Mark's under-three minute presentation on the HD GM truck is well done, but he slipped a bit on the riff about customers saying they really don't want more torque.

It's kind of like the Vegan telling me he really doesn't miss having the Surf N Turf that much.

His pitch also went too light on GM's new gas V8s, something that all of the big 3 have a lot riding on.

Today's half ton trucks have become so muscular that HD's will need constant upgrades in performance and luxury to keep buyers wanting the difference between 1/2 ton and the big trucks---enough to pay the big difference in price (and operating costs).

Maybe GM can take market share back from Ram.

"Mark's under-three minute presentation on the HD GM truck is well done, but he slipped a bit on the riff about customers saying they really don't want more torque."

Bottom line it is torque to the tires that makes a truck go. I suspect that with a 10-speed transmission the GM and Ford products may be able to get more torque to the ground on average through the power band than Ram's 6 speed. The road tests will be interesting.

I really like the GMC Sierra HD, including the new 6.6 gas V8. My wild guess is that GM will be updating the Duramax in about 1-2 years with more power. With the new 10-speed 'Allison', that is not torque limited in any gear (first in segment), GM might still stay out front in the next PUTC HD challenge. The Sierra might be tied for last place in luxury interiors, along with Silverado and Ford, but seems to make up for that in powertrains, new features, and capability. We don't know yet, but it am guessing that the 6.6 gasser will not test out as well as the new Ford 7.3, but will likely outrun the 6.4 Hemi. I can't wait to see the competition with the 'gassers'.

I'll take a dependable long-living Six Speed trans (or a manual) over a fussy expensive 10 speed any day. Even more true when that transmission is coupled with a torquey gas or diesel engine.

I drove trucks for a living in my youth and most of them were either 3-speed or 4-speed manuals. Five speed boxes came along later. We never felt like we were under-gunned because the HD trucks of that day had a splitter (2 speed Hi-low case) that gave you great options in the mud/snow and suitable choices on the paved roads.

Today's 10 speed autos attempt to address the much higher vehicle speeds we have on the Interstates. Trucks in my day---esp. those carrying a big load---simply were not being operated at vehicle speeds higher than 45-55 mph.

Today you've got perfect fools on the highway driving 65-75mph on the Interstate with tires, brakes and chassis that are entirely unsafe at that speed carrying loads that have never seen a scale. Unsafe. Most states are clueless when it comes to licensing private vehicles of this sort.

Whew! At least GM will have one good looking truck to offer!

Papajim, you make a good point on the 6-speeds, my gut feeling matches yours that the new 10-speeds may not be as durable as some of the current 6-speeds, or the manuals...and I certainly expect that we will see more 'gear hunting' with the new 10-speeds.

That's the best HD truck on the market and the future PUTC HD winner!

Love the looks of that truck AT4.

The 6.6L gasser with new 6 spd should be a pulling machine. GM gave us more power and the durability of the 6.0L.

UGH!!!

@papa:

Whatever Governal Motors says you need---you want.

"I'll take a dependable long-living Six Speed trans (or a manual) over a fussy expensive 10 speed any day. "

That a pretty bold assumption and shows a lot lack of faith in GM egineering

"I drove trucks for a living in my youth and most of them were either 3-speed or 4-speed manuals. Five speed boxes came along later. We never felt like we were under-gunned because the HD trucks of that day had a splitter (2 speed Hi-low case) "

So getting 10 rations from a 5 speed with a 2 speed rear end is much better than getting 10 speeds from one package with 40 more years of engineering in that package. As I recall, most of those trucks had less than 200 horsepower. That could contribute a lot the life of a transmission.

"Today's 10 speed autos attempt to address the much higher vehicle speeds we have on the Interstates. Trucks in my day---esp. those carrying a big load---simply were not being operated at vehicle speeds higher than 45-55 mph."

Yeah! Let's go back to the days of Smokey and the Bandit with a national 55mph speed limit.

"Today you've got perfect fools on the highway driving 65-75mph on the Interstate with tires, brakes and chassis that are entirely unsafe at that speed carrying loads that have never seen a scale. Unsafe. Most states are clueless when it comes to licensing private vehicles of this sort."

You are absolutely correct that 75mph is much more dangerous than 55mph but I don't see us going back so the question is how we cope with it. The explosion of big pickups with monster loads has me concerned. On the other hand, from what I hear private vehicles that leave the factory heavy like motorhomes have a very good safety record. At the very least, the DMV should offer some safety courses. I know that my insurance company offed me a discount if I took a safety course but I haven't found one in my area yet.

