Newer Models Ford F250 Gas Vs. F250 Diesel

[DKB_SATX]

Originally Posted by Ray Eklund

Purchased our 2016 F350 double cab 6 foot bed 4x4 diesel after driving Toyota Tundras from 1981 to 2016 in the 4.7L to 5.7L engines.

~~ stuff deleted ~~

I'm not sure what you were driving before '99, but it wasn't a Tundra. The Tundra was introduced as the successor to the T100 as a 2000 model in '99 I believe. I don't think the T100 from the '90s ever had the little V8, but I wasn't following those very closely because I wasn't in the market for a truck until we bought the Argosy in 2011.

I tried hard to find a decent deal on a first-gen Tundra when I bought the Argosy, but I wanted the later ones with the 5-speed auto and the prices just didn't make sense. I bought a used F150 Lariat with WAY less miles than competitive Tundras had in the same price range, and it wasn't expensive for me to own for 6 years so I think it was a decent choice.

[uncle_bob]

Hi

Pulling a 30' around the ups and downs on the east coast has not been an issue with our 2017 F-250 gasser. It'll go faster up a 10% grade than I have any desire to go. It does downshift and rev up doing it. That's what happens when your max torque is up around 4,000 RPM. This is with a 6 speed. Next year they will have a 10 speed .... crazy ....

This *is* all at low altitude compared to the west. If I lived and regularly towed out there, I might look at things differently.

Bob

[CRH]

Super Duty trucks are getting a 10 speed?

[giantfuton]

They sure are but not until model year 2020. The job one 10R140 is set for August 2019 or thereabouts so that might mean it finds its way into MY 2020 trucks. The more interesting question is if it will be both gas and diesel or just one of them?

[Ray Eklund]

Originally Posted by DKB_SATX

I'm not sure what you were driving before '99, but it wasn't a Tundra. The Tundra was introduced as the successor to the T100 as a 2000 model in '99 I believe. I don't think the T100 from the '90s ever had the little V8, but I wasn't following those very closely because I wasn't in the market for a truck until we bought the Argosy in 2011.

I tried hard to find a decent deal on a first-gen Tundra when I bought the Argosy, but I wanted the later ones with the 5-speed auto and the prices just didn't make sense. I bought a used F150 Lariat with WAY less miles than competitive Tundras had in the same price range, and it wasn't expensive for me to own for 6 years so I think it was a decent choice.

******
You are right. Not sure what the 1981 Toyota was called. It was smaller than the T100. Mine was a rust bucket by 1985. I doubt if it could have pulled anything larger than an ATV.

My 2006 must have been our first Tundra, the last of the 4.7L. engines. Pulled our 23 foot Safari with the 2006, which did very well. Some Land Cruisers in between that were tent campers at the time. Better towing with the 2008 and 2014 Tundra. Went to the F350 to get a better view of the highway, intimidate automobiles and better fuel mileage.

The transmissions with more speeds may begin to have transmission issues towing a trailer with the upper gears. The 1981's fifth gear could be used on flat roads... so it was more of a four speed. The fifth speed went bad, replaced it with a four speed. Sold the 1981 rust bucket an hour after advertising it in the newspaper to a body shop guy. Only weak spot was the 5 speed transmission... or what we use to call... over drive.

[maroth]

I've towed my 1989 Excella with both a 2000 F250 (7.3) and now a 2011 F350 (6.7). The 7.3 met all my expectations, and I got around 14/15 mpg towing anything (stock trailer, boat, AS). I retired the F250 with 430,000 miles and it was still going strong. I waited and purchased a used (80k mile) 2011 F350 diesel. After the 100k warranty expired I had some performance mods done to it, and am extremely happy with it's performance (it was a real pain before the mods however). I now get ~20mpg regular driving and 15/16 towing. And don't have to mess with DEF any more. For what it's worth, I will pay the extra cost for the diesel every time just to have the endurance, torque and performance. The Log Bed also come with a 40gal fuel tank. Hope this helps.

[tjdonahoe]

Originally Posted by GCinSC2

And that's how Ford built and delivered the truck, their choice.

