable, bomb proof vehicle. l have always enjoyed the style of the 124 body, especially with the m104 motor, very smooth runner. l do not recall any wiring issues with either of these models, that came later on the 202 and 210 bodies.