No matter what kind of gimmicks car manufacturers offer, there are always those people who are looking to purchase their vehicles "by the numbers." With the current fullsize diesel truck offerings from Dodge, Ford, and GM, there are certainly a lot of numbers.
Power and torque numbers, payload capacity, towing ability, fuel economy, and dollar figures all factor into the equation when buying these vehicles. We decided to take a look at the '08 Ford F-250 6.4L compound turbodiesel and see how it measured up on the scales, the dragstrip, and the dyno-as well as look at nonperformance numbers like price and fuel economy.
We decided to see if we could...
We decided to see if we could get another power number for the truck on Westech's dynamometer. Unfortunately, we were running into the same gear-changing problem. Westech, however, was able to do an acceleration test through the gears to see what the peak power would be but could give no torque reading. This time, power peaked at 306 hp at the wheels, so we felt safe that we were in the 270-300 rear-wheel-horsepower range.
Usually, the first questions people ask are, "How much power does it make?" and "How much does it cost?" Although the final numbers aren't in yet, expect that an '08 Ford F-250 like our test vehicle will be priced around $53,000. What you get for this price, though, is an advertised 350 hp and 650 lb-ft of torque, which gets us back to our power question.
We wanted to see how close we could come to the advertised power number, so we took the truck to the Redline Diesel Performance dyno event in Corona, California, and put it on the chassis dyno to find out how much power we were putting to the ground.
We had no way to lock the truck in any gear, so the dyno operators were having trouble keeping it from downshifting into a lower gear or upshifting into Fifth gear-either one would create a spike in the power graph, skewing our readings. On the one clean run we did get, the truck made 274 hp and 620 lb-ft of torque at the rear wheels. The torque seemed high to us, so we also ran the truck over at Westech, where we ran into the same problem. This time, we couldn't get a decent torque number at all, but horsepower pulls were in the 270-300 rear-wheel range, so it's safe to say Ford's advertised numbers are pretty close.
Next was a trip to the dragstrip, which answered the question, "How fast is it?" The truck felt pretty fast to us, and with the compound turbo arrangement, boost was 20-plus psi even at part-throttle. Dragstrips don't lie, and "felt pretty fast" would soon be converted to real-world performance numbers.
 We went to Redline Diesel...  We went to Redline Diesel Performance in Corona, California, for its inaugural dyno day. Even though our Ford kept trying to upshift or downshift, we came away with 274 hp and 620 lb-ft of torque once the rollers stopped. |  The factory routing of the...  The factory routing of the intercooler pipes left us wondering if we could get some easy power gains. The intercooler pipe is nearly flat when going through the radiator core support. |  On the dyno, there wasn't...  On the dyno, there wasn't a hint of smoke or particles of any kind-even at full song. |