Walt. It's all about load---not horsepower.

Regarding safety, this is a topic for the states to handle, and some of them already do a good job of it. Regarding highway speed, it's about load and conditions. I am seeing guys on the highway almost every day who have poorly secured loads and trailers that are probably not fit for the job.

You got a bit snarky reacting to my comment about ratios (not rations). Engines that make a lot of torque at low rpm are much less dependent on the 10 speed or 8 speed trans.

Engines that perform best at high rpm, the DOHC 4-valve motors especially, need the extra ratios to equal the performance of the engines like the 6.0 vortec and the Cummins diesel.

Any time you want me to instruct you about this further let me know.

@papa

"Engines that perform best at high rpm, the DOHC 4-valve motors especially, need the extra ratios to equal the performance of the engines like the 6.0 vortec and the Cummins diesel. Posted by: papajim | Mar 1, 2019 9:49:50 AM"

Who here has heard of any engine that performs better at idle?? Anyone? All engines perform best and deliver the most power at a high RPM (relative to fuel type of course), now some engines have a higher RPM operating range (generally OHC) but having a closer spread of ratios in the trans AKA gears delivers the engine output more efficiently regardless of engine design.

So dont make excuses for Gm when there is no excuse for not offering a 10-speed with the gasser when it does for the Diesel.

@papa:

Whatever Governal Motors says you need---you want.

Posted by: redbloodedxy | Mar 1, 2019 8:07:00 AM

LOVE
FORD!

Posted by: redbloodedxy | Nov 6, 2018 9:27:19 AM

I wonder where you draw the line on what Ford says you need.

HAHAHA! Hypocrite!

"You got a bit snarky reacting to my comment about ratios (not rations). Engines that make a lot of torque at low rpm are much less dependent on the 10 speed or 8 speed trans.

Any time you want me to instruct you about this further let me know.

Posted by: papajim "

My Cummins with a 6 speed Allison feels like it dies every time it upshifts to fourth or fifth gears. It desperately needs at least one more gear. Maybe your experience is different but to avoid that sensation of lost power you need a wide power band with diesels have not been know for though some of the new ones are doing better.

And, if you don't need 8 to 10 speeds why do you like the 2 speed axle so much?

The new GMC HD truck line-up has become the most desirable trucks in the segment. Tough looking exterior, ultra performance drivetrains, highest towing capacity and luxury interiors. The new SILVERADO HD's are a close second place. Ram too has great new HD's. Ford will certainly need to keep pushing their dated trucks into the fleet markets. unning hugh discounts to

And running hugh discounts to attract private customers.

"The new GMC HD truck line-up has become the most desirable trucks in the segment. Posted by: GMSRGREAT | Mar 1, 2019 11:36:08 AM"

The expert opinion of a Gm kool-aid drinker with no factual anything behind it.

"Ford will certainly need to keep pushing their dated trucks into the fleet markets. unning hugh discounts to Posted by: GMSRGREAT | Mar 1, 2019 11:36:08 AM"

Another expert opinion from the same shill who brings Ford fleets sales up any chance he gets yet has never produced where his knowledge on those sales come from. He did however say his employer buys hundreds of Chevy fleet trucks....

@fullsize

Every engine has a "sweet spot" of its own. Someday after getting some experience of your own driving cars and trucks you'll learn about this first hand.

Until then you can just keep reading my comments if you want to smarten up.

Actually the effective rpm range of an engine is governed by valve timing. Since valve timing is.controlled by the camshaft the camshaft controlls rpm range. This led to cam phasers to help widen the rpm range.

@ Jennifer N

U better not buy any of the bug 3 auto makers then bc they all have taken money from taxpayers.

Hint: any big corporation doesn't care about the public. All they care about is money🤑🤑🤑

I currently own 3 GM vehicles and am completely satisfied with them

And I'll continue to buy them bc they have treated me great and have put least amount of money in them after the sale

Looks like we're seeing a backup file. Jennifer disappeared along with my last comment or two.

One of my complaints on my old LML Duramax was that there wasn’t enough gears to get good use out of the engine braking. It doesn’t even start downshifting until 50mph or so. So I’ve been looking forward to these 10 speed diesels since they were first rumored. I know some here are scared of progress, but I seriously can’t wait. I’ll probably get a 2019 Super Duty in the next week or so, but I have my eye on the 2020 AT4. We will see what the 2020 Ford has when they give us more info.

