Has anyone swapped an M11 for a 3116? I have had this on my mind for a while. Open to any thoughts. Yes, I know it is a pita. I can weld, have a cnc plasma handy and can fabricate things. I know the M11 is about 10 inches taller. Plasma cutter to the rescue ! Brit
Everything is BIGGER, you will be modifying for awhile to shoe horn that in. 3" longer not including fan, 6" wider, 11" taller overall. Specs: M11 L 1290mm w 973mm h 1142mm 51" x 38" x 45" 3116 L 1172 w 804 h 854 48" x 32" x 34" 6BT is closer 45" x 25" x 37"
Cummins 8.3 would have been the direct Cummins equivalent for that engine and it is a whole lot better engine. But I am sure still a lot of things to switch over.
I never thought much of either of those engines but the Cat was thought less of by a whole lot more people around here than the Cummins. Are you wanting to change because you have the Cat engine?
I would either stick with the 3116 until explodes or go 6BT as is more reliable as I have seen that of the 8.3 and considerably less mods for the 8.3 or the M11. Will also lose considerable ground speed on the M11 by swapping from 2500rpm 3116 to 2000-2100rpm 8.3 is same as 3116.
Cummins 8.3 way better engine then 3116 or 3176 imho
In my experience the 8.3 is not good for much over 2100 RPM either so you may have the same problem with an 8.3 if the truck is geared short for the 3116.
Also I wrote above that the 8.3 is the direct replacement but was thinking of a 3126/C7 not a 3116. I will also agree somewhat now that a 5.9 Cummins would be a good replacement for a 3116 and probably a whole lot more available. As for mods I generally do not care about that, I say if the factory configuration does not provide what you need then you need to buy one that has the right factory configuration. With exceptions of course.
8.3 torque is nice...but what dont you like about original engine....they are easy to find
How about a DT 466? Super cheap and parts are easy to find.
Running the rack and the injector cups.
Agreed
I just looked at what a FMTV M1088 is, it looks like a fairly compact cabover, I should think the physically smaller 5.9 Cummins would be just about the only choice now. Also has the advantage of high RPM and if this is like any military vehicles I have seen it is at redline somewhere around 50-55 mph.
58 MPH with a 2600 rpm engine. Depending on the OP's intended use, losing a few rpm for the 8.3 Cummins would be my choice. In the 90's I converted a bunch of M123 trucks to 855 Cummins engines VS the POS 765 V-8 they were built with. they lost 900 Rpm but the trucks still worked fine in the field. And being hauled from job to job, top speed wasn't a concern.
Parts and tools too expensive. Not sleeved.
Can you get 400+ hp out of them and still be reliable?
You want 400 hp in the little cabover? To get a real 400 reliable truck HP you need a 14 liter engine.
I have seen a few 430HP M-11's and Cat C-12's. Just sayin. Strangest one I saw was a Peterbilt 379 extended hood with a huge sleeper... It had a 430HP C12, when you tilted the hood you had to search for the engine.
May be a wacky question but when the original 3126 motor is rated at 290BHP IIRC, in what circumstances would you want 400+ without risking tearing the drive train apart in short order...? Just curious.
Well, I am considering everything at this point. This is why a put the idea out there. Maybe I am being unrealistic. I have the 3.07 high speed gears in the 5 ton chassis. Thought the additional HP would be helpful. They already have 330 hp in the military 3126 and I think the C7.
Personally I wouldn't consider going up in BHP by 35%+ (290->400+) unless I could find information that would satisfy me that the rest of the power train was capable of handling the extra oomph.
Trans is an Allison 3070. Meritor RF611 axles. Total load will be around 10k pounds (an RV conversion) . I'm just looking for more power to get through the mountains wherever, in the US.
I always say, I'm on vacation, what is the hurry? And it goes down the back side of the hill, and on the flats, the same speed no matter what engine is in it. A lot cheaper to just put something common and affordable in there and leave it alone, also. 3070 is good for 300-350 HP if memory serves.
If you're not running maxed out on the GVW and staying fairly light, you can run any HP rating you want. But I know from experience that a 320-350 HP engine can run a 50k+ truck around pretty well.
Not without a lot of work. 250-275 hp is doable all day though.
HP is fine if utilize it, your quoted weight that may never occur unless add a heavy trailer behind with a heavier load on it as the electronics will only deliver as needed(Backfeed) not as demand(foot pressure).
