Since fire season is upon us here, I keep thinking about all the new junk engines and the problems they can have. Fire truck engines should be exempt from any and all emissions crap, and have no electronic fuel systems.
DDEC 3 & 4 Series 60
Most fire trucks don't need a full size truck engine. Cummins 8.3 300-350 horsepower was the best choice 20 years ago and if they were not all clapped out still would be. Some did not like the CAPS pump and earlier ones came with a P-pump I think. I actually liked the ones that had the HPCR system right before DPF took over. ISL was also a good choice for larger fire trucks. Water tenders, best choice was a good commercial chassis like KW with a Cat, Cummins or Detroit in it. Anything non-electronic is far too old now, nobody to work on it/get parts.
N14 and l10 Two stroke Detroits can be if you dig up some guys in the graveyard Nothing international past like 2000
I would like to mention some 3406E prefixes, but I agree with 92U. Hard to beat a series 60 3&4. The Cat 3306 truck engine is a close 2nd.
Yeah the two stroke detroits, some how seem to be pretty dependable. And probably the most simple of the fuel systems. Nothing electronic is what I would call dependable, it takes very little to put one down. Yeah when all is good they are okay, but a small bit of corrosion in a connector or loose connection, frayed wire, fried transistor, a bit of H2o where it shouldn't be etc. then your sitting. Not cool for someones home to burn down because of a simple electrical problem with a fire truck.
When I was a firefighter/mechanic nobody's house burned down because of a fire truck failure. When a house fire call gets dispatched, at least 5 fire engines are coming, most of them are taxis for manpower and will get parked down the road idling and never used. . If one breaks down on the road another one will be dispatched to replace it. If one breaks down at the fire then just grab the one sitting right behind it. But that never happened that I know of. The same parts are used to drive the rear axle are also used to drive the fire pump, so if it made it to the fire, it will likely be able to pump for 10 minutes longer and knock down the fire. Most of the problems are discovered back at the barn and they spend weeks in the shop waiting for parts/service like anything. The older they get, the longer that takes.
That sounds pretty accurate. My town has less than 2000 people in it and I can see at least 4 firetrucks parked in the firehouse when I drive past.
Any structure fire around here necessitates the response of at least 2 or 3 local fire departments- its policy. But, these are small rural departments with one pumper each and accompanying each is a tanker. Most times nowadays its more of a problem finding enough volunteers to show up rather than an equipment problem
We had a policy, no fire truck left the barn with less than 1 person operating it.
Yup ^^^ I used to hang out at a local garage 35 years ago, and we did state inspections on vehicles. For some reason, we did a small boro's VFD truck inspection. They were not very local to us, maybe 30 miles east. The garage owner was a long time veteran in the local VFD. So maybe he did these gratis for VFD's This was a 1960's chevy, maybe 5 ton truck with a front pump. Every local VFD had moved up to newer equipment. I noticed a 10 lb CO2 fire extinguisher setting in a simple ring (bucket) on the drivers side running board, just behind the door latch. No belt latch, simply sitting in a deep enough well, to stay there. The garage owner explained it's function. When a call goes out, the first person to reach the station grabs the truck and radios out so everyone else proceeds to the fire in their own vehicle. The fire extinguisher on the running board ? Many fires are kitchen fires, or other small fires (if you get there fast enough before they grow) so the driver jumps out, grabs the extinguisher on the way out of the truck, and this is the first response, and many times it's all that's needed.
Also they have different programming to avoid the truck going down, no emissions, etc will derate or turn the truck off when it's at a fire, they will also bypass the governor and run the engine as fast as required to keep the flow rate up until the engine lets go.
Anything in the programming to allow the truck to start, run, drive, and work without the computer ?
