DanD.

Hi All,
Just wondering how do you drive your diesels?
Im talking when engine warm.
I have read in the past some article or posts can be in this forum
do not rev higher than 2.5RPM and don't accelerate rapidly. On my ML red zone starts at 4.2

So far I have 75K on it and no problem.

kajtek1

Old diesels were not too well balanced to run at redline and with low rpm torque, there was no need for it.
But I am firm believer in Italian tune-ups and everybody advise that AddBlue system like high rpm at least once in a while.
My diesels, with normal use of 1/2 of the "throttle" do go to 3000 rpm, but once in a while I don' t hesitate to push my foot on the floor for 3-4 gear changes.

rapidoxidation

I've had diesels for about 2 decades now. 3 trucks (Chevy 6.5 turbo, 6.6 LB7 and 6.6 LLY) and 3 cars (VW Jetta 1.8 turbo, Mercedes 300D, and this E320 CDI). I've never hesitated to flog it when I feel like it - when it is at operating temperature. Gotta keep those manifolds clear! I have yet to experience a problem related to the way I enjoy the engine.
Note that after a "spirited" run the driver is well advised to give the turbo an opportunity to cool for a minute or two prior to turning off the engine. One doesn't want the oil to turn to coal on the turbo's bearings.


137K miles on my CDI, and it is regularly at 3Krpm and sometimes (not often) hits 4K
240K miles on my LLY, and gets to 3K every now and then. Almost never over that.
The 300D had 240K on it when I gave it to my nephew who drove it 1000 miles home without a hitch
The 6.5 had over a quarter million miles on it when I sold it
The other 6.6 had about 180K on it when it got totalled in a kind of minor fender bender. Crumpled up like a cheap suit.
The VW... Great engine, POS car. Sold it with 140K on it.

In my opinion, babying the engine is a quick way to fill the intake manifold with sooty goo.

rocky raccoon

Cruise at 70mph which is speed limit in Virginia, about 3200rpm. Have had it to 95mph but not sustained. EGR valve removed and engine burns clean and smoke-free. Burns about 1qt/4000 miles. Car is a 1983 300CD (OM617 5-cylinder Diesel) with 345k miles. My daily driver.

DanD.

Thank you all, very good info. Looks like old engines are very strong vs new ones.

rocky raccoon

True Dan. The OM616/617 engines are full cast iron lumps and very durable. I also have a 2008 E320 (V6 Deisel) and although a great place to sit and is faster and more economical to run I still prefer driving my 83. I do not expect the E320 to reach 345k miles without replacement.

kajtek1

There is member on other forum driving one with over 440k miles. From what I remember - he only replaced timing chain as a precaution. I just replaced my 642 engine after it suck water. Took the old one apart and at 180k miles the engine still shows crosshatch marks on cylinder walls.
Valves/heads look perfect. They only issues are weak seals on oil cooler and carbon clogging intake/EGR.

rocky raccoon

Hope you are right Kajtek. So far it has been dead-nuts reliable since new.

kajtek1

Reliable they are, cheap they are not.
With complexity of the engine everything becomes horror repair. To get to starter you need to remove DPF and it is not easy access. With my tools and lift I think that pulling engine out for any more complicated work is the way it was design.
I learned the hard way that to disconnect all the wiring on the engine is humongous job, while thinking back, pulling the harness plug from ECU, disconnecting front hoses/radiator, 4 bolts at flex disk, 2 bolts on transmission mount, 2 bolts on MM, easy accessible fuel hoses and main power disconnect. I think doing it now I could have engine out in 2 hr, maybe 3.
So my 642 should be good for few years, but I hope somebody will come with "miracle in the bottle" what will clean swirls flaps without putting week of work on it.

DanD.

I believe every one has own definition of reliability.
If I can get 150K miles from it without DPF, AdBlue heater issues and especially oil leaks I would considering MB engine reliable.
In my opinion this days any engine should be able to make 150K mark without major repairs.
Of course proper maintenance (frequent oil and filter changes) and normal operation are must.

kajtek1

But you can't compare reliability the real dial-phone (know people who still use their 50 yo model) to modern android.
My 2014 4-banger has 7 sensors on exhaust alone. Had to change couple and they retail +- $500 even internet dealer sells them for $350.
AddBlue is new technology and still has baby teeth,
But when you pass gas stations for 800 miles, you tend to smile

DanD.

