Life expectancy of Cummins M11
Daniel Mahoney
any of you have experience with the M11? The FLD's I've driven before
have all had Detroits.
Assuming that it's been properly cared for, how many miles can I
reasonably expect that M11 to be good for before I have to replace it?
Dan M
d...@wolf.com
Pat Durkin
"Daniel Mahoney" <d...@wolf.com> wrote in message
news:6c3567b4.03022...@posting.google.com...
The M11 and its successor, the ISM, were derived from the old Cummins L10.
The L10 had a 10 liter displacement with a mechanical fuel pump. It had
optional HP ratings ranging from 245 to 270. It was pretty small for a true
Class 8 application but it wasn't really designed to be much more than a
"Baby 8" engine anyway. In its early life the L10 had a lot of problems
including faulty block castings. It went through several redesigns and
eventually became a reasonably reliable engine for its type, but honestly
most L10's wouldn't go much over 350,000 miles without a complete in-frame
overhaul.
Fast forward a few years. Cummins redesigns the L10 and increases its
displacement to 11 liters. The M11 is born. Originally available with
either a mechanical governor or computerized fuel system, it eventually
became strictly an electronic engine due to stiffer emission regulations.
By this point the lowly L10 had morphed into a fairly respectable
lightweight engine with several optional power ratings - the most common of
which was 370. Lifespan potential had increased to over 500,000.
Are you familiar with the so-called "B-50" rating system?
It's an engineering term that basically states 50% of the engines in a
particular family of engines will go X miles before overhaul. It's a
statistical tool. It doesn't guarantee that all the engines will go X
miles. It only says half will go X miles. It's a pretty reliable system
and it's important for the engine manufacturer because it helps determine
how much warranty the engine maker can safely place on the engine to assure
potential buyers.
The latest B-50 rating I read about the ISM - which is the latest version of
the M11 - was 800,000.
That's a pretty respectable number. It's come a long way since the earliest
L10 ancestor.
This is all theory as far as you're concerned. It's impossible for anybody
to tell you with any certainty how much life is left in your used M11. But
the engine certainly isn't a "throwaway" anymore. There may be quite a bit
of usefuel life left in it. Or not.
One good thing about the truck you describe is that it probably won't cost
much to buy. It's a Freightliner. It's an FLD. And it has an M11 instead
of the premium big-brother N14 or Cat engine. All of which probably means
you can pick the thing up pretty cheap. If you buy it right maybe you can
afford to do an in-frame on the thing before you ever put it in service. Or
at least drop the pan and inspect/replace the mains and rods so you know
what to expect out of the thing.
Good luck.
Pat
Jerry
We have a M11 in a Freightliner that we got at 650,000. It was never rebuilt
and it hauled 80,000 lbs of flower and had to pump it off.
We had a inline done at just over 900,000. Before the inline it never used
oil. It now has 1.3 million miles on it.
Jerry
Pat Durkin
"Jerry" <j...@itis.com> wrote in message
news:_mx5a.5504$6a2.2...@kent.svc.tds.net...
>
> We have a M11 in a Freightliner that we got at 650,000. It was never
rebuilt
> and it hauled 80,000 lbs of flower and had to pump it off.
> We had a inline done at just over 900,000. Before the inline it never used
> oil. It now has 1.3 million miles on it.
Good comments Jerry. There's nothing at all wrong with a late model M11.
The 900,000 miles you got is not greatly at odds with the 800,000 mile B-50
rating. Some won't make it that far and others will go farther. They'll
average 800,000 before in-frame.
The important thing about the M11/ISM is that it is basically a pretty sound
engine. It'll "hold" an in-frame overhaul and go about as far in its second
life as it did in its first life. The old 2-cycle Detroit 71's and 92's
often needed to be redone every 125,000 miles after the first rebuild.
Apparently their blocks would warp or something and if they weren't
line-bored at overhaul they wouldn't make it 25,000 miles before shooting
craps all over again. Cylinder heads would warp too, if the engine was ever
overheated a little. They had constant head gasket leaks because all the
metal was changing shape all the time. The M11 has none of those problems.
Don't worry about the engine life. You'll outgrow the truck before you kill
the engine.
Pat
Daniel Mahoney
I now have a reasonable basis to use in evaluating how much the rig is
worth to me.
Dan M
d...@wolf.com
dave
good experiances with the m11 hauling bulk cement.
reliable but not up to the job i was sent to do, over donner pass
everyday,just not enough power.
but lasted and never left me stranded.
i believe it was inframed @750,000 mi.
mudflapnews:6c3567b4.0302...@posting.google.com...
>Zeke<
> I'm considering picking up a Freightliner FLD with a Cummins M11. Do
> any of you have experience with the M11?