I have heard complaining about emissions systems and talk of that but never seen it actually allowed or implemented anywhere. Never heard of one bypassing the governor, that sounds like a recipe for disaster when the water pressure transducer fails, send the engine to the moon for no reason. When I was in the hand throttle was more like a cruise control, just set the engine at a certain RPM and use your eyes to watch the discharge pressure gauge. They have electronic governors now but I am not sure how much they have caught on.
My brother designs fire trucks, every component has a failsafe so it can be used manually. I can't remember exactly what he said about the engines but irc they do have the shutdown override handy.
Best on/off road, most reliable, easiest to acquire parts for, easiest computerized engine to work on, well designed cooling system, excellent fuel mileage, all with manual shutdown over ride, light not heavy, very good engine retardation, Many, many have run over 1.2 million miles and have never had the cylinder head removed. * Series 60 12.7 DDEC 3,4, rated up to 500 hp and 1700 torque.
I had a customer who bought a mid 70s GMC firetruck, the local district finally decided to sell it after it caught fire for the third time while fighting a house fire. Only slightly embarrassing.
That makes sense. I hear on the news where the Albuquerque Fire Department will send 15 unit sto a house fire. I don't know where they would park 15 units, down the block for several blocks?
All that is fine and good, until there is a huge wild fire, and all the assets are on the job, and nothing available when its someones home going up. You can't gamble on 4 fire trucks showing up when 10 homes are cooking. So having one truck go down at any point in time can be catastrophic.
And should be a top priority system, "run with zero electrics". Like the good old cat dozers, they could be started and run with out a battery in sight. There are spring starters for diesel engines.
I have not seen any override systems. I don't work on fire trucks daily any more but still tangentially connected to them. I will ask when I get the opportunity. I will say this. Trucks are going to break. When you get a large fire that has dozens of them, some of them are going to break. You have to make allowances for the few that break. Fire trucks are a lot like RVs. Made with strange components and not really well designed or tested. Because they run very few hours compared to vocational trucks. And every one is custom built different. Plus they drive them like maniacs. It's a wonder they don't have more brake failures and such. And they give them very high HP engine ratings compared to commercial.
Money isn't really a concern with them though, I don't know the exact details but my brother was with the city department here for like 10 years and said they can be run that way in case of emergency. They had trucks sent up to fires up north here that are worth over a million bucks a pop that were written off after coming back. Something about pumping water out of a swamp that destroyed the pumps and wasn't worth fixing.
We don't have anything like that here. Local, state, fed all have overlapping fire departments (long story but it works) and all are very conscious about pinching a penny. Fire trucks are the same basic components as any other truck, nothing $1MM (yet) because anything that big would not get around the roads. Strange story there, nothing in a pump that can't be repaired, they come in half from the bottom. Just a water impeller and cast iron housing and a bunch of bolts. Not more difficult than changing or repairing an engine or transmission.
Interesting thought... At the facilities I worked at ... The electric fire pump motor didn't have the usual overload protected starters. They were meant to run till they couldn't. Same with military generators... They have a switch ... called "Battle short" or some such. Run till it can't.
Well, most trucks including fire trucks did not auto stop for overheat/LOP as far as I ever knew although I am sure some of these newfangled things can be programmed to do it, but it is up to the operator to notice the gauges and bells.... However with regard to emissions shutdowns, I am thinking DPF loading still ought not to be overridden because it is either going to plug completely or catch the DPF on fire thus making it worse.... I went on a place where I am still a member and discovered they may or may not have been discussing resistor values to bypass whatever exhaust sensor that was in short supply so those shutdowns must still be in effect.
I bought a few with that switch off gov planet never could get a straight answer what it was I wanted the turboed kubota off it for my skid loader so I shaped them and then bought 2 more and set up for a few relatives.
Don't worry man, all the fire trucks in the state aren't going to stop that huge wildfire. Pretty sure Paradise CA didn't burn to the ground because a pumper had to stop and regen . . .
