SoCalDesertRider wrote: The problem is when the 400 lb-ft @ 4000 rpms engine only puts out 200 lb-ft at 2000 rpms and the manufacturer puts in 3.55 gearing instead of 4.56 gearing. The engine doesn't reach those high power producing rpms until the road speed is much too high for pulling a big trailer on a curvy road. I'd rather have the 400 lb-ft at 2000 rpm and I don't care what it produces at 4-6000 rpm because I have no need to operate it at that engine speed or road speed.
In the above scenario, the truck would just run a gear or 2 lower. I would add that many gas engines have fairly flat torque curves with variable valve timing, cam phasing, etc. The vast majority of modern gas engines in trucks make 80% of their torque by 2000- 2400rpm.
400 lb-ft x 2.32 x 3.73 = 3461 lb-ft at the rear wheels.
400 lb-ft x 2.32 x 4.30 = 3990 lb-ft at the rear wheels.
400 lb-ft x 2.32 x 4.88 = 4529 lb-ft at the rear wheels.
400 lb-ft x 1.52 x 3.73 = 2268 lb-ft at the rear wheels.
400 lb-ft x 1.52 x 4.30 = 2614 lb-ft at the rear wheels.
400 lb-ft x 1.52 x 4.88 = 2967 lb-ft at the rear wheels.
400 lb-ft x 1.15 x 3.73 = 1716 lb-ft at the rear wheels.
400 lb-ft x 1.15 x 4.30 = 1978 lb-ft at the rear wheels.
400 lb-ft x 1.15 x 4.88 = 2244 lb-ft at the rear wheels.
400 lb-ft x 0.86 x 3.73 = 1283 lb-ft at the rear wheels.
400 lb-ft x 0.86 x 4.30 = 1479 lb-ft at the rear wheels.
400 lb-ft x 0.86 x 4.88 = 1679 lb-ft at the rear wheels.
400 lb-ft x 0.67 x 3.73 = 1000 lb-ft at the rear wheels.
400 lb-ft x 0.67 x 4.30 = 1152 lb-ft at the rear wheels.
400 lb-ft x 0.67 x 4.88 = 1308 lb-ft at the rear wheels.
I included the 4.88 ratio because once Ford starts offering the 6.2 in the F450/550 trucks, it will likely come with the 4.88 ratio. Pulling the same load, those trucks will be one gear higher in the transmission with the 4.88's versus the 3.73's.
I'd like to see them offer the F350DRW with the 6.2 and 4.88's. That would eliminate the need for the diesel for just about anything the F350 chassis is capable of pulling.
Well I am sure glad I found this thread! Thanks so much for the info SoCalDesertRider. I am getting a FORD 350 Crew Cab Long Bed to haul a 5000lb truck camper and occasionaly town my 4,500lb boat.
I think I am going gas just had to decide on either the 3.73 or 4.30's. Sounds like the 4.30's would be the appropriate choice, correct?
I also agree the Dodge interiors are the BEST and the front end cap of the new Fords are the WORST!
Thanks,
Mr. E
MackinawMan wrote: Thanks for the report...these "newer" gas engines are more than capable of towing heavy loads pretty darn well from what I've gathered reading the various reports.
I agree with the poster on here that said diesels may have jumped the shark. More than likely the next truck we buy will be a gasser.
Depends on perspective. I don't consider 11K heavy.
The new diesels are rated north of 20K.
There are NO gas motor pickups currently available that will even come close to that.
For that weight, I'll take an F-550 with the 30-valve V10 & 5.38 gears. Diesels have jumped the shark.
John and Elizabeth (Liz), with 3 nutty cats
My beloved St. Bernard, Marm, lost him 1/2/12
Current rig:
1992 International Genesis school bus conversion
If you get the 3.73 and run it in 4th while towing or carrying heavy when needed, you'll be putting more torque to the wheels than the 4.30 in O/D and you won't have to listen to it howl like a banshee all day when it doesn't need the rpm. I owned one Cummins with a 4.10 and 5spd that ran 2500rpm at 70mph towing or not. Too many gears in a transmission to choose from to limit yourself to O/D at high rpm. Did it again with 4.56 in my '05 Hemi powered 2500HD. Just my humble been there, done that opinion.
'10 F250 XLT CC SB 5.4L 5spdTS 3.73
ex '95 Cummins,'98 12v Cummins,'01.5 Cummins,'03 Cummins; '05 Hemi
'07 KZ Jag 28JFSS.
