Downsized engines=shorter life?

[Retiredguy2]

Seems like the engines in new vehicles constantly get smaller to increase mpg and I wonder how downsizing will affect service life. I began pulling travel and boat trailers back in the early 80's and the understanding then was that a small engine straining to pull a load would consume about the same amount of fuel as a larger engine that could comfortably handle the same load, and the bigger engine would have a longer service life. My last Ford F-150 pickup had the 5.0 V8 and I used it to pull a 7000 pound travel trailer...it did the job okay but had to work hard at times. Today's F-150 is available with an engine as small as the 2.7 Ecoboost and they are rated to tow more than the 7000 pounds my truck used an engine almost 2X the size to pull.

I would have reservations about using such a small engine for 7000 pound towing because I would wonder about the service life. Thank you for any input on the subject.

 

[MMagis]

I think one thing you're not considering is the amount of HP produced in a smaller package these days. Have you compared the HP of your old truck to that of the newer 2.7? Also keep in mind that a vehicles rated tow capacity is a fine example of creative accounting. If there's one thing that can be said about engines of today, it's that they last a lot longer than those from 30 years ago.

 

[Retiredguy2]

I think one thing you're not considering is the amount of HP produced in a smaller package these days. Have you compared the HP of your old truck to that of the newer 2.7? Also keep in mind that a vehicles rated tow capacity is a fine example of creative accounting. If there's one thing that can be said about engines of today, it's that they last a lot longer than those from 30 years ago.

Sorry but I think you missed my point...I know today's engines produce much more horsepower. Look at a drag racing engine, for example...it produces huge amounts of horsepower but the service life may be only one or two trips down the strip. AND...does anybody really know for certain today's downsized engines WILL last longer?

 

[HHR]

I've pulled a 12,000 pound trailer load of hay with a 1991 F350 with the 460 V8 and one fuel injector wire chewed off by a rodent. The truck still pulled the load fine and other than a slightly rough idle, it was hard to notice the "dead" cylinder. If you dropped a cylinder on a 2.7L EcoBoost under load, the thing would probably go into limp mode and cut all the boost. Do you think a 2.7L V6 short one cylinder and without any advantage of forced induction would pull a loaded trailer very well?
The margin for error on these smaller engines simply isn't there.

 

[MMagis]

How did I miss your point? Maybe you missed mine? The only reference to engine size you gave was the liters, not the HP. HP is all that matters in this discussion.
I don’t know how you can even question whether engines of today last long than they used to. It’s common knowledge that they do, and not by a small margin.

Edit: Maybe I’m starting to get what you’re asking. Personally, I think you’re grasping at straws trying to make the argument. I don’t know the answer, maybe no one does. But there’s nothing to even suggest the “smaller” engines won’t last as lone, quite the contrary.

 

[KennyG]

I wouldn't be concerned about it. The smaller engines can get higher output in two ways - higher engine speeds and higher internal pressure. Horsepower is a function of torque and RPM and torque is directly related to the "brake mean effective pressure" inside the cylinders. New engines like the ecoboost are torque engines, not rpm engines (although they will rev when needed). The engine internals have been beefed up to take the increased pressure. The reliability problems with earlier turbo and supercharged engines was that they were essentially normal engines with boost added. When you design for boost to begin with, no problem. Diesels solved this problem years ago by beefing up the internals which is why they cost more and last longer.

 

[r8nger]

Today's engines are also producing power more efficiently. They also are burning cleaner, less contamination. Lubricants are also better, contributing to longevity.

 

[DarkBlack]

I've pulled a 12,000 pound trailer load of hay with a 1991 F350 with the 460 V8 and one fuel injector wire chewed off by a rodent. The truck still pulled the load fine and other than a slightly rough idle, it was hard to notice the "dead" cylinder. If you dropped a cylinder on a 2.7L EcoBoost under load, the thing would probably go into limp mode and cut all the boost. Do you think a 2.7L V6 short one cylinder and without any advantage of forced induction would pull a loaded trailer very well?
The margin for error on these smaller engines simply isn't there.

True.
The opposite view of it though, is that an 8 cylinder engine is more likely to drop a cylinder than an engine with 4, or 6..

 

[DarkBlack]

I've pulled a 12,000 pound trailer load of hay with a 1991 F350 with the 460 V8 and one fuel injector wire chewed off by a rodent. The truck still pulled the load fine and other than a slightly rough idle, it was hard to notice the "dead" cylinder. If you dropped a cylinder on a 2.7L EcoBoost under load, the thing would probably go into limp mode and cut all the boost. Do you think a 2.7L V6 short one cylinder and without any advantage of forced induction would pull a loaded trailer very well?
The margin for error on these smaller engines simply isn't there.

True.
The opposite view of it though, is that an 8 cylinder engine is more likely to drop a cylinder than an engine with 4, or 6..

 

[bigdeano]

How long they're going to last would depend on how beefy the bottom end is, like diameter and width of bearings. More boost equals higher bearing loads.