So what you guys think is the best engine? 12.7 s60 (ddec 3-4) N14 (pt, celect, celect+) 3306
In the size range I agree with a P-pumped 8.3 If I wanted a class A motorhome I would shop for the P-pump years with Allison and no slideout for simplicity. Same combo for a medium brush truck.
All three of those are good choices. For emergency vehicles I would prefer not to have electronics. 3306 or N14 PT. You can turn the thumb screw on a PT pump solenoid, cross the starter and it will run as long as it has fuel.
The most dependable truck engine of all time was probably the one that was the best maintained. . .
The one left on the stand and never used.
Mine has been dependable, but low hour. Cat 3208. Not a choice of those knowledgeable But common in fire trucks. I presume because they were inexpensive. Not a lot of power, just enough.
There are a large number of Freightliner M2's around with the Mercedes MBE-900 engine in them. They must be a good engine because other than servicing I have never had to work on one.
Around these parts--taboo.
I still don't understand the fear of electronics. The first electronic engines started rolling out 35 years ago. Realistically how often does a Series 60, N14, 3406E really leave anyone stranded on the side of a highway due to an electronics issue?
I turned into a rack dump.
Agree, One item to keep in the cab and same for all three because it's the common issue with all three-CPS. The only odd issue with a 60 I've had was pressure/fuel pump took a sudden dump in the cold-but it had 1.2 mil on it.
I disagree. I can get parts for my B models far easier than what I have read about regarding new truck parts, and they are still supported quite well at my dealer as far as having work done.
IMO-the issue with tier 4-is updates causing a issue acquiring parts also. Parts that have been superseded 3 or 4 times-The belt tensioner for DD-15 was updated 3 times and Gates was the company that produced the final version that worked. Getting it was another story.
The 8V-71 is the most dependable engine ever. Seen one still start and run O.K. with a holed piston. Not running cleanly of course, the smoke levels were up over normal levels! But the U.S. military still runs Detroit diesels - around 300,000 of them, as I understand - and MTU are still churning out new Detroit 2 strokes and rebuilding all the military ones. There are a reported half million Detroit 2 strokes still in operation world-wide. Not bad for an engine that first hit the market in early 1938.
And what is the U.S. military budget, and how much waste? But the main reason is those are cheap, along with how many set and never get used but a few hundred hours. Same with allot of that type of spending. Stuck in a rut.
^ I'd go with the 671, has less parts, but maybe the extra pistons help when they are junk. Long idle times are not great for them so if someone shuts them off and also knows how to start them in winter they are fine. I set up my N14 to start with a engine controller and with a flick of a switch I have manual +12 to the ECU, manual shifter control, and a remote starter so it can be started and shifted with a can failure from the engine controller.
Why would you want to idle any diesel engine for a long period? It's the most engine-destructive, fuel-wasting, and polluting form of engine operation. I detest idiots who idle diesels for long periods, they have no idea of the damage they're indulging in. Cummins engines with PT fuel systems in particular, suffer the worst from inadequate combustion at idle.
Seen engines idle all day a lot, people don't care. I've seen pickup diesels idle all day then have to get the carbon chiseled out of them
That I would have to disagree with, 2 strokes need to be idled up to keep coolant circulating. Two strokes will go to slobbering with too much idle time, need the blower building some psi. Any truck with a 2 stroke-do the equipment check, start build air shut off check systems for leaks. restart no warm up, put in gear and slam it to the wood and keep it there all day long or till you can't stand it anymore.
I'll go one better I saw two different 8V-71's that ran with broken cranks! One of them was in a truck drill rig and we had to run it long enough to lower the mast then after we got it to the shop area fire it back up to raise mast so we could remove the engine. Yea, besides the crank the blocks had a broken main bearing perch.
It is quite amazing how engines still run with major damage. I've seen a IH V-392 gas V8 in an IH truck still running and driving, with the crank broken at the rear main. It sure made a lot of noise, though! - and I'm not sure for how long, it would've kept driving!
