One of the most fun projects I worked on at Ford was the E4OD/4R100 transmission for the off road racing community. We built transmissions for a Class 8 truck, which later became a Trophy Truck. They ran in SCORE and BITD events. The transmissions we sent were not THAT far from stock, but they did have some parts that were a lot stronger than stock. Sometimes we used prototype parts that were in testing for future model years (as seen above). One 500 mile off road race showed similar wear to many thousands of miles of durability testing.
My part of this effort was tuning, wiring, and hands on help for the team. Our premier team was Enduro Racing. Their two drivers were Dave Ashley and Dan Smith. They were multiple race and championship winners before we were involved, and only got better with our help.
Their truck was an F-150. It had a stock frame per the class rules. Quite a bit was added to it. It had about 36” of suspension travel. It had a 351 based race engine making probably 650 hp. We replaced the C6 with an E4OD.
The transmission never shifted automatically. We had an electrical switch to shift it. Press it forward to upshift and pull back to downshift. At the first test we had to reverse the switch. On hard braking it was too hard to pull the tiny switch backwards! Lesson learned.
We also didn’t allow the converter to lock automatically. We tried that at first, but there are some terrains that MUST have the converter unlocked. Washboard surfaces are one of these. The tires make and break traction several times per second. With the converter locked the truck twisted a driveshaft into a pretzel. Another lesson learned. We installed a lockup switch so that the driver could lock the converter when the road surface allowed it.
Before the E4OD top speed was about 120 mph. You might think that’s fast enough on a desert trail. It was fast enough to win sometimes. We wanted to win more than sometimes. With overdrive and a lockup torque converter we measured this truck on a beach at 154 mph. That was a closely guarded secret when it happened almost 20 years ago. By now I expect most Trophy Trucks can do this. Nobody was even close back then.
As one of the team support people I got to go to a lot of races. One memorable race was the 1994 Baja 1000. Dave and Dan led most of the race and won it by a pretty good margin. I spent about 24 hours in one of the chase trucks on the radio keeping up with our truck and the competition, and keeping the team owner up to date on where everybody was.
One race that I wasn’t at had a failure. The transmission coolers were in the bed of the truck and two large electric fans. The fans quit and the support team couldn’t fix them. They had to run without transmission cooling. The trans temp gauge only went to 320 F. It was pegged for almost the entire race. They kept going and won their class.
After the race the trans was shipped back to us in Michigan for a teardown. The teardown showed no major problem with the transmission. The fluid (Mobil 1 Synthetic ATF) was a bit dark, but not black. The solder had melted out of each of the solenoids and was sitting in the pan! Solder melts at 450 F. The trans had to be at least that hot for that to happen. So when people on the boards tell me their trans is going to fail if it goes above 200 F I don’t believe them!
Later the team moved to a Ford built 5.4L 4V with a TorqShift transmission. I was already off doing other things and never worked on that truck.