cgranju - It's a good question. Some good points made here.

I think they are both good engines, the key is maintenance. How have they been serviced? If you find an M112 that has had frequent oil changes, either more than stipulated by FSS or at least on par, and has also used ONLY approved synthetic oil, it should prove a fine engine. I would not purchase one without this service record documentation in hand.

There seem to be quite a few ML owners with M112s that use oil, and have been serviced well. So it does seem that some of these engines use oil, whereas this was not an issue with the M104. Definitely something to consider. As stated, my M113 uses oil and it is a frustrating issue to try and rectify as diagnosis is very difficult - short of tearing the entire engine open.

However, the 722.6 transmission is leagues beyond the old 4-speed in terms of performance and quality of ride. If you bought a 1999 model, you would probably be in good stead in terms of getting a solid specimen.

Then there is the 1997 E320, which will give you the M104 and the 722.6. A family member here has this car and it has proved very reliable and durable. Now close to 160,000 Km, it has the original tranny and engine. Not a single problem with either (doesn't burn a drop of oil either). We have had the transmission fluid changed however, and will do so every 50,000 Km - Mercedes' 'lifetime' fill be damned.

Good luck!

__________________
Chris
2007 E550 4Matic - 61,000 Km - Iridium Silver, black leather, Sport package, Premium 2 package
2007 GL450 4Matic - 62,000 Km - Obsidian Black Metallic, black leather, all options
1998 E430 - sold
1989 300E - 333,000 Km - sold
1977 280E - sold
1971 250 - retired

"And a frign hat. They gave me a hat at the annual benefits meeting. I said. how does this benefit me. I dont have anything from the company.. So they gave me a hat." - TheDon