I drove a Freight Shaker with a M-11 for a couple of years in the
Northwestern US. The engine was a bit under-powered when I was grossed out
@80K, but with lighter loads (<70K) it worked quite well. Never had any
trouble with it.
Daniel Mahoney
>
> It's an engineering term that basically states 50% of the engines in a
> particular family of engines will go X miles before overhaul. It's a
> statistical tool. It doesn't guarantee that all the engines will go X
> miles. It only says half will go X miles. It's a pretty reliable system
> and it's important for the engine manufacturer because it helps determine
> how much warranty the engine maker can safely place on the engine to assure
> potential buyers.
Is there a decent online source where I can find the B-50 numbers on
other engine models?
Dan M
d...@wolf.com
Pat Durkin
There's no single source that I know of where an interested party could see
all the various B-50's together - although maybe one exists. If you don't
mind doing a little digging the engine maker's own websites have at times
shown B-50 ratings (but not all the time - website contents change now and
then).
I can tell you this: You won't find a great disparity between any of the
engines built during the past 5 years. There really isn't a bad engine
being made today. Just about every Class 8 engine will have a 700,000 mile
or better B-50 rating. I will add though that my personal experience with
Detroit Diesel 60 Series engines was better for engines built before the
1998 emission standards took effect. The 60 Series built a good reputation
during the late 1980's and most of the 90's but I've heard several reports
about early failures on 1998 and later Detroits. I don't know how
widespread this is but I suspect it may be fairly prevalent - especially
with 500 HP versions.
Pat
Jim Peters
a quick Google search but found nothing about B-50 or B50 that related to
engines or trucks. Could you provide more information about B-50? I'd be
most interested t learn more. Thank you.
Big Iron
"Jim Peters" <no...@email.com> wrote in message
news:rWb7a.72300$zF6.5...@bgtnsc04-news.ops.worldnet.att.net...
Three or four years ago I found the information you seek on the
International truck site under a school bus category where they were
defending the T-444E against the B series Cummins. I know that the site has
been completely reworked since then, but it might be worth poking around
over there. I never found anything about it at Cummins.com, but who knows,
maybe they've got something over there now?
Robert
Pat Durkin
"Jim Peters" <no...@email.com> wrote in message
news:rWb7a.72300$zF6.5...@bgtnsc04-news.ops.worldnet.att.net...
Well, here is a link to a Cat engine distributor with some spec breakdowns
on C10, C12 and C15 models showing B50 ratings of 900,000 - 900,000 and
1,000,000 miles http://www.atlcat.ca/truck.htm.
I've also seen reference to B50 ratings in published Cummins and Volvo
literature but I haven't searched for it on the web lately. The Cummins ISM
was rated at 800,000. The Cummins N14 (now discontinued) was rated at
1,000,000. I have not seen a rating on the relatively new ISX Cummins but
have been told it is also 1,000,000 miles, as is Volvo's VE D12. If you
contact distributors for these products I'm sure they can verify these
ratings.
Pat
Big Iron
"Big Iron" <ram...@aol.common.gov> wrote in message
news:I0g7a.279259$vm2.212653@rwcrnsc54...
Well, I'll be darned, it's still over there:
http://www.internationaldelivers.com/assets/pdf/dyk236.pdf
Robert
Pat Durkin
> International truck site under a school bus category where they were
> defending the T-444E against the B series Cummins.
Yeah. I think I saw that article too. In fact if my memory serves IHC
stated Cummins had unfairly compared quoted IHC's rating. They said Cummins
had cited Harvester's published "200,000 Mile" life-to-overhaul for their
T444 engine and compared it against Cummins' "350,000" mile life-to-overhaul
(for its little ISB engine). The only thing missing, claimed Harvester, was
an explanation by Cummins that they were comparing their own "B50" rating
against Harvester's "B10" rating.
WHAT? Now if you're thinking "B10? What's a B10? I thought we were
talking about B50 ratings!" That means YES...there IS a B10 rating on every
engine too. A gold star for everybody who can figure out what a B10 rating
is.
So if there's a B10 rating and a B50 rating, then is there also a B20, B30,
and a B40 rating? Yup.
The key rating is the B50 because it represents half of the engines produced
in a certain family of engines. But this Bx system of failure analysis can
map a curve of all the engine family's statistical lifespans. It sounds
like black magic but it's really an exact measuring system. It doesn't
guarantee any single engine will go X miles but it DOES say that if you buy
a hundred of them and keep them all 'til their first o'haul you'll find all
of them met expectations.
Pat
walkerstranspor...@gmail.com
Are you completely sure about that?
What do they look like?
Fire rings ....yes.
Headgaskets??? Never seen one before.