I want a Sterling grill for my 3500

 

actually the reason your volvos pulled better than a dodge pickup is all in the gearing, which I didnt realize thats what you were talking about. Of course you couldnt put a 5spd and a 5.9 in front of 80,000 pounds and expect it to do very well, I thought you were just complaining about the "lack" of power they had, so I was illustrating how thankful for the power we get these days. if you put an 18 speed behind 220 horsepower it can still pull those big loads, a 6 speed medium duty wont do as well. But make no mistake, these trucks will still pull. the transmissions arent designed to pull class 8 loads, but the gearing in the axle is lower and the whole suspension is beefier to handle the extra weight. Anyway, If i pass you on the road in my unloaded 03, ill be sure to give you a wave

 

That's a light load. My double hay trailers were pulled with a CTD and a 6sp Eaton for years. I replaced it with the U500 with a little 130 hp engine!
Gearing is 14.93/8.23/4.47/2.46/1.52/1.0

 

That would sure make for a LONG DAY.Had a Bad enuff day 2day driving a junky cornbinder with a DT530 and 8LL. In my humble opinon when it comes to HP well not really HP but TQ.. The more you got the better your day is gonna be. Also the more productive more loads per day, more tons per load and plus you arent flogging the heck out of the motor just to get up a ant hill.

 

Yes gearing is a huge differnce in pulling heavy loads. And a semi is going to have lower gears, for one, the tire size differnce.. They have to have lower gears. But....A transmission still has a 1-to-1 ratio.-gear... like on a 6sp manual. I think its 5th. The RPM's and MPH go up the same!!! On a semi, theres one gear that is a 1-to-1 ratio. So pulling a hill with both trucks in their 1-to-1 ratio gear, you should be able to tell power differnce!!!! Sorry the 300+ horse the trucks are suppost to have don't feel like it!!! Take a ol 12v with 165hp from factory, add a fuel plate, injetors, and timming. They feel about as stong if not stronger than the new 300+hp trucks!!!

 

now youre just talking out your ***, the old 12 valves made a lot less torque and hp and were geared higher or the same, usually with 3.54s or 4.10s. A tractor with a 1:1 top ratio might run 45 mph at 2100 rpm wot, but its producing peak hp and torque probably down to around 12 or 1400 rpm, what the 5.9 peak out at, 2600 for hp and 1400 for torque. so youre revving it higher to make similar power. you can lug the big trucks a lot lower. also like you said, tire size, weight, even amount of tires. you're expecting too much out of a medium duty truck - for it to pull the same way a class 8 tractor does.