RV engines get much higher HP ratings than comparable truck engines since they know you are not going to use it continuously and melt the engine down. But a lot of the hard parts are different, pistons, cam, fuel injection components and turbocharger might all have to be changed along with ancillary stuff.
Used to really enjoy the braggard Truck Herders, "Put a 400 pump on my 300, Runs like it should now" They had ZERO clue and had no concept how the mechanisms worked. I doubt the person that sold them that even knew any better. Was always a tattle when a New Herder got into one of the old external Aneroid trucks, headlamp trim ring screw would be missing, so they get into a newer set up they would cry the blues trying to get someone to tell them how to add more fuel. The rub marked bent back throttle shaft cover plate was enough to tell THAT tale where they invariably got that incorrect as to adjusting for More fuel.
Got a 3406B in the shop right now that had a "Custom uprate" done on it. Has a 12" crack that wraps around the rear of the block just above the rear main saddle. Gee... I wonder what caused that?
Did not call those Custom Uprates but Custom Modifications!!
Might look at your axle ratio before swapping engines for so much power on what you are trying to do, more hp equals more fuel burning unless you are maxing out the hp in your current rig which I highly doubt at only 10k lbs. Besides the major mountain range grades like Cascadia or Rocky mountains I'm cruising most steep grades at 55 mph without the rear axle split with DT466 mechanical engine rated for 210 hp. Also have yet to screw around with turning fuel up, bolting on bigger turbo or adding intercooler. Anywho besides DT466 I run a 4:89 ratio rear with splitter (I just got fixed and haven't used yet) and this is a RV conversion itself weighing in at 15k lbs empty towing behind a 3500 lb Subaru, 4000 lb camper on the back, couple thousand pounds worth of tools and 300 gallons of diesel.
425 hp max I believe
I'm seeing up to 370 HP (diesel) on the Allison website.
3000 Series - allisontransmission.com https://www.allisontransmission.com/en-gb/transmissions/models/3000-series The 3000 Series includes close or wide ratio gearing and a maximum rating of 336 kW (450 hp). The addition of 5th Generation advanced electronic controls enhance operation and prognostics capabilities. An optional integral output retarder for better vehicle braking and reduced brake wear is also offered.
Nope. You are reading an incorrect quote from a rebuilder. 3000 Series - allisontransmission.com https://www.allisontransmission.com/en-gb/transmissions/models/3000-series The 3000 Series includes close or wide ratio gearing and a maximum rating of 336 kW (450 hp). The addition of 5th Generation advanced electronic controls enhance operation and prognostics capabilities. An optional integral output retarder for better vehicle braking and reduced brake wear is also offered.
Wonderful... What's your point? Without massive rebuilding I doubt you will jam 450 HP in that truck. Try to think realistically. A 300 HP 3306 will push a 56,000 Lb. mixer truck down the road and up the hills just fine. If your going to max out at 30,000 (maybe). A 6V-92 Detroit at 335 HP would turn that thing into a race car.
They have that very truck at the farm. I havent been around alot of long hoods and thought wow when i opened the hood. It had a propane kit and hardwood floors. Some one replaced the dash lights with blue christamas tree lights i replaced the old lights with blue ones.
Does anyone else think that the proposed conversion would be a suitable entry into a d1ck-swinging contest..?
This is in a 1086, trying to shoehorn much else in this hole would be a mess that I doubt could be managed. Three dimensionally limited and basically a bad choice for quoted HP. To be honest, I do not see the draw to Low Cab Forwards, had to work on too many over the years similar by IHC, Ford and GM that were a mess for packed together mechanisms in a confined space.
Yikes! that is tight. I see the fan is on the crank too.
What happened to the days when drive trains were rated by torque?
If you could shoe horn it in there it would be bad, I mean good. The Queens English? That bloody bitch would run! Most military vehicles are or were designed to maintain about 50 MPH. It does not matter how much HP you have if it is gear bound. That 6V can twist up and stay there all day long just turn the screws. The 6V struggled grossing 80,000 LBS but got it done. The 3116 struggled grossing 50,000 LBS. One here still getting that done. What would it cost to change gear ratios?
A lot based on the type differentials in these. Are Military specific where finding a alternate R&P ratio may be damned near to impossible.
Engine fan gets pulled in favor of large electric fan. More room. CFM is around 6600. Probably rebuild an DT 530. I believe these are sleeved. Seem like a easier engine to work on too. Parts are less expensive.