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Wind is the kicker. That's when you need horsepower. I had the same experience when I picked up a 14' x 7'wide enclosed motorcycle trailer for my dad. It has 7' of standing room inside and the front is just flat across. It isn't that heavy and my 4.0 Ranger did great in town--this was in Detroit and I was bringing it back an hour south of Indy. Anyway, fine in town. But when I started up the ramp and got to about 50 it just ran out of power. I drove it at 3,000rpm in 4th for 350 miles and it got about 12mpg. It's a lot more revs than I feel comfortable with and the semis going past have a low pressure area beside them that sucks the trailer toward them, which is fun. Sure you can do it.
Power is power. But let's compare a schoolbus with a Ranger. My 18,000 bus can pull a 6% grade at 45mph with the engine at 2,500rpm in 5th gear. It's 185hp with an engine that weighs 1,300# and a massive cooling system with like 3" radiator hoses.
A 4.0 SOHC Ranger pulling a 14,000# trailer will need 4,500rpm to make 185hp. You've only got 2 gears though. You take off in first (which might not be possible with a 14,000# trailer), shift it a redline and then it will be at 39mph and 3600rpm. If you hit the bottom of the hill at 4,500rpm it should be keeping up with the bus on the way up.
The main problem is that the 4.0 doesn't have enough gears if you are going to use it for that much weight. It has 2 gears to use on the hill and the bus has 5 with the first being 9.04-1 and a 4.78-axle. A 3.40 first and a 3.55-axle means your clutch is probably going to be on fire, and in reality, the bus will be long gone if they start together at the bottom. Next, both engines have to get rid of the waste of 185hp heat. The Ranger was in no way meant for that with it's little plastic radiator and tiny cooling system. You keep it at maximum torque for that long and the heads will wrinkle up and spit the gaskets out right before the pistons start swapping holes.
Old school buses did use passenger car engines. But they had upgraded cooling systems, very low and slow gearboxes and the engines were derated. Even the modern bus engines are derated. The 200hp 5.9 Cummins in a medium-duty truck/bus makes 300+hp in the Dodge pickup passenger car rating. If you wanted 300hp in a medium-duty truck you would put in a 10 liter engine.
Power is power. But let's compare a schoolbus with a Ranger. My 18,000 bus can pull a 6% grade at 45mph with the engine at 2,500rpm in 5th gear. It's 185hp with an engine that weighs 1,300# and a massive cooling system with like 3" radiator hoses.
A 4.0 SOHC Ranger pulling a 14,000# trailer will need 4,500rpm to make 185hp. You've only got 2 gears though. You take off in first (which might not be possible with a 14,000# trailer), shift it a redline and then it will be at 39mph and 3600rpm. If you hit the bottom of the hill at 4,500rpm it should be keeping up with the bus on the way up.
The main problem is that the 4.0 doesn't have enough gears if you are going to use it for that much weight. It has 2 gears to use on the hill and the bus has 5 with the first being 9.04-1 and a 4.78-axle. A 3.40 first and a 3.55-axle means your clutch is probably going to be on fire, and in reality, the bus will be long gone if they start together at the bottom. Next, both engines have to get rid of the waste of 185hp heat. The Ranger was in no way meant for that with it's little plastic radiator and tiny cooling system. You keep it at maximum torque for that long and the heads will wrinkle up and spit the gaskets out right before the pistons start swapping holes.
Old school buses did use passenger car engines. But they had upgraded cooling systems, very low and slow gearboxes and the engines were derated. Even the modern bus engines are derated. The 200hp 5.9 Cummins in a medium-duty truck/bus makes 300+hp in the Dodge pickup passenger car rating. If you wanted 300hp in a medium-duty truck you would put in a 10 liter engine.