Another expert opinion from the same shill who brings Ford fleets sales up any chance he gets yet has never produced where his knowledge on those sales come from.

Posted by: FullSize_only | Mar 1, 2019 11:52:49 AM

Sorry, I don't post links. Sound familiar?

When can you buy it

Ford offers choices, consumers make decisions. As a result Ford sell more full size pickup trucks and completly dominates HD pickup truck sales.
As for link posting by a particular GM shill he/she/shim posts them it is suits purpose, but is snarky when challenged for supporting data when it does not.
So borish.

Ford offers choices, consumers make decisions.

Posted by: GM Blows Chunks | Mar 1, 2019 6:54:44 PM

You never thought that comment through well enough. GM offers choices and sells more trucks as a result. Capisce?

When your premise is flawed and postion untenable go to narrow quote out of context argument.
What I wrote is completely true.
Your response is to a different and irrelevant question not asked.

@alex

You make a good point about the engine braking. Where I live it's flat as a table top for miles and miles. Where I grew up, engine braking would be very important.

Again. Good point.

The power band of all ICE is governed by valve timing, AND head flow, flow efficiency, displacement, bore to stroke ratio, rod to stroke ratio, and fuel type.

Cam phasers control the overlap which broadens power bands.
An OHC doesn’t mean high rpm, it means generally a higher flowing cylinder head that can support higher rpm.

But torque and horsepower are not interchangeable.
HP is a product of torque and the constant is 5252 rpm, meaning below that point at any HP peak there is more torque available than HP, above the point the reverse.

The gear ratio spread is idealized to keep the engine between the HP peak and the TQ peak at every full throttle up or down shift.

“Bottom line it is torque to the tires that makes a truck go.”
Funny, the lead Engineer on the new GM HDs said a similar thing about getting the torque to the ground. Too bad GM trucks bend tie rods in 4Lo under power. Just ask the USBPC about their beefed up toe rod ends. At least the ones in AZ have them.

"An OHC doesn’t mean high rpm..."

@James

I admire your technical knowledge, but on the (above) point I'll reply with a question for you---Can you name the last time a car qualified for the Indy 500 with a pushrod engine?

Hint: I think you'd have to go back to the 1980s for the answer. Even then, the Indy rules committee allowed the GM V6 teams a huge advantage in boost and cubic inches for the 3.8 V6 stock block to be competitive at the Speedway.

I'm scratchin' my head and the only other exception I can think of is NASCAR Cup racing today where you have pushrod V8s with huge valves and crazy cams (cars that are unable to idle at all) running on alcohol, at engine speeds near 10k RPMs on the track.

The advantage of an overhead cam engine is the lower mass the valve spring has to move to close the valve. This lower valve train mass has at least two possible advantages. Lower parasitic losses due to less valve spring strength needed. Higher rpm capability with the same strength valve springs as a push rod engine.

Some truck manufactures,up until very recently, offered one size vehicle and achieved a certain level of success in doing so. Another truck manufacturer actually offered choices which has resulted in it becoming the truck sales King over that past number of years.

The advantage of an overhead cam engine is the lower mass the valve spring has to move to close the valve

@JTT

Please cite your source for the above statement---you could be right, by the way.

1---If two valve stems are identical in weight (and diameter) and one's on a OHC head and the other's on a pushrod head, where is the difference in mass?

2---Since we were discussing large gasoline powered low-RPM V8s in HD trucks how does a discussion of engine speeds north of 5000-6000 RPM really address the topic?

I think most trucks in this category are in their sweet spot between 1.5k to 3.5 or 4k rpm.

Some truck manufactures,up until very recently, offered one size vehicle and achieved a certain level of success in doing so. Another truck manufacturer actually offered choices which has resulted in it becoming the truck sales King over that past number of years.

Posted by: GMSRGREAT | Mar 1, 2019 9:16:43 PM

Are you ashamed of what you are trying to say or just afraid you will be corrected one more time. Or you can not remember the names of the companies you are talking about.
I wish I could make up stuff as funny as this.

The advantage of an overhead cam engine is the lower mass the valve spring has to move to close the valve
@JTT
Please cite your source for the above statement---you could be right, by the way.
1---If two valve stems are identical in weight (and diameter) and one's on a OHC head and the other's on a pushrod head, where is the difference in mass?
2---Since we were discussing large gasoline powered low-RPM V8s in HD trucks how does a discussion of engine speeds north of 5000-6000 RPM really address the topic?
I think most trucks in this category are in their sweet spot between 1.5k to 3.5 or 4k rpm.