 

[Retiredguy2]

How long they're going to last would depend on how beefy the bottom end is, like diameter and width of bearings. More boost equals higher bearing loads.

And you just hit THAT ONE right on the head....today's automakers are constantly trying to build lighter and cheaper vehicles...my wife formerly had a 2011 Malibu with the regular 2.4 Ecotec...it was so slow it could barely get out of it's own way...NOBODY can convince me the 2016 version with the 1.5 turbo Ecotec is going to be built any stronger engine wise than her older model was.

 

[Professor Marvel]

And you just hit THAT ONE right on the head....today's automakers are constantly trying to build lighter and cheaper vehicles...my wife formerly had a 2011 Malibu with the regular 2.4 Ecotec...it was so slow it could barely get out of it's own way...NOBODY can convince me the 2016 version with the 1.5 turbo Ecotec is going to be built any stronger engine wise than her older model was.

I don't understand. Are you trying to say that you don't get something for nothing? You seem to think that a little teeny motor motor running hard as he!! might not last as long as larger motor just chugging along. WHY that's just crazy talk.
If it has ECO in it it must be better.

 

[Diamondpilot]

Seems like the engines in new vehicles constantly get smaller to increase mpg and I wonder how downsizing will affect service life. I began pulling travel and boat trailers back in the early 80's and the understanding then was that a small engine straining to pull a load would consume about the same amount of fuel as a larger engine that could comfortably handle the same load, and the bigger engine would have a longer service life. My last Ford F-150 pickup had the 5.0 V8 and I used it to pull a 7000 pound travel trailer...it did the job okay but had to work hard at times. Today's F-150 is available with an engine as small as the 2.7 Ecoboost and they are rated to tow more than the 7000 pounds my truck used an engine almost 2X the size to pull. I would have reservations about using such a small engine for 7000 pound towing because I would wonder about the service life. Thank you for any input on the subject.

I have the 3.5 F150 EcoBoost. I can tell you it will out pull any large displacement gas engine I have had. The biggest being a 1997 Dually GMC 454. At 70,000 miles it's been absolutely trouble free as are most new things.

Chris

 

[Retiredguy2]

I have the 3.5 F150 EcoBoost. I can tell you it will out pull any large displacement gas engine I have had. The biggest being a 1997 Dually GMC 454. At 70,000 miles it's been absolutely trouble free as are most new things.

Chris

I have a 3/4 ton GMC with the 8.1 and 4.10 gears....it has been quite trouble free and is a beast when towing although it eats up gas.

 

[KennyG]

I don't understand. Are you trying to say that you don't get something for nothing?

There is quite an upcharge to move from the 5.0 V8 to the 3.5 Ecoboost. It's not paying for unreliable technology. If the technology didn't pay off, every thing would be based on cubic inches. Ever watch a 1200 cc Harley take on a 600 cc sport bike?

 

[MossRoad]

I have the 3.5 F150 EcoBoost. I can tell you it will out pull any large displacement gas engine I have had. The biggest being a 1997 Dually GMC 454. At 70,000 miles it's been absolutely trouble free as are most new things.

Chris

You're saying a 213.583 cubic inch engine outpulls any 454 you ever had?

1997 454 = 410 ft pounds of torque and 290HP

Gotta be wrong.... so I looked it up... Well heck, the 3.5 gets well over 300hp and 420 on torque. Who'da thunk it? :confused2:

Its the electronics on these new engines that really bothers me. Time. Not mileage. Electronics don't last as long as the mechanicals. Only time will tell.

 

[KennyG]

Another indication of how tough the ecoboost is built - as I understand it, the weight of the 3.5 EB and the 5.0 are almost identical. Some of the weight is the turbo but some is probably a really strong block and crank.

 

[ultrarunner]

I've been wondering the same thing... reliability/longevity over the long haul like the 25 years or so I keep my vehicles.

Have to be some tradeoffs using thinner and lighter materials for drivetrain components.

I've seen cast iron engines overheat and go on for years... also seen aluminum engines overheat once and that was it.

Guess time will tell...

 

[dodge man]

Just my opinion here, not really based on facts but experience, but it seems like an engine failing is not usually the reason a vehicle goes to the scrap yard. I'm talking an actual mechanical failure where the engine would have to be rebuilt or replaced. Its usually the electronics, transmission, body falling apart or a number of smaller repairs piling up and not worth fixing.

I see no reason the low displacement turbocharged engines should be any different.

We have 3 of the 2014 5.0 trucks at work. 4x4 extended cab short bed. I'm impressed with the trucks, good power, very comfortable, but the gas mileage sucks. They are work trucks so the one I drive carries a lot of weight, they get driven in town a lot, idle some, driven around farm fields at low speed, but its not uncommon to see the fuel mileage at less than 10 mpg. Even out on the highway I never see them get up near 20 mpg. I've never driven the Eco-boost but I'm betting they would get better MPG.

 

[ultrarunner]

The number one reason for most otherwise sound vehicles heading for scrap is emission test failure.

In California just about everything 1976 and newer is tested.

Rust is NEVER an issue.