My truck I bought for my daughter still runs and the cam sprocket fell of the passenger side. It's an interference engine and a checked the first to cylinders and there's no damage. I'm pulling to put a new engine in. Ford 3v 2006. Well I'm sitting here in a non running m11 because of stupid international and I think it lost prime over the weekend. I carry a fuel pump to prime engines for this reason but it's on my rig and not this one, and the starter will only crank and shut off or there is a electric malfunction in this junk international cab which is a high likely event. If only I wasn't 60 mi+ from my fuel primer.
After a couple hours I was able to get it primed with ether. Truck has a starter heat sensor and you have a very limited cranking. I do blame international because they took off the filter off the fuel pump, that you can't get too because the engine is under the cab or behind guards, and use their own filter behind the cab. If this was a normal Cummins you could screw off the filter, fill it up, screw it on, and go.
Well, I'm the idiot. Some of the crane computer systems take a long time to run a full diagnostic every time you shut them off. We've got one that likes to lose its boom location if you shut it down, that's a hour procedure to manually get it set back in its parameters. It stays running. I don't like shutting down either with a pile of boom out in a close area, that's a great time for the starter to die, and there you are with 230' of stick out you can't get back in. When we've got something lifted that they may be welding, or trying to bolt items together, we may sit there 5 minutes, we may sit there 5 hours. But when they want a touch of cable up, they want it now, not after a 3 minute reboot and set up of the computer. I won't shut down when doing manbasket work either, get it running and keep it running, I'm not leaving the boys stranded up in a basket. I will vary the throttle, and sometimes just set up the idle to get a little better oil pressure, but there's really no way in the single engine cranes, to even get the engine running warm with just the pumps running. The engines will usually smoke out a little when you leave the jobsite and get them up to temp. The newer cranes running DEF are a huge pain from everyone I talk to, you just can't generate enough heat to make the emissions equipment work correctly.
If there was a piece of equipment that should be exempt, I think a crane would be top of the list.
Man lifts are another one that suck for emissions. I remember retrofitting some updates to a few that kept the pumps loaded up so the engine would stay warm.
I did not say I had a fear of just answering what I thought was the most dependable in fire situations. That electronic engine is going to take care of itself first. If it gets signals it does not like it is going to shut down. If you had a starter suck engaged, burned the wire off the starter, you can not push start that electronic engine. Yes it is uncommon. A friend of mine worked with fire trucks. Unrelated to electronic engines as their pump went out. Showed up at a house on fire and cranked it up. Sprayed some water and the stream stopped. They stood in the front yard with the family and watched the house burn to the ground by the time the next truck got there. I would hate to be the that situation saying I am trying to get flash codes of the dash.
Fear of electronics ! The problem with them is the myriad of problems that can happen at a time when you can't have that (Tenwheeler's post, yeah a pump). Its common sense, old diesel engines did not need any sort of electrical anything to run ( for emergency why complicate it more). Only one major system on them to keep in tip top shape. Never a problem with a special sensor, or a bundle of connectors and all the huge added complexity. It seems most of the time on modern cars it is always something electrical that is messed up causing some sort of problem, some times its a hidden broken wire or simple corrosion in a connector.
I was told that some medium size marine engines can spend a bit of time idling. Read a test paper on one that spent some time producing (from memory) 7 hp per cylinder for over some time over 24 hours maybe it was longer, it showed no ill effects. I think it was a 13,000 hp engine. Evidently for naval operations the engines can spend days at very low power levels. I'm probably the only one but I have never seen a problem with idling for long periods. When a person is running more than one piece of heavy equipment there is always one that gets some long idle time. Polluting ? Diesel engines use way more air than fuel when idling. What makes them suffer is eliminating the air / oxygen, as in EGR. That is way more worse than idling.
Trucks typically idle without load, and that is very bad, as long with the low coolant and oil flow. High idle typically solves this. Massive hydraulic machines have lots of load at low rpm so it's a little different. As with the cranes post above there definitely is times you don't shut the truck off, but I will high idle it. Winter temps as well.
