Forum Discussion
127 Replies
4x4ord wrote:
Cummins12V98 wrote:
4x4ord wrote:
If the 440 hp rating of the Powerstroke is not SAE flywheel hp what else would it be?
I have no idea, they sure did not use SAE on the tow ratings except for the 450. That's why I am asking.
GM is very clear about SAE Flywheel horsepower. Seems they always did well with "less power".
I believe the reason GM was able to do so well racing up the mountains had a lot to do with the Allison gear ratios. The initial Eisenhower pull was done under the guidelines of GM. They knew exactly what torque the Duramax could deliver to the rear axle in 3rd gear. (It would be approximately 3100 lb ft of torque) They also knew that at 3000 rpm (max power rpm of the Duramax) they could do 56 mph. The F350 could put 3600 lbft of torque to the rear axle in 3rd gear but would only be capable of 48 mph @2800 rpm in 3rd gear. They needed to load the trailer such that on a 8% grade (if that's what the Eisenhower pass grade is) the load would require just under 3100 lb ft of torque on the truck's rear axles. (If the Ford shifts to 4th the rear axle torque would drop to about 2900 lbft of torque) If Ford was conducting the test they would have eanted a steeper hill or heavier trailer to prevent the Allison from coming out of second gear. The new diesels make enough torque that they won't be as easy to find holes in the gear ratios.
I did some calculations using a Engine RPM site RPM calculator. If I use a 3.73 rear ratio and 1.52 3rd gear ratio for a Ford I get 46 mph at 2773 rpm.
But if I use a 4.10 rear ratio (called the holy grail by many for towing) and 1.15 4th gear ratio I get 56 mph at 2808 rpm for the Ford.
So if Ford were to supply the correct rear ratio for their test truck I do not see the problem compared to the GM Duramax.
In fact if I use a 3.37 rear ratio and 1.41 for Allison 3rd gear
I only get 54 mph at 3020 rpm. So I would say the Ford should have the advantage. Do not forget the Ford advertises more HP than the Duramax.- I would think all this means is less MPG. The current Dmax is powerful enough and has the HP required why do more.
Cummins12V98 wrote:
4x4ord wrote:
If the 440 hp rating of the Powerstroke is not SAE flywheel hp what else would it be?
I have no idea, they sure did not use SAE on the tow ratings except for the 450. That's why I am asking.
GM is very clear about SAE Flywheel horsepower. Seems they always did well with "less power".
I believe the reason GM was able to do so well racing up the mountains had a lot to do with the Allison gear ratios. The initial Eisenhower pull was done under the guidelines of GM. They knew exactly what torque the Duramax could deliver to the rear axle in 3rd gear. (It would be approximately 3100 lb ft of torque) They also knew that at 3000 rpm (max power rpm of the Duramax) they could do 56 mph. The F350 could put 3600 lbft of torque to the rear axle in 3rd gear but would only be capable of 48 mph @2800 rpm in 3rd gear. They needed to load the trailer such that on a 8% grade (if that's what the Eisenhower pass grade is) the load would require just under 3100 lb ft of torque on the truck's rear axles. (If the Ford shifts to 4th the rear axle torque would drop to about 2900 lbft of torque) If Ford was conducting the test they would have eanted a steeper hill or heavier trailer to prevent the Allison from coming out of second gear. The new diesels make enough torque that they won't be as easy to find holes in the gear ratios.53 willys wrote:
You know what they say if you can't afford a real truck you'll have to settle for a Dodge
I would say few of us need a real truck for hauling around our RVs and that's why we buy our little pickups. I would much rather tow my RV with a GM, Ford, or Ram diesel than have to use a real truck.R. Walter wrote:
53 willys wrote:
You know what they say if you can't afford a real truck you'll have to settle for a Dodge
Nothing better to do than troll, huh?
New member with 15 posts and a new F350, which came with a case of blue oval koolaid.- I like the gm trucks a lot, that being said all three would be fine in my book. In the years to come, when I get another truck, I'm going to drive all 3 and pick the best one. It may not be an gmc, but change can be good. We have had all 3 diesels in my family, Ford, 6.9, 7.3, 7.3 turbo, Dodge 5.9 12 valve, 6.7 now, Dmax 6.6. All have been good trucks. Parents now own a dodge 6.7 and they love it. In fact I plan to take it on my next camping trip if they so kindly allow and leave my truck with them. I have not driven the 6.7 yet but will say I have ridden in it and it's quiet and rides good for a 1 ton truck. I told my wife if we do borrow it, she may get spoiled cruising up the grades.....she may want me to go back to diesel....lol well but then reality steps in and I almost got this one paid for, so I will be keeping this one a long time! Anyway these threads always evolves into a pi..ing match and they should not be. Everybody be happy for what you drive, we live in a blessed nation, for how long nobody knows but we live far better then most. Enjoy the ride.