The 6.2 seems to be a good motor and the new tranny is just like the allison, works very well, we have lots of them at work. As to whether or not the gasser will pull x amount of trailer on the highway, yes they will. I had a 2006 gm 6.0 gasser pulling a 9000 gross 5ver. Did it pull it on the highway yes it did, was it enjoyable, or relaxing? no it was not. The biggest problem i had was in the mountains going to my camping spots there were times I could not get the engine rpm's up high enough to build enough HP to pull the trailer, there was one instance where i had to stop shift into 4lo to climb the hill out of the camping area. I have been to the same area with my diesels and same 5ver with no issues at all. Having more HP at a lower rpm does have its advantages.
It's funny to hear it explained that way because personal experience tells me otherwise.
I grew up on a farm, and performed many of the "hauling" chores with a gasoline powered tractor for many years. You had to be on the brakes almost constantly to keep it under control towing loaded forage wagons down hills.
Later on we got a diesel tractor that was basically the same model as the gasoline one I'd been hauling with for years. This tractor would hold the load on the hills hardly touching the brakes at all.
I went from riding the brakes to touching them once or twice, same hill, same load. Only difference was the diesel engine.
Idle the diesel back, and it was like throwing out an anchor. Idle the gasser back, and it would coast on and on and on.
Dad said it was because the diesel engine had so much more compression, that the engine braking effect was greater.
So much more compression had nothing to do with it. The energy to compress the cyliner is almost all returned on the expansion of that air on the down stroke. The diesel tractor may have different gear ratio's or something else that made it different, but it was not the compression. If the hills were short it may have been something as simple as the rotating mass of the engine having a flywheel effect.
I can take you for a ride down a hill in my Cummins diesel powered truck and turn off the exhaust brake leaving the smart controller on that locks the torque converter and show you that the engine has little or no hold back without the exhaust brake on. I know it is no nice to tell someone their dad was wrong, but!!!
Somewhere in a Fifth Wheel - Where it does not Snow
400 lb-ft x 2.32 x 3.73 = 3461 lb-ft at the rear wheels.
400 lb-ft x 2.32 x 4.30 = 3990 lb-ft at the rear wheels.
400 lb-ft x 2.32 x 4.88 = 4529 lb-ft at the rear wheels.
400 lb-ft x 1.52 x 3.73 = 2268 lb-ft at the rear wheels.
400 lb-ft x 1.52 x 4.30 = 2614 lb-ft at the rear wheels.
400 lb-ft x 1.52 x 4.88 = 2967 lb-ft at the rear wheels.
400 lb-ft x 1.15 x 3.73 = 1716 lb-ft at the rear wheels.
400 lb-ft x 1.15 x 4.30 = 1978 lb-ft at the rear wheels.
400 lb-ft x 1.15 x 4.88 = 2244 lb-ft at the rear wheels.
400 lb-ft x 0.86 x 3.73 = 1283 lb-ft at the rear wheels.
400 lb-ft x 0.86 x 4.30 = 1479 lb-ft at the rear wheels.
400 lb-ft x 0.86 x 4.88 = 1679 lb-ft at the rear wheels.
400 lb-ft x 0.67 x 3.73 = 1000 lb-ft at the rear wheels.
400 lb-ft x 0.67 x 4.30 = 1152 lb-ft at the rear wheels.
400 lb-ft x 0.67 x 4.88 = 1308 lb-ft at the rear wheels.
I included the 4.88 ratio because once Ford starts offering the 6.2 in the F450/550 trucks, it will likely come with the 4.88 ratio. Pulling the same load, those trucks will be one gear higher in the transmission with the 4.88's versus the 3.73's.
I'd like to see them offer the F350DRW with the 6.2 and 4.88's. That would eliminate the need for the diesel for just about anything the F350 chassis is capable of pulling.
Well I am sure glad I found this thread! Thanks so much for the info SoCalDesertRider. I am getting a FORD 350 Crew Cab Long Bed to haul a 5000lb truck camper and occasionaly town my 4,500lb boat.
I think I am going gas just had to decide on either the 3.73 or 4.30's. Sounds like the 4.30's would be the appropriate choice, correct?
I also agree the Dodge interiors are the BEST and the front end cap of the new Fords are the WORST!
Thanks,
Mr. E
If I were buying a new Ford with the 6.2 engine, the truck would DEFINITELY have the 4.30 gears. That said, if all you're pulling is 4500 lbs, I'm sure the 3.73's will do just fine.
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