Adding programmers, exhausts, cold-air intakes, suspension lift kits, bigger tires, and larger diameter wheels looks killer on today's heavy-duty diesel pickups. A 3/4- or 1-ton truck just looks right with all the added burliness and muscle-not to mention the authoritative exhaust note from all those angry ponies. With today's technology, it is quite easy to add 100 hp, or even 200 hp, with over-the-counter bolt-on modifications. The transmission is where the problem arises. Factory diesel transmissions are far stouter than ever, right off the assembly line; but that's still not enough. With a computer tuner set on "kill," and a stock transmission trying to harness it all, slippage and parts breakage were sure to follow.
We visited with our friend, Nic Germano, and glanced over his wounded '01 Ford F-250's transmission. Plenty of power, coupled with a stock automatic transmission and 39-1/2-inch tires, and Nic's 4R100 said adieu. Luckily, a gracious Northern California dealer put the transmission on the warranty list and handed Nic a fresh in-the-crate replacement. After conversing with Matt Bozarth at ATS Diesel Performance, we had a pile of parts to install with the new slush box that was sure to help. We then added to that a full synthetic lubrication allotment from Amsoil. Check out how it all went together.
From The Driver SeatAfter pulling out of Irvington Wheel and Brake, we gave the transmission some miles to get well lubricated and warmed up to operating temperature. While driving around town, we toyed with the Co-Pilot's settings and tried the torque converter lockup speeds between 5 and 35 mph, and found the speed the truck liked best without lugging the motor down. With a few acceleration "tests" in near triple-digit weather, we found the new ATS additions to the transmission to be just what the doctor had ordered. Of course, the E-Power Programmer let the 7.3L diesel really chew up the rear tires under heavy right-foot activity. Perfect! The transmission's shifts were crisp, there was plenty of power, too, and it was all being protected by the synthetic lubrication technology of Amsoil. We only got the thermostatically controlled fan on the trans cooler to come on once during the whole test. Safety at last.