Posted by: papajim | Mar 1, 2019 9:26:11 PM

Source = Common sense and knowledge.
The valve train is more than the valve itself It is everything between the camshaft and the valve. A pushrod engine has a lifter and a push rod and a rocker arm. An OHC engine uses a cam follower and a rocker arm generally speaking. You will lose at least the mass of the push rod.
I was just discussing the differences in pushrod and OHC engines. The advantages of the different engine designs for what rpm ranges is another discussion.

Just listen to the GM losers talking about selling the most. Most of what? Yall gotta add everything together including some old Pontiacs to try and make that claim. Nobody else does that but you bunch of losers. Truth is that the F-Series sells the most FULLSIZE TRUCKS EVER. About 100 yrs now and counting. THE BEST NEVER REST. Should I sign this by Johnny Doe?????

I think most trucks in this category are in their sweet spot between 1.5k to 3.5 or 4k rpm.

Posted by: papajim | Mar 1, 2019 9:26:11 PM

papadim I am glad you brought that up. That is exactly the rpm range that Ecoboost engine really shine hence why people like them. Also remember pushing your torque to lower rpms limits your max horsepower. That is why horsepower numbers alone can be almost meaningless.

Actually the ford F-series is the best selling vehicle in the world. And no one in the world sells more trucks than Ford.

The advantage of an overhead cam engine is the lower mass the valve spring has to move to close the valve. This lower valve train mass has at least two possible advantages. Lower parasitic losses due to less valve spring strength needed. Higher rpm capability with the same strength valve springs as a push rod engine.
Posted by: Just the truth | Mar 1, 2019 9:08:22 PM

The disadvantage of an overhead cam valve-train is that there is FAR MORE moving mass and energy required for it to function. The crankshaft has to transfer power through multiple timing chains (2 very long timing chains and 2 short timing chains) that rotate 4 cams (as opposed to 1 cam in a pushrod engine), the cam phasers require a lot of oil flow and pressure to correctly function which increases demand on the oil pump, and those 4 cams are pushing down on twice as many valve springs to actuate twice as many valves (in the case of a 32-valve V8). That's a lot more moving mass than a single cam and 16 lifters/hollow pushrods, and 16 valves.

-------------
The valve train is more than the valve itself It is everything between the camshaft and the valve. A pushrod engine has a lifter and a push rod and a rocker arm. An OHC engine uses a cam follower and a rocker arm generally speaking. You will lose at least the mass of the push rod.
I was just discussing the differences in pushrod and OHC engines. The advantages of the different engine designs for what rpm ranges is another discussion.
Posted by: Just the truth | Mar 1, 2019 9:42:01 PM

Yet the 32-valve DOHC V8 will have double the number of valves, rockers, and lash adjusters. Plus the huge difference in moving mass of 4 cams vs 1 cam, 2 very large timing chains vs 1 very short timing chain, 4 cam phasers vs 1 cam phaser, etc. Those 4 cams riding on 4 times as many bearings, resulting in much more frictional losses. The very large timing chains require very large timing chain guides, which introduces yet more frictional losses. Plus that huge number of moving parts at the top of the head, including 4 cam phasers, requires an oil pump that requires much more oil output to work correctly and last. It's not a huge different, but it's still enough to where DOHC V8 rarely offers any advantage in fuel economy. A good example of this is when Ford first introduced the 2015 F-150 5.0, it struggled to match a 2015 Chevy 1500 6.2 in fuel economy, while the 6.2 made more power and moved a truck weighing more.

@JTT

please stay up the rest of the evening and keep baiting the GM guys. In the morning I'll sort through your drivel and decide whether or not to reply to any of it.

Your comments about ecoboost engines are foolish. Not even Ford has put an ecoboost in a 2500 or 3500 truck--which in case you did not notice was the whole point of this volley. The fact that Ford is yapping about its 7.3 gasser is proof of my point.

Don't forget. Stay up and write.

I admire your technical knowledge, but on the (above) point I'll reply with a question for you---Can you name the last time a car qualified for the Indy 500 with a pushrod engine?

Hint: I think you'd have to go back to the 1980s for the answer. Even then, the Indy rules committee allowed the GM V6 teams a huge advantage in boost and cubic inches for the 3.8 V6 stock block to be competitive at the Speedway.