I pretty sure there is a valid term called--Wet Stacking.
We see it bad on gensets. Even though they run 1800 RPM constantly. Most have very light load. Oily black goop can ooze from the tiny leaks in the exhaust manifold if left too long. So you go in with a load bank every once in a while and burn them out. This takes a couple hours. Sometimes you get flecked with hot carbon specks as this goes on. I have seen engines that always smoked blue, turn completely clean after a good load banking.
I bet it takes more than 7 HP a cylinder to turn a 13k HP engine so that might be a net hp figure
Wish we could have convinced people that was the problem with a little 3-53 Detroit they wanted to use just to power the block heaters of a 3412 Cat genset over the weekend in cold weather. No one seemed to understand that the problem wasn't in the 3-53. They even tried going with the smallest injectors they could find thinking that the originals were "over fueling" the engine. Not understanding that the governor controlled the amount of fuel based on the RPM of the engine, if RPMs dropped the governor increased the fuel injected and visa-versa. Had an almost identical problem with another Detroit, this one a 6V-53 in a crane carrier chassis of a drill rig. That drill rig only moved around the quarry from one bore hole to the next so it never really had to work at all. Low speeds in low gear most of the time. Heck a 3-53 would have been underworked moving that rig!
I worked on a 60 kw John Deere unit the other day. From the late 1990s so it is old school fuel system. That makes it worse, common rail does better with light load I think. Anyway they had installed 30 kw of electric heaters in the radiator air duct out the building. When lightly loaded, it kicks in some extra load. For some unknown reason they had disabled 2 of 3.
Out of curiosity what turns the load banks on on a system that uses them for a load. I'm assuming a computer system of some flavor?
A load bank is, in simple terms, a giant battery tester. Just wheel it over, connect it to the genset and apply however many kilowatts of load you desire. Load banked many generators. They'd often come off rent being run at 50% or less load. Bigger is better, right? I've had them shoot fire two feet out the stack, even had a couple catch fire inside the engine compartment due to raw fuel having leaked out the exhaust joints. Even had one so badly wet stacked that the engine would literally not even turn over because the muffler was completely plugged up inside.
This was from the 1990s so a bunch of relays in a cabinet, looked like a custom job. They had a current sensor on one leg going to the actual load, I assume if the real load gets over a certain point it will turn off the load bank. Also a delay for engine warmup. Otherwise it seems to be on at all times but I did not stand there and watch if it switches or not.
The load banks I was around were basically just large electric resistance heaters connected in a way that by flipping various switches you could adjust the load on the generator along with fans to keep the resistance coils/heaters from getting too hot.
Any of the 2 stroke Detroits are a fav around this forum. Those truck techs love them.
Lets see it was 1979 IIRC. I was almost to Corning Ca. and could see the black smoke whirling thick straight up from my fuel stop at the old Dudley & Petty truck stop. Fire trucks spraying it trying to put it out, {early 70's 352 Pete with a Green Stinker. Seems the 40MT stuck and motored , overheating the cables, which intern caught the nasty oily mess on fire. Apparently the inside of rails along with most else was covered in caked up engine oil. Burnt that puppy to a frazzle it did along with the front half of refer and load. * It wasn't uncommon to see a sign in the fuel islands stating-{If your driving a Detroit powered truck please park in the graveled area}.
I had a 1986 Freightliner FLC with a Cat 3406B engine with 13 speed trans. I now "upgraded" to a 2003 Freightliner Classic with the 12.7 Series 60 Detroit with 10 speed. I liked the way the old cat made power better, but considering its a smaller engine it really gives the old cat a run for its money. Both great engines. Sadly, some of the mechanical engines are a disadvantage if you have to hire someone to make repairs to it as they wont know where to plug in their computer! Hard to beat the big Cats for power but get ready to pay upfront and when you buys parts. All applications are different, thats like saying "What is the best gun to buy?"