- I read this thread from start to finish.
I love all the comical comments. Everybody has their Favorite truck.
I started with a 96 dodge cummins single cab. moved into a 99 quad cab 4X4 Bombed the **** out of it. Still own it however it lives in another state and when I go to that other state it starts right up with the first turn of the key. Still my favorite truck. My Alaska truck was then a 07 classic Duramax 6.6 diesel/Allison Truck was ok but I was continually having to put Ball joints and tie rods yes I drove it hard. But the DW decided she did not like the Chevy D/A for some reason. I bought a 13 ram 3500 4x4 6.7 CCSB CUMMINS WITH THE Asin tranny. This truck rides like a luxury car and can pull buildings down. when in normal towing up grades the transmission is seeking the sweet spot all the time. I shift it to manual and leave it in 4th gear and it will power up any grade and accelerate. I am bonding very well with this truck and the DEF is no issue at all. I cannot speak with any useful opinion on ford diesels because I have never owned one. however my father who is a lifelong die hard ford owner who has a 2012 CCSB 3500 4x4 ford loves my 13 ram enough after riding with me that he is looking at the new rams for a purchase. yes I pull trailers with my truck and a 3500 is a bit of a overkill for what I use it for. But I could not be happier with my 2013 with 35000 miles and 0 issues except a few recalls. Just my 2 cents worth. Not trolling.
Have a great day. spud1957 wrote:
Here's a little explanation regarding SAE certified HP.
http://www.sae.org/certifiedpower/details.htm
Are Ram's numbers bogus? They use J1995.
http://www.autoguide.com/auto-news/2015/08/are-the-2016-ram-hd-s-output-figures-bogus-.html
Did you read your second link?
Form the referenced link.
However, just because Ram uses a different procedure does not mean its claimed figures are spurious. According to SAE, the J1995 standard is:
Intended for use primarily by engine manufacturers that supply engines to other companies for installation in applications where the engine manufacturer may not control induction and exhaust system design or the speed at which the powerplant runs.
Since Ram buys its diesel engines from Cummins, this rating standard makes sense. Everything appears to be on the up-and-up.
“We were the pioneers in the large displacement turbo diesels in heavy-duty trucks,” said Cappa. Ever since Chrysler introduced the original 5.9-liter Cummins 27 years ago, he said they’ve used the same exact test procedure, J1995, so it’s not like the folks in Auburn Hills decided one morning they were going to try to game the system by using a different procedure from the rest of their competitors.
Driving his point home, Cappa noted, “Our engineers truly feel the 1995 power ratings provide a more direct reference for comparing heavy-duty engine performance.” This is because these hard-working trucks can be outfitted in countless different ways, with equipment like dual alternators, power-takeoffs and so on, all of which leads to varying parasitic losses, which Cappa said are more accurately taken into account by the J1995 standard.
Ford “We’re using 1349 for our engines,” said Mike Levine, truck communications manager at Ford, a standard they believe is more rigorous than J1995.
GM But where does General Motors, the third biggest player in the heavy-duty truck segment stand on this issue? According to Tom Read, the powertrain communications man at GM, all of their engines, unless otherwise noted, are rated using SAE J2723, a third procedure, which is arguably the most trustworthy one.
But back to test procedures. When asked if there was any estimable percentage difference between J1995 and J1349, Pollak said, “There’s so many variables, so much involved, it would be hard to make any kind of comparison like that.” Unfortunately, there’s no real way to stack them against one another.
“Each of them are equally valid, equally fine,” noted Pollak. However, “Unless you go through our certified power program … we have no oversight,” so conceivably an automaker could make nearly any claim they wanted. “And that’s one of the reasons we started our certified power program,” added Pollak.
All of that to say GM is the only one using the SAE J2723 at the time of this article on Aug 28, 2015.53 willys wrote:
You know what they say if you can't afford a real truck you'll have to settle for a Dodge
Nothing better to do than troll, huh?- You know what they say if you can't afford a real truck you'll have to settle for a Dodge
