Re: Towing capability
After years of truck driving, and many years riding shotgun with Dad, there's NO substitute for displacement and horsepower.
Had a situation one afternoon hauling concrete, '66 White, 165 hp Cummins and Spicer 5+4 transmission, loaded with 7 cubic yards of concrete I grossed 52,000#. I followed an old lady out of town, she was driving 5 mph under the speed limit, passing her was not possible, fortunately she turned off the US route down a side road and then I had a chance to flat-foot it, but with the slight hills when I got to the big S-curves 7 miles out of town I was only going 35-40 mph, had dropped gears on uphill grades I never realized existed, normally I slowed from 55 mph to 50 for those S-curves.
That's all horsepower, or more correctly lack of hp and conservation of momentum. The newer trucks with 208 hp V-8 555 Cummins I had to slow down from about 63-64 mph to 55, even drop a gear in the Power-sapping Allison suto trans.
We had a guy on another forum that bought a million mile Volvo semi-tractor with a 450+ hp 60-series Detroit diesel, Super 10 Road-Ranger, needs a new clutch. He was determined to put a 6-71 Detroit in the truck to pull his 14,000# RV, Combined driving experience of those telling him to NOT do that was around 50-60 MILLION miles. The 6-71 was referred to as a 238, meaning 238 hp in it's most powerful tune. 305 V-6 is just over half that, with many fewer gears. Your gross weight will be just slightly less. Cruising speed much less.
Thing that impresses me the most is the fact todays's 500-600 hp trucks can run so fast and get such good mpg, 6-7 mpg is common. My old '79 White RoadBoss II with 320 hp 903 V-8 Cummins, 6-speed Spicer trans and 4.44 rear gears got about 4 to 4.25 mpg summer and 3 to 3.25 mpg winter on blended fuel. Grossed 70,000# most of the time, geared to run 67 mph at 2500 rpm, which was my usual cruising speed. I got a speeding ticket and slowed down to 62 mph and mpg really didn't improve. I forget the name of the regional carrier, but followed one of their trucks for a while on I-70 out west running 95 mph down a grade, 80 mph up the other side about 6 yrs ago. Made a quick trip to just outside Boston a week ago, most trucks running 65 mph. Funny story, took a detour from my normal route thru Chicago, jumped off onto the Skyway, My wife's first impression exactly the same as mine 35 years ago, " All that toll money to go over a Big Purple Bridge?" Ran I-94 right thru downtown, on July 4th morning, saved over an hour and almost half a tank of gas.
|