OK, how many hours does it flat rate at to R&R a complete cab? AC, coolant, scads of connections etc. And then the tech missed something, pull cab and do it over?

A sample video

Sorry Ford, that requirement just flat rubs me the wrong way. Make it a tilt forward cab and guys will line up to buy it and show off the tilt hood.

And someone mentioned that my cab will not come off because it's a 6 cyl. No its a Cummins 6 cyl, that's why it'll never need to come off.

Enjoy your choices.

I have owned quite a few fords....but on a clear summer nite you can hear them rust.. and I went to the dodge....

[Countryboy59]

Originally Posted by tjdonahoe

I have owned quite a few fords....but on a clear summer nite you can hear them rust.. and I went to the dodge....

Haha you don’t think the Dodges rust too? That’s funny. I also have quite a few pics of the cabs coming off. The Cummins is great but they break too. These aren’t semi trucks. They’re pickups.

[Countryboy59]

Originally Posted by GCinSC2

And that's how Ford built and delivered the truck, their choice.

OK, how many hours does it flat rate at to R&R a complete cab? AC, coolant, scads of connections etc. And then the tech missed something, pull cab and do it over?

A sample video

Sorry Ford, that requirement just flat rubs me the wrong way. Make it a tilt forward cab and guys will line up to buy it and show off the tilt hood.

And someone mentioned that my cab will not come off because it's a 6 cyl. No its a Cummins 6 cyl, that's why it'll never need to come off.

Enjoy your choices.

That’s funny. They pull cabs on those very often. You guy’s with 50,000 miles in 10 years wouldn’t know. Ask someone who actually works on trucks instead of just reading stuff on the web.

[pteck]

Originally Posted by AnnArborBob

<snip>
The biggest "plus" to the diesel is the engine brake. This is not just "gearing down" which is possible with a gas engine, but involves mechanically closing off some aspects of the engine's exhaust system which adds more drag to the drive train than can simply shifting down. This feature is simply not available on any gasoline engine, only on diesels (and not all diesels have this so you have to check.) I can go down an 8% grade forever with the engine brake and not have to touch the brake pedal at all. On a long decent this is a real plus.
<snip>

This is wrong, and continues to incorrectly persist a perceived advantage of diesel.

The addition of a diesel engine brake only brings to parity what a gas motor already has. Without getting into the inner workings, a gas motor inherently has engine braking by way of the throttle plate to block the free flow of air through the motor. A diesel does not have any such thing, and has to be fitted with one in order to provide adequate engine braking capability. It’s done a bit differently, but a diesel without the addition of an engine brake will not adequately slow a heavy rig downhill. This would be all the typical passenger car based diesels you would find in the smaller SUVs. Which is not a great thing. As every gas motor, even the one in smaller cars/suvs/and trucks will have reasonable engine braking capability.

[mplunkett]

Originally Posted by pteck

This is wrong, and continues to incorrectly persist a perceived advantage of diesel.

The addition of a diesel engine brake only brings to parity what a gas motor already has. Without getting into the inner workings, a gas motor inherently has engine braking by way of the throttle plate to block the free flow of air through the motor. A diesel does not have any such thing, and has to be fitted with one in order to provide adequate engine braking capability. It’s done a bit differently, but a diesel without the addition of an engine brake will not adequately slow a heavy rig downhill. This would be all the typical passenger car based diesels you would find in the smaller SUVs. Which is not a great thing. As every gas motor, even the one in smaller cars/suvs/and trucks will have reasonable engine braking capability.

Amen

[Countryboy59]

Originally Posted by pteck

This is wrong, and continues to incorrectly persist a perceived advantage of diesel.

The addition of a diesel engine brake only brings to parity what a gas motor already has. Without getting into the inner workings, a gas motor inherently has engine braking by way of the throttle plate to block the free flow of air through the motor. A diesel does not have any such thing, and has to be fitted with one in order to provide adequate engine braking capability. It’s done a bit differently, but a diesel without the addition of an engine brake will not adequately slow a heavy rig downhill. This would be all the typical passenger car based diesels you would find in the smaller SUVs. Which is not a great thing. As every gas motor, even the one in smaller cars/suvs/and trucks will have reasonable engine braking capability.

