Originally Posted by Hatterasguy

They are very different cars.

These cars have whats called a 603 so you don't get more confused, and that 300D is a W124. Its a very good sedan in all respects, with a very good engine.

If you are DIY you will come to love MB's because once you figure out how they do things they are very easy to work on. MB does things different than the GM's you are used to so their will be a bit of a learning curve.

Anyway do a search on 603 and sit back with a drink and read. The largest problem is a potiental for the head to crack if you overheat it. Mine has near 270k miles on the original head and head gasket and doesn't burn a drop of oil or coolant, so to everyone who is afraid of them, bah!

Since its for your wife I would have her drive both the W124 and W126, to see what body she likes more. The W126 is a large car so a lot of people don't like them. However the W126 has a lot more room under the hood...

Oh and 603's certainly do have glow plugs and for some reason love being glowed, even when they are hot. Skip the glow cycle and they will start like crap.

These are not slow cars, any example should be able to do 0-60 in 10-12 seconds, a lot of them are down on power because people don't take the time to tune them, usualy low power is a very simple to fix.