Not surprisingly, we see a LOT of burnt modern trucks today (no particular makes) - but all the fires seem to start from shorts in those massive harnesses carrying huge amounts of wiring to and from the electronics. Plus, nearly every time some gorilla with a wrench works on them, they rarely clamp the harness back into the position it originally was, nor do they make sure ALL the original harness clamps are in place. Then you get the problem a friend had with his 5 tonne late-model Hino. The truck engine just stopped whilst driving along the freeway. Luckily, he was close to an exit ramp, so he coasted over to the ramp and parked up and called for a tow. The truck was in the Hino dealership for THREE days, before they found a major wire to the engine ECU was broken - INSIDE the huge harness that ran underneath the radiator! Friend remarked the harness had never been hit, removed, or damaged in any way - it could only have been a manufacturing fault in the wire, that saw the wire separate, via a small amount of movement over time. Truck is about 5-6 years old. The wire that broke was in the centre of a big bunch of about 30 wires.
And reason number one that this electronic crap has no place in a modern fire truck engine. Fires ? What about DPF fires?
Some of you guys need to start working on a time machine . . . Maybe you can power it with a Detroit!
Most fire trucks had green or silver screamers way into the 1990s. I didn't like them even back in the day but it was what everybody was used to. But even in the early 90s they were DDEC full electronic by then. They even had torque rise! Fire truck manufacturers and fire truck buyers do not care about all this stuff we talk about on here. They don't buy special programmed engines. They buy the cheapest engine that will give them the horsepower number that they want. DPF problems is something for later down the road. By that time the manufacturer and the buyer have handed it off to the station crews and the mechanics. Not their problem any more.
Yep-people out for a walk pass by a burned house and don't even notice it. But they see large puddles of oil in the street and think must have been a fire around there, why yes there was a fire Marge look at that house and there was a fire truck parked right here.
I have 2 1984 8.2 v8s either one would be ideal candidates for that job
I'm pretty sure fire trucks are the only way international stays in business
That has been my thought also, that and school buses and other government agencies where the buyer has no concept of the ongoing cost of maintenance when you buy something from a company that has completely lost their way. Are they still using internal corporate engines now or did they just throw in the towel and switch to Cummins? Can't remember.
Now that we are on max force this thread is forced into dire straights.
It would need to be a non turboed one that didnt leak to bad i think the 6 71 i just got would be a good candidate . I would gladly donate it .
Madison WI and Pierce came up with a battery powered fire truck, and claimed it worked great. Most calls being a half hour with less than five miles of driving, it probably did work fine. Seems to me that a fire dept should not prepare to handle day to day business in the easiest manner, but a big enough dept can probably afford to leave their big trucks parked most days? It did have a B cummins for the pump.
Of course Madison bought a battery electric fire truck . . . lol.
I know this is an apples to oranges comparison but how great would those trucks work in a Ft Mac or Lytton scenario where fire literally overruns an entire town? Total infrastructure failure and its an all out assault to protect what you can.
Exactly why a fire dept should not get complacent running a battery truck to cat in a tree calls ten times a day and say it works great.
Battery fire truck? So funny when folks find out its named correctly, that is when the fire truck is on fire, you know a nice hot Li Battery fire that is. If they are moving into electric fire trucks that should tell a thinking person that the goal is to not put out fires. I see the whole EV craze as helping skyrocket insurance rates so the average working person can't afford to own his/her own home. I think some won't let you park an EV in your garage.
My latest ride has 2 carbs. I think I'll be continuing that trend going forward.