Thanks for pointing this out. I can’t believe the misinformation that’s out there. On the other hand, how many on here have actually done an engine tear down? The Jacobs brake is quite complicated.

[mojo]

Originally Posted by pteck

This is wrong, and continues to incorrectly persist a perceived advantage of diesel.

The addition of a diesel engine brake only brings to parity what a gas motor already has. Without getting into the inner workings, a gas motor inherently has engine braking by way of the throttle plate to block the free flow of air through the motor. A diesel does not have any such thing, and has to be fitted with one in order to provide adequate engine braking capability. It’s done a bit differently, but a diesel without the addition of an engine brake will not adequately slow a heavy rig downhill. This would be all the typical passenger car based diesels you would find in the smaller SUVs. Which is not a great thing. As every gas motor, even the one in smaller cars/suvs/and trucks will have reasonable engine braking capability.

Color it however you want but in my experience, a diesel SUV (without engine brake) has better engine/gearing slowing capabilities than the same SUV with a gas engine. Same for a Chevy 2500 diesel with engine brake over a F150 ecoboost gasser.

[pteck]

Originally Posted by mojo

Color it however you want but in my experience, a diesel SUV (without engine brake) has better engine/gearing slowing capabilities than the same SUV with a gas engine. Same for a Chevy 2500 diesel with engine brake over a F150 ecoboost gasser.

So a single persons perceived impression, trumps an accepted engineering fact? The word anecdotal comes to mind.

Perhaps you don't know how to properly use an engine for braking? There's been noise here about "limiting rpm", even for a diesel engine, that I highly suspect user error. Engine brakes can and should take advantage of the larger rpm band of an engine. Many users are afraid to rev their motor on the way up a hill, let alone on their way down, to take advantage of gearing. Gearing allows a motor, leverage! Use it to your advantage, the motor will be just fine.

F150 ecoboosts, have transmissions with tons of gears. More engine braking is a downshift away. This is true of your diesel with a properly fitted engine brake, too.

[mojo]

My experience is as anecdotal as your opinion.

Six years towing with the F150 and experiencing close to overheating transmission (6 gears), close to overheating engine and brakes has shown me that even in 2nd gear on a 14% downgrade, a diesel with engine brake does a better job. And that's a fact!

[Tuco]

Originally Posted by pteck

This is wrong, and continues to incorrectly persist a perceived advantage of diesel.

The addition of a diesel engine brake only brings to parity what a gas motor already has. Without getting into the inner workings, a gas motor inherently has engine braking by way of the throttle plate to block the free flow of air through the motor. A diesel does not have any such thing, and has to be fitted with one in order to provide adequate engine braking capability. It’s done a bit differently, but a diesel without the addition of an engine brake will not adequately slow a heavy rig downhill. This would be all the typical passenger car based diesels you would find in the smaller SUVs. Which is not a great thing. As every gas motor, even the one in smaller cars/suvs/and trucks will have reasonable engine braking capability.

This is exactly what i was talking about as far as "Smoke and Mirrors" in the other thread. Do you honestly believe that drawing a vacuum behind the throttle plate is why a gas engine has engine braking? When you put your hand over the end of a vacuum cleaner hose is the motor working harder or does its speed increase indicating more rpm and less load? Both types of engines are four cycle engines (intake, compression, power, exhaust). What actually gives gas and diesel engines their ability to engine brake is their compression ratio. Diesel engines have a higher compression ratio than their gas counterparts. As you have stated before a diesel engine has no throttle plate. Each time the compression stroke comes around it has to compress a full air charge thus creating the work seen as engine braking. In a gas engine on each compression stroke the vacuum created in the manifold means less air is drawn into each cylinder to be compressed. This reduces the effective compression ratio of the engine. Which also reduces the amount of work seen as engine braking. The faster the engine turns the higher the manifold vacuum becomes thus reducing work done per compression cycle. That is not the case in a diesel engine. Now add in the exhaust brake which pressurizes the exhaust manifold. This causes the engine to work to push the air out of the cylinder on each exhaust stroke. This adds even more work seen as engine braking. The faster the engine turns the higher this exhaust pressure becomes. Which means more work is done at higher rpm. So to sum things up. A diesel engine has more engine braking than a gas engine in a normally aspirated configuration. Adding the exhaust brake into the mix on a diesel means you have added a second cycle to the equation which is seen as additional engine braking.

