As far as gas (non diesel) engines go, I am a little confused about which cars have the srtaight 6 and which have the V6. I am thinking maybe they changed over in the early 90's? I have always like straight 6's in general. Does anyone have any opinion on the Mercedes engines? I think I would really like a C or E class car with a straight six and a stick and sport suspension. Does such a thing exist in the used car market? I am thinking maybe a 93 E320/300E or maybe 2001? Please help!!

Thanks,

Mike

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1998 C230 330,000 miles (currently dead of second failed EIS, yours will fail too, turning you into the dealer's personal human cash machine)
1988 F150 144,000 miles (leaks all the colors of the rainbow)
Previous stars: 1981 Brava 210,000 miles, 1978 128 150,000 miles, 1977 B200 Van 175,000 miles, 1972 Vega (great, if rusty, car), 1972 Celica, 1986.5 Supra

Straight 6's were used until 1997 in all cars except the W140 S classes, which continued to use the straight 6 until the end of the model run in 1999.

Thus, with the exception of the above mentioned S class, all MB's have been using the V6 starting in 1998.

The 300E was available with a 5 speed stick, but is was only for two years early in the model run, I think '87 and '89. Very few were imported into the U.S.

Larry Bible has one.

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Paul S.

2001 E430, Bourdeaux Red, Oyster interior.
79,200 miles.

1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".

The stick shift 300E's were sold only in 1986 and 1988.

Both the straight and the V's are great engines. The straight sixes do sometimes have head gasket problems, but they are very smooth, tractable and long lived engines.

The V6's are even better engines. They are an absolute masterpiece of an engine. I have seen one torn apart so I've seen firsthand the construction and features of thise engine. A few years ago I was surfing around looking for information on the V6 engine and found a site where they had chosen the top 10 engines in the world. The Daimler Chrysler V6 was number one on their list.

Beyond having outstanding construction features and being picked by someone as their top choice, these engines have proven to be unbelievably reliable as observed by the MB techs at the dealerships that I've talked to.

Have a great day,

Wow,,, that surprises me Larry, as I am an old die hard straight six proponent. I should have known.

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95 SL500 Smoke Silver, Parchment 64K
07 E350 4matic Station Wagon White 34K
02 E320 4Matic Silver/grey 80K
05 F150 Silver 44K

Unless you consider the harmonic balancer part of the engine or exceed the FSS oil change interval with dyno oil.

Aside from the faulty harmonic balancer design, I have to agree with Larry's comments. My 98 E320 V6 has been very reliable, the only problem I had is minor oil leaks from the valve cover gasket and oil filler neck.

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Ray
1998 Mercedes E320, 200K Miles
2001 Acura 3.2TL, 178K Miles
1992 Chevy Astro, 205K Miles

The V6s seem to be noisier, not as smooth. The techs at the dealerships have not seen that many high miles cars yet. I think the jury is still out on the question of longevity.

Part of what has always attracted me to Mercedes is that they stuck with the Inline-6 design long after many other manufacturers gave it up. The sound of an Inline-6 accelerating, and the lack of vibration associated with it, sends chills down my spine.
I hope they bring them back at a time when I am affluent enough to purchase a new Mercedes.
~D.J.~

"straight six, stick, sport suspension" - sadly you're describing a BMW, not a Mercedes.

Sadly, the move from inline-6 to V-6 was a Schrempp-driven move rather than an engineering-driven move. The move to the V-6 was driven mainly by economics -- it is a direct descendent of the V-8 design and can be produced on the same line. This significantly reduces manufacturing costs over the inline-6 engines, which required a separate production line.

There are demonstrated advantages (in general) to inline-six designs over v-6 designs, in terms of smoothness. The knowledge that MB made inline-six engines for many decades I guess was given up with the demise of the M104 in the mid-late 1990s. MB inline-six designs have been proven over many years, despite some warts (such as the head-gasket issues, which were an auxiliary part design (materials) flaw as opposed to an engine design flaw).

Notice that today's V-6 designs don't offer significant (discernable) power or efficiency improvements over the M104 designs. Also note that V-6 engines with balancers tend to steal horsepower from the engine.

It is also telling that BMW still continues to manufacture inline-six designs for its cars.

My two cents.

