I am looking at a W140 1993 300SD with the 3.5 liters Inline 6 engine (#603.971). I would like to know if this engine may have the same connecting rods problem as a '91 W126 350SDL (engine #603.970)?

Was 603.970 the only 3.5 engine affected by the problem?

Thanks,
HDenDiesel

__________________
W126 1985 300SD TurboDiesel
W164 2009 ML320 BlueTEC (Sold)
W123 1983 240D Stick (Sold)
W210 1998 E300D TurboDiesel (sold)
W124 1993 300D 2.5 Turbo (sold)
2012 GMC 2500 Duramax PickUp
2015 Ram 1500 EcoDiesel PickUp

HDenDiesel,

Besides the modifications needed to have the engine fit the W140 engine compartment, the engines are pretty similar. There were other modifications made to the innards over time but I do not think these are the source of the revised model number. So, the W140 3.5 liter TurboDiesels were also "rod benders" from the factory. At the end of the production run it is rumored the problem with rod bending was solved, as well as some other internal head and block weaknesses. It is also rumored a new or factory rebuilt version of that engine today is "cured" of the rod bending affliction.

I have never been able to get a straight story on exactly what has been changed to cure the problem and why it worked. So, since I experienced the problem first hand on a 1991 350SD, at 162,000 miles, I am not even tempted by the later models with supposed cures applied. I am also not impressed with the poor reliability record of the W140 "standard" gadgetry, or the cost of fixing things like bad air conditioning evaporators and the like. So a 3.5 liter TurboDiesel mated with the most unreliable "S" body sounds like hellish odds for a bad Mercedes-Benz experience. But there are some board members that have had these cars and loved (or still do) them.

Good luck, and I hope this helps, Jim

__________________
Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)

Do not buy a gas or diesel W140 chassis, they are pieces of crap!

My father in law bought a 400sel-92' and they have had problems with AC-$3500, Power Windows-$500, $500Headlights, Radio$500, Heater-500, etc... All in all the motor and tranny has held up great, even with poor maintenence! It's the electronics that have major problems. If I bought a W140 it would be the gas

My financial advisor-long term mb diesel owner 240d-300k, 300sd 350k, 300sd 170k and counting has had his problems with his W140 diesel. He has had the top end of the motor replaced at 60k, had the bottom end replaced at 150k to the tune of 4k. Has also had never ending problems with electronics.

I have not heard of anyone having good luck with these cars, and to top it all off since they have so many electronic gizmos you have to take it to a MB Stealership to get it fixed.

Sorry to rant, but I was the one who told my father in law to buy the 400sel 5 years ago, I will never hear the end of that one

I guess that goes for every single W140 chassis car that MB ever produced.

Unless they changed their entire electronic system, which they didn't, then I not would buy any W140-my mechanic agrees whole heartedly after seeing his customers dish out 1000's.

HDenDiesel
How do you like your Cummins?

Sounds like a great mechanic! Most others would encourage buyers if they would get that kibd of work.

My mechanic is definitely a differnent breed. He even helped me with a complaint that I had with Lexus.

Thanks for all your comments.

asharp: I currently have 62,000 miles on my '00 Ram Cummins. It's a 2500 Laramie 4X4, QC, Short Box and I like it very much. No major problem. The only thing I would like to have is a little less noise, specially on camping ground :-)...I will probably trade it next december for another Cummins HO, 2004, 3500 Dually, SLT, Long Box, 4X4, QC. The new Cummins HO (since 2003) is now 305HP and a lot less noisy...

HDenDiesel

__________________
W126 1985 300SD TurboDiesel
W164 2009 ML320 BlueTEC (Sold)
W123 1983 240D Stick (Sold)
W210 1998 E300D TurboDiesel (sold)
W124 1993 300D 2.5 Turbo (sold)
2012 GMC 2500 Duramax PickUp
2015 Ram 1500 EcoDiesel PickUp