[pteck]

Originally Posted by mojo

Color it however you want but in my experience, a diesel SUV (without engine brake) has better engine/gearing slowing capabilities than the same SUV with a gas engine . Same for a Chevy 2500 diesel with engine brake over a F150 ecoboost gasser.

Originally Posted by mojo

My experience is as anecdotal as your opinion.

Six years towing with the F150 and experiencing close to overheating transmission (6 gears), close to overheating engine and brakes has shown me that even in 2nd gear on a 14% downgrade, a diesel with engine brake does a better job. And that's a fact!

Hey, no surprise a diesel WITH engine brake will do a great job. That was never the point of contention.

[mojo]

Originally Posted by pteck

Hey, no surprise a diesel WITH engine brake will do a great job. That was never the point of contention.

OK, I used to tow with a V8 Touareg gasser with a 19' & 25' AS. It did fine with 6 speeds and a sport mode. Then switched to a Touareg V10 Turbo diesel, same transmission, with a 25' & 27' AS. Same car, different engines. The diesel outperformed going up and down grades by far, with less downshifting and rpm's. Just another anecdotal experience... or fact.

[pteck]

Originally Posted by Tuco

This is exactly what i was talking about as far as "Smoke and Mirrors" in the other thread. Do you honestly believe that drawing a vacuum behind the throttle plate is why a gas engine has engine braking? When you put your hand over the end of a vacuum cleaner hose is the motor working harder or does its speed increase indicating more rpm and less load? Both types of engines are four cycle engines (intake, compression, power, exhaust). What actually gives gas and diesel engines their ability to engine brake is their compression ratio. Diesel engines have a higher compression ratio than their gas counterparts. As you have stated before a diesel engine has no throttle plate. Each time the compression stroke comes around it has to compress a full air charge thus creating the work seen as engine braking. In a gas engine on each compression stroke the vacuum created in the manifold means less air is drawn into each cylinder to be compressed. This reduces the effective compression ratio of the engine. Which also reduces the amount of work seen as engine braking. The faster the engine turns the higher the manifold vacuum becomes thus reducing work done per compression cycle. That is not the case in a diesel engine. Now add in the exhaust brake which pressurizes the exhaust manifold. This causes the engine to work to push the air out of the cylinder on each exhaust stroke. This adds even more work seen as engine braking. The faster the engine turns the higher this exhaust pressure becomes. Which means more work is done at higher rpm. So to sum things up. A diesel engine has more engine braking than a gas engine in a normally aspirated configuration. Adding the exhaust brake into the mix on a diesel means you have added a second cycle to the equation which is seen as additional engine braking.

Not bad. But you're not seeing the full picture.

You're taking a single piston, and the compression stroke, in isolation. Have you considered what the piston right over from it is doing? It had already compressed air, but now that compressed air is returning that energy right back into the down stroke of that piston. Net resistance, is not that much! Which is why a diesel needs to be fitted with a jake brake or some method of additional compression resistance.

True, a gas engine brake works on vacuum for net resistance.

A diesel without any engine brakes.... look below

Originally Posted by mojo

OK, I used to tow with a V8 Touareg gasser with a 19' & 25' AS. It did fine with 6 speeds and a sport mode. Then switched to a Touareg V10 Turbo diesel, same transmission, with a 25' & 27' AS. Same car, different engines. The diesel outperformed going up and down grades by far, with less downshifting and rpm's. Just another anecdotal experience... or fact.

So this is apples to apples to you? The fact that your Toureg has 10 pistons and 5L worth of drag vs. a gas 3.5L V6 has nothing to do with it. So a 4cyl diesel without engine brake must be better than a 6cyl gas engine at braking? And overheating must be a gasoline thing?

A conflation of parameters leads to wrong perceptions.

[mojo]

Read again. Comparison of a Touareg gas vs. Touareg diesel without engine brake.
There is no 3.5L V6 mentioned.