I'm scratchin' my head and the only other exception I can think of is NASCAR Cup racing today where you have pushrod V8s with huge valves and crazy cams (cars that are unable to idle at all) running on alcohol, at engine speeds near 10k RPMs on the track.
Posted by: papajim | Mar 1, 2019 8:56:13 PM

The pushrod V8 has been alive and well in the racing world. Just not in oval racing. The Corvette Racing team has had a ton of success with a Pratt & Whitney pushrod V8 exactly as you described. The Camaro GT4.R had some really big early success in IMSA 2 years ago with Stevenson Motorsports before he got out of the racing business, ending its season early. There are a couple teams running pushrod V8 powered Camaro GT4.R's in the upcoming IMSA season.

The advantage of an overhead cam engine is the lower mass the valve spring has to move to close the valve.
Posted by: Just the truth | Mar 1, 2019 9:08:22 PM

This lower valve train mass has at least two possible advantages. Lower parasitic losses due to less valve spring strength needed. Higher rpm capability with the same strength valve springs as a push rod engine.
Posted by: Just the truth | Mar 1, 2019 9:08:22 PM

This "advantage" in RPM capability is so high it is not applicable in anything other than a very expensive sports car. Ford's trucks and Mustang generally do not have a redline anywhere close to this RPM. The exception being the GT350 and GT500 but that's a very different case.

Like HD Ramking pointed out the downside of that high revving valvetrain is that there are much bigger parasitic losses in a DOHC setup. The crank shaft is turning an oil pump that is doing a lot more working in a DOHC engine and the crank shaft is transferring more energy to turn all those cams and phasers.

Actually the ford F-series is the best selling vehicle in the world. And no one in the world sells more trucks than Ford.

Posted by: Just the truth | Mar 1, 2019 10:24:24 PM

The F-series is not a single model vehicle, therefore you can not claim it to be the best selling vehicle.

Yep exactly. Pushrod engines do have an advantage in energy lost in operating the vavletrain.

The one thing which the OHC engine lacks which the pushrod engine has is the mechanical advantage of the valve train itself. For the same cam profile you can open the valve higher quicker with a OHV engine. This is beneficial for power and that’s what we like. It’s also beneficial for power lower in the RPM range. And for a truck that’s what you want.

What I find humorous is that some guys on here are so eager to champion DOHC engines but they suddenly get giddy when they find out Ford has a pushrod V8 on the way after decades of avoiding them at all cost.

OHC/pushrod... is whatever the engine you’re talking about Class leading in performance, capability and fuel economy? Ford has shown they can make really good engines in high configurations. I rented a V10 (OHC) F650, filled it to the max to haul all my crap interstate, while doing 75mph and towing a car on a trailer behind it. It held 6th gear most of the time. Going from Idaho Falls to Park City, UT that was some high Elevation and mountain climbing too. Averaged 6.5 mpg. A neighbor rented a Penske Freightliner diesel and averaged 8.5 mpg without a car trailer and speed limited at 65! At today’s fuel prices, I spent only $8 more in fuel (not accounting for a drop in mileage on the Penske if it did have a car behind it, and if it could go faster than 65).

I’m sure Ford’s pushrod 7.3 will be even more capable, but that doesn’t mean the V10 was bad at all. It also doesn’t mean Ford should have used pushrods on the Coyote, and it doesn’t mean the GM 5.3 is bette than the Ford 5.0. Ford’s 6.2 is also a really good motor. I’m not knocking GM motors either, I’m just saying they both have advantages. If the 7.3 will be used for electrification at some point, then pushrod really does make sense. There seems to be little benefit of high rpm power on medium duty trucks.

@alex

Try talking to the shops that specialize in engine re-manufacturing. Nobody wants to handle the Ford modular engines because they're stinkers. A few shops used to specialize in (Ford mod) cylinder heads but that's less true now.

On the other hand go to the same shops and you'll discover there's a lively market for old Chevy SBCs and the current-gen GM V8s. This is not to say that GM doesn't have its share of stinkers but not so much among the truck engines.

And that's not even touching the Ford powerstroke diesels. Ford has not had a great V8 engine since they killed off the Windsor engines more than 20 years ago.

Yet another reminder for the dim of mind.

1 Cummins is the best truck to own.
2. Durmax is the best truck to perform the task.
3. Ford, is well.. how can I say it without making dumb people mad?

No one said you had to have much intelligence to live in the Florida panhandle.

@Jeff Alan

In my area Panhandle is a noun. In your neighborhood it's a verb.