I personally dont feel like there is one great one of all time , what we are considering great today all had teething issues when initially released for use . The stand out for over the road are 12.7 early series 60s despite the painbin the butt diamond seal leaks and injectors filling crankcases with fuel , several cummins models of the same time period despite needing a ton of specialty tools , medium duty use IH and the dt466e despite huei and some electrical problems , 3126b i put in same class as the are basically the same in operation . Vocational uses im a bit of a cat 3406 fan boy mechanical and the older pre emmision electronic models with single turbos only, despite them liking fuel . And mack in dumptrucks and garbage trucks grey motors not the volvo engines .despite cam shaft issues and other varying issues they have ,although not being real powerhouses they did and do get the job done . Now the mp7 engine (volvo d11e? I think ) it runs well and get way better fuel mileage then the e7 etech and acert engines .this should be more whats your favorite engine per application .
Idk the mp7 but the mp8 gets about half the fuel economy of the e7
The mp7s in the fleet get about 5.5ish mpg , my etech last time i was in the laptop in that much detail was around 3.75 , dont remember if that was one of the manual trucks or allison automatics . We have manual , auto shift and allison behind mp7s theyball seem to get very similar mileage .these are all in local dump truck use , quad axle dumps . The garbage trucks were lucky to get 3 on the etechs , not sure about the mp7 powered ones .
From my years-you really see what's what working a large fleet. Owning and repairing a smattering of different one offs in many cases doesn't reveal much.
Old mechanical 466 pretty good but ancient and low power now. HEUI ones have HEUI problems and 3126 in the same boat. Can't see any reason to prefer those two over the Cummins 8.3
The e7 water truck I drove got around 5, the mp8 water truck I drove got around 3
And the 8.3 is becoming passe. * The standard was set in 1982 with the B Model Cat. Even though a full mechanical It was and still is touted. Had Cat produced it in 525 hp form for trucks, in some respects it would still be king today.
Ok a little back history on me , 4 years at a mack dealer that was also a sterling dealer , 4 years at an Ih dealer rest of my time has been in construction or garbage , in my area cummins were not common place it was cats in everything unless meduim duty , ih were the most common class 6 and 7 trucks around also . The next most common engine was the series 60 . Cummins were around but we didnt see alot of them . Demo company i worked at was cat everything , garbage is usually mack everything , company I work at now is mack dumps and a few pete tractors with cats and one cummins . I think its regional just like track loaders. . Im sure around major shipping hubs there is alot more medium and heavy duty cummins.
The one thing that sold Cummins out west-was the Jake. Jacobs had the valve timing right on a Cummins, the B models always lacked in that department until Jacobs built the 349A Jake-it was expensive with allot more valving, but the timing was correct. Problem was it didn't arrive till near the end run of the B model.
The 8.3 lives on, it's a 9.something now, all the "small" engines are getting bigger like the 5.9 became a 6.7. My guess is to keep within emissions, bigger cylinders=less high pressure to generate NOx and stuff. Speaking of Jakes, the 8.3 and its successor got good Jakes once it turned into a DPF engine. Before then they had the exhaust flapper valve option, better than nothing but not very strong and had to run the engine at well over high idle RPM to get good braking effect from it, it was allowed to run it that fast in the operator manual under braking but had to watch it like a hawk to keep from going too fast. When the Jakes came out that all went away, it held back just like a real truck engine even at low RPM and hardly any noise through the giant DPF/muffler.
I don't hear any kudos for the old genuine Allentown Mack Maxidynes - particularly the 237HP ENDT-673. I ran one in an F-785 Mack in the 70's and 80's and that engine was a pearler. Had the 6 speed Maxidyne with the massive OD, and you had to lug it down to 1300RPM minimum before you could change back to 5th. Previous owner ran a home-built exhaust system that exited right in front of the RHF set of duals. On a hot night on a long grade, pulling a tandem dump trailer, grossing 38 tonnes (83,750lbs), as the revs pulled back down, that pyrometer needle would climb and climb, and you'd gradually see a tongue of flame in the rear view mirror, out the end of that long exhaust! Couldn't do that with many truck engines, without melting valves. Never had a skerrick of problems with valves or anything else on that engine.