If the diesels last forever, then why .... - PeachParts Mercedes-Benz Forum

jbach36 · #1 05-27-2007, 12:57 AM

I was looking on auto trader at some MB diesels. There's an '87 SDL, with 389,000 miles, with rebuilt transmission and engine. I saw another one on CL, saying "these cars can go 1 million miles", and I know they have a million mile badge. If these cars can go 1 million miles, why are so many rebuilt around 275k? I'm sure some last longer, and some less, but on average, there is no average of even 500,000. They're often used as parts at 350k. Maybe not yours, but many are, I see them all the time on CL, dead at 240k in some cases.

I love my 300d turbo W124, and hope it will go the distance.

jeff

lietuviai · #2 05-27-2007, 01:06 AM

I'm not sure if any make the 1M mile mark without some sort of rebuild. So even with a rebuild they're still going. The 617's can be re-sleeved so technically you can go 1M miles on the same block.

350SL4spd · #3 05-27-2007, 01:09 AM

It's all about the oil change: hot & often.

...

I really didn't mean for that to sound that dirty, I swear...

#4 05-27-2007, 01:26 AM

The highest mile MB diesel I've seen without a rebuild is 730,000miles.

Semi trucks regularly pass 1M miles on the same engine.

350SL4spd · #5 05-27-2007, 01:31 AM

And the tranny doesn't run on diesel, so don't blame it if it pitches a fit first...

MB's auto-boxes have never been there strongest suit.

Knightrider966 · #6 05-27-2007, 01:35 AM

Like anything, these cars need care and good fuel. You can make your engine last longer just by adding an upper cylinder lubricant like Lucas. I added 150 RPM just by adding it. Change your oil often and use Lucas oil stabiliser at every oil change.

pawoSD · #7 05-27-2007, 01:44 AM

Quote:

Originally Posted by 350SL4spd

And the tranny doesn't run on diesel, so don't blame it if it pitches a fit first...

MB's auto-boxes have never been there strongest suit.

??? How many auto trannies from other makers do you know of that easily surpass 200k miles with no real issues? My tranny is 25.2 years old and has almost 260k on it, and it still shifts/operates perfectly. Keep the fluid and filter changed on a regular basis, and they'll last just short of forever. Same for the engine. Our '83 has over 284k on it with no rebuild and it has ZERO blowby, and starts instantly, even in arctic temps. Mine also starts pretty good in low temps still.

The percent of vehicles that make it past 200k without huge overhauls is very low. Heck I bet the percent of cars with over 200k on them period is extremely small vs. the general car population. I'm willing to bet under 3% and I bet over half of those are MB's

pawoSD · #8 05-27-2007, 01:46 AM

Quote:

Originally Posted by Knightrider966

Like anything, these cars need care and good fuel. You can make your engine last longer just by adding an upper cylinder lubricant like Lucas. I added 150 RPM just by adding it. Change your oil often and use Lucas oil stabiliser at every oil change.

??? Not necessary, most of that stuff is snake oil. I think I saw somewhere that the lucas products allow the oil to foam up, starving bearings of their oil and shortening engine life. Just use good quality oil, synthetic is best, and change it regularly, and the engine will last a loooong time.

What do you mean "added 150 RPM" you can't add rpm's with an additive, generally you just press the throttle more to do that.

MBeige · #9 05-27-2007, 01:56 AM

Nothing really lasts forever...

captainmonk · #10 05-27-2007, 05:27 AM

my inability to stop getting divorced rivals micky rooneys that seems to be forever

captainmonk · #11 05-27-2007, 05:29 AM

ohhhhhh and about lucas i call it fake oil pressure but my mechanic called my volvo 70 series dead in the boat 3 years ago. So every oil change she gets a gallon of lucas 6 gallons of rotella holds 30 lbs at idle 55 lbs at 1700 rpms and everyone just shakes thier heads

Parrot of Doom · #12 05-27-2007, 05:40 AM

At 10 years old and 184,000 miles, my engine has no blowby whatsoever, still accelerates at book times, and only one cylinder has even a trace of ticking at idle speed.

The transmission is also similarly fine.

I'll go with what others say - change the oils regularly, and they run forever.

epssax · #13 05-27-2007, 07:10 AM

I'm pretty sure the old reliable "taxi cab" models could go a million with regular oil and filter changes and service. Iron block and head was pretty tough. Of course, anyone selling any kind of diesel will say "million miles' and the gullible public will buy it. The newer ones with aluminum heads and electric fans and switches will get hot several times due to switch or fan malfunction and you can just about forget longevity.

#14 05-27-2007, 08:02 AM

Going 1000K miles without a major rebuild is unlikely for any of these engines, 500K for a well maintained one is more realistic. I'm sure you can kill one in 250K if you abuse it enough. My 617 turbo is pushing 400K now and I expect that I will either have it rebuilt or toss in a reman somewhere in the 500+K range. I'm not going to run it until it becomes unreliable, when/if it has a problem with power and/or cold starting it will be rebuilt/replaced.

I replaced the auto trany with a reman unit at about 250K, but I don't know how it was maintained for the first 150K, it was already starting to act up (flaring) when I first got it. I suspect the PO did not maintain it very well. The "new" one is getting fluid/filter change every 30-40K highway miles; so far, so good after about 130K miles. I'll be curious to see how the tranny does with proper maintenance, hopefully I won't have to replace/rebuild it every 250K miles.

bullwinkle · #15 05-27-2007, 08:51 AM

It's all about maintenance-keeping your fuel system clean helps too (cuts down on oil contamination), the Mercedes will outlast most other car manufacturers diesel engines, but it can be hard to overcome a lazy PO's lack of maintenance (mainly oil changes)-there's no substitute for maintenance records, good ones mean MUCH LESS $$$ down the road later.