F450 vs Ram 3500 DRW tow vehicle
So the wife and I are moving to the full time RV lifestyle. We just purchased a 42' toy hauler this weekend, with a GVWR of 20K#. Now I'm looking at a tow vehicles. I'm considering either purchasing a...
Forum Discussion
Grit dog wrote:
I don't disagree with you, theoretically, however, realistically, unless all the online calculators are wrong (and I'm not busting out the statics and dynamics book tonight), 24-28k gross, 96 sf frontal area at 70mph is average around 230-250hp to overcome air drag and rolling resistance.
That's average. No head or side winds, no grades, etc.
Yes, the new Powerstrokes make impressive HP down low, but it's not quite as rosy as it seems, IMO.
And you're talking roughly 1600rpms vs 2000rpms on a F450 with 4.30s vs 3.55s. You're not going to hold 10th gear with 3.55s with any large trailer at 70mph except in a vacuum.
So down it shift a gear or 2 and then pops back up when the wind stops for a second, then down when you go up the other side of a dip in the road and back up when you go down the dip, so then yo ulock it in 8th gear and there you are...
Bobtail or light trailers, sure 3.55s will hold top gear all day, likely. And drop a couple/3/4 gears for the BIG loads.
I agree that deep gears aren't needed except for BIG loads and even at that, with 10 cogs, there's a gear for every condition.
But if you're tugging around the stuff that requires a 450 chassis, why not have the most snort behind the skinny pedal?
Bet you're not saving appreciable fuel unless running light weight, but then that's not what the truck is made for with 4.30s although it'll still do 10x better than my old 6 speed with higher gears.
I agree. If the truck is going to loaded most of the time or even half of the time then it is best to get the shortest gear ratio possible for better fuel economy and less stress due to higher cylinder pressures on the engine. Not only that, but the performance factor is another abstract benefit as well. However, if it is rarely going to tow then taller gears will be the best option for fuel economy. I would like to think that if someone is going to step up to an F450, then they are likely going to pulling a load behind it most of the time. Otherwise they would get an F350.