Cheers,
Gerry

The V6 is not as smooth running as the inlines????? You MUST be kidding, or you have never driven both of them.

My M103 engined 300E is indeed smooth running, but my M112 engined C240 was so smooth it was like driving a car with an electric motor!!!!

There are other advantages to a V design other than being built with parts interchangable with the V8. The V design allows for a lower hood and shorter engine compartment, allowing for a little better aerodynamic capability.

If you think that the 104 or 103 engine designs are superior to the 112, you have not looked into the innards of all these engines. All of them are great engines, but the 112 is an engineering masterpiece with such features as; roller rockers, three valves/cylinder, cold cracked connecting rods, alloy liners, short skirt piston design, low tension piston rings, cross bolted mains..................................

These engines have been out almost 8 years now and there are enough high mileage examples being seen to know that they don't have any achilles heels like the head gasket or timing cover sealing problems of the 103/104 engines.

The harmonic balancer problem was the rubber used in the harmonic balancer and could have/would have been a problem regardless of what engine they were bolted to.

The sludge problem was caused by the factory recommending the FSS intervals with dino oil. A huge blunder on MB's part, but again, regardless of what engine you did this with, the result would have been the same.

I like the 103 and 104 engines also, but if you think that they are better engines than the 112, then you are either not aware of, or not facing the facts.

I wonder if there were people with such resistance to change when the auto industry went from flathead to OHV?

Have a great day,

Currently owning both engines (97 E320 and 01 SLK 320), I'd have to say that the M104 idles a lot smoother than the M112. During idle, the M104 even sounds better than the M112. The M112 has always "ticked" during idle that I have heard in pretty much all the M112 cars, so I know it's nothing wrong with mine. Once you get going, both engines are smooth as silk. The M112 does have a much flatter torque curve.

This is not saying any one engine is better than the other, just some facts I've noticed owning both.

I can't say for longevity for either, since both my cars are considered low mileage for a Mercedes (SLK has 24k miles on it now and the E class has 99,000). The M104 in my E class has not missed a beat and I've had no head gasket or transmission issues whatsoever.

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1997 E320

The ninety degree V6 configuration has both first and second order rocking couples. The first order couple is balanced by a counter-rotating balance shaft, but the second order couple remains. A 60 degree V6 lacks the first order couple, but still has a second order couple.

The inline six configuration is inherently balanced. There are no shaking forces or rocking couples below fourth order, so if the crankshaft is sufficiently robust to prevent torsional vibration problems, an inline six is inherently smoother than any V6 configuration.

Since both the V6 block and head are aluminum, it is less likely to have longer head gasket life than the iron block/aluminum head inline six. Also, the V6 has cast in high silicon alloy aluminum liners, which have a lower wear rate than cast iron as long as they don't score.

Duke

Larry - are you sure 'bout those alloy cylinder liners? I thought these were an aluminum/silicon alloy, with the aluminum etched away leaving a silicon surface (like the Chevy Vega 2300 motor of yesteryear).

My two m112 engines run great, but they are both still low mileage. The lack of a cylinder liner scares me the most with this engine.

thanks for your observations,
Dan

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2001 e320 wagon
2004 F350
2006 Crown Vic

My point exactly, stated more eloquently and in more detail.

Given that the current V-6 is said to run rings around the inline-6 designs in every conceivable manner, I haven't seen any response or info as to an increase in overall efficiency or power generation of the V-6.

I think the benefits of 3-valve vs. 4-valve technology can and should be debated as well.

The bottom line, is that the V-6 engines were conceived, designed and produced to meet reduced cost targets. It's a decision that is in keeping with other MB quality, design and engineering decisions over the past 10-15 years.

Why does BMW refuse to go the V-6 route and maintain its inline-6 designs?

Cheers,
Gerry

Another point to consider: gas mileage.

2002 E320 4-matic 25K mi just did 29.0 mpg for an 80 mile round trip on highway, avg. speed 69 mph, windows closed, sunroof tilted open, a/c on, very light winds, no passengers, easy driving style, Sunoco 93. Looking thru the gas mileage thread, I don't think you'll get that with an IL6.

I find it hard to imagine a smoother running engine than this V6, but since I've never driven the IL6 I'll just have to take the word of those who have.

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2002 E320 4-Matic
2008 Subaru Outback
2009 Subaru Forester