Failed electronics is fine with me, I have concerns if mechanical parts can last 150K.

mersum1es

I'll floor mine every time I can! German car engineer has designed 'kick down', so it must be used... I always use 80-100% power when accelerating.

W210 around 450.000 km
W220 215.000
W211 260.000 (when totaled by my wife)

W220 has been most expensive to maintain so far even I have owned it 6 months... lol

Etienne Lau

I used to own a 2011 VW Touareg TDI(Diesel). If I babied the engine, I would get all kinds of check engine lights related to NOX sensors. But when I drove it hard, ie floored every once in a while, all the NOX sensor Check Engine lights went away and never came back. So definitely would advise a bit of hard driving once in a while. Remember these Diesels were meant to be driven on the Autobahn!!!

isstay

many times pedal to the metal and until fuel cuts off I6 is well balanced internally - it runs better that way, it stays clean.

peter2772000

Same here. Only had her up to 110 MPH (+/- 175 Km/hr) but mat the beotch at least once every drive, even if only for 5-10 seconds. Hey, Stephen said I should. That's the excuse I'm giving the cop who pulls me over *wink*

DanD.

Cool. But its all speed.
How far to you push RPMs?
I found a few post do not go higher 2.5K.

Etienne Lau

If you do not go higher than 2.5K, then you are not "pushing it". Older diesels never did like to rev much, ie Pre 2007. But these newer models like to rev and will take revving up to 4000 just fine. If you keep the revs at 2.5K or lower, then you are literally just babying the engine. Should you take it up to red-line? NO.

DanD.

My red line starts at 4K. Engine sound at around 3.3 so hard and loud, kind of not natural for it.
Before 3K its not even noticeable inside.
But I got it boos is required to keep it clean.

peter2772000

I hit redline when I mat it, I let the tranny shift itself.

kajtek1

Somebody posted it before that when you push kick-down switch during DPF regeneration - the process gets aborted.
I am the guy who likes to know what is happening with my cars and am upset with lack of any indication when regeneration occur.
In MB sometimes I smell regeneration, but on my Ford truck, I there is nothing that tells me it is happening.
For some troubleshooting I used Torque on my android to monitor DPF parameters, but torque seem to give false data as there is no way my exhaust can work with 1,300 psi. Still observing temperatures you can see regeneration going.

peter2772000

kajtek1 has a point. What a shame that we can't tell when the vehicle is regenerating. A regen dash light going on would allow us to drive accordingly, not shut the engine down before the process was finished etc.

BTW, why would matting the accelerator cause the regen process to shut down? The whole idea is to burn off excess soot deposits. You'd think that beating the tar outta the engine during that process would simply help due to the increased exhaust temps.

kajtek1

The regeneration process is making DPF extremely hot, to the degree where I heard that park car can have asphalt melting under.
Pushing the gas pedal to the floor in such moment might create really good fireworks.

isstay

4800 RPM (I6 revs higher than V6), this is where it will upshift when in manual shift mode.

rapidoxidation

I'm in the midst of a 6K mile trip around the country. I'm getting the best MPG at about 80mph (right around 40 miles per gallon calculated, a solid 43 indicated), which I'm a bit surprised about. I'd expect the best to be around 65mph or so, but I'll take the 80.
Regarding pushing the car: the throttle is barely being touched at 80mph. The car runs at this speed for hours on end, easily making 1000 miles in a day. Thing is, if you don't open it up every now and then it seems like crap tends to build up. My daughter was driving for a few hundred miles during one leg, and she's a bit more conservative with the throttle during merges and such. When we hit the on ramp after swapping seats, I of course nailed it to the floor for a few moments... and promptly laid down a thick black and grey cloud of impenetrable smoke in front of the BMW that was coming up fast behind us (sorry about that, dude). It was particularly grey when the transmission dropped down a gear, and I lightened up on the go pedal because of it. Subsequent WFO throttles were more and more clear over the course of the day. Power was never an issue, even when rolling (unintentional) coal.

My point? Open the damn thing up every now and then. Let it breathe.