[srsomasundaram]

Hi Gurus,
Is there significant difference in MPG of 300SD and 350SDL?
Is 300SD 5 cylinder engine and 350SDL , 6 cylinder?

I was told by mechanic that the 6 cylinder engine will give better MPG than 5 cylinder?

Is it true?

Thanks for your input.

 

[PA300SD]

I average around 27mpg with my 1st Gen 300SD[5 cylinder]. My Dad's 300SDL[6-cylinder] averages around 31-32.

Not too sure about the 350SDL, I've heard in various circles that it's best to stay away from them.

 

[RAF]

I've had my 350SDL for over two years now... (just hit 195,000 miles) NO PROBLEMS. I get about 23-27 MPG with addequate acceleration and speed with the A/C on. I test drove the 5-cylinder 300SD and although "bulletproof", it was not as smooth as a late 300SDL or 350 SDL. After much research, I went with the 350 because I thought it was the most refined of the SD models. I just liked the 350SDL, I also read that there is a "troubled SDL" list out there that breaks down engine serial #s affected with the rod issue most people talk about. I found the list, and it turns out these "bad" engines were batched out early on in very close sequence, the ones that started the "issue". Then as engines, broke from use,abuse, or just life, the quick diagonsis was the "oh these were bad engines from MB" comment, then like a good urban legend....(like a cell phone can start a fire at the gas station)

I couldn't find the "hard" numbers that dictated a 350 malfunction. Thousands of engines were made for 350s worldwide, but the percentage with problems were theorized to be less than 5%. I think that's good, I don't know other car manufacturer's numbers, but I took the "risk" and love driving my Smooth 350.

Raf

 

[Extreez]

someone know how to solve this i have a 84 300sd and it has HORRIBLE MPG its about 12 mpg its horrible !!! its below usual

 

[srsomasundaram]

Thank you guys.
Your input is really helpful.

Now, I am considering purchase of 1985 300SDL with 364000 miles (64000 miles on rebuilt engine). The owner says, the engine and tranmission were rebuilt (@300000 miles) but he does not have any records. Had test drive last week and the vehicle seems to mechanically ok. He has resprayed exterior sometime ago. It is maroon exterior and gray leather interior. A/c is blowing cold but starts blowing cold air only after a few minutes of switching on.

The asking price is: $2500.

Pl. give your opinion.

 

[Extreez]

rebuilt engine with now papers sounds like a lie. Go ahead and before buying take a look under it.

 

[srsomasundaram]

Diesel car mileage question

rebuilt engine with now papers sounds like a lie. Go ahead and before buying take a look under it.

What should I look for to ensure that the engine was rebuilt?

 

[gdstealth]

has someone set your alda or fuel injection pump too high? If you smell diesel chances are this is your problem or you have a leak in the fuel system

 

[gdstealth]

Mine gets 20+ min the city and I'm a leadfoot

 

[jzaroh]

...Thousands of engines were made for 350s worldwide, but the percentage with problems were theorized to be less than 5%.

Actually the figure was 50%. Just peruse the diesel mailing list archives of MBCA.

Nobody knows what happens to these cars, and before it can be fixed, its already too late.
Once the piston has started to ovalize the cylinder, usually the #1 piston, the sleeves (yes, I have JUST found out they DO seem to have sleeves) need replacement, as well as the pistons. One piston being out of alignment for a while, slapping up against the sleeve may cause the piston to eventually break apart and do further damage (pitting and holes in piston). Then, it gets really bad.

Low oil pressure develops in the final stage, and there is excessive wear on the bearings, with the engine being toast. They are garbage when this happens. Its a toss of a coin as to when it will, if ever occur.

I've had the fine luxury of having to live through this, and seeing the shortblock and its internals FIRSTHAND. Its not a pretty site, as the engine was/is my own.

My 350SD just came back today with a used 3.0 liter from an '87 300D. This time, my car is on its THIRD engine.

Screw the 350's. When I first join the mercedesshop forums, I harped about how wonderfully refined and powerful they were.

I feel like I was conned by Molierre's Tartuffe. I've been Tartuffified!