Ford E40D Transmission Upgrade - Dieseltech

Positioning the transmission...        read full caption Positioning the transmission dipstick tube is one of the trickier parts of the trans-swap procedure. It's a two-person job-one person lowers the tube from the tight, limited-visibility, firewall-area of the engine compartment, while the other person positions the tube inside the receiver tube from below the truck.

Our Power Stroke is equipped...        read full caption Our Power Stroke is equipped with a small, factory transmission fluid cooler. Jose and David disconnect its lines and cycle new fluid through the system to flush out any of the burnt transmission fluid still inside the cooler and/or cooler lines. We stepped up to a bigger cooler a few months after this installation was complete. See the sidebar "Cool Stuff" (page 128) for more details.

Advanced Technology Lubricants...        read full caption Advanced Technology Lubricants (ATL) offers this 5-gallon bucket of its Synthetic Automatic Transmission Fluid (PN 810640: $321.98), and it's more than enough for filling a transmission as big as an E4OD. Pouring fluid from the bucket into any smaller container is the best method for filling the torque converter with the ATL product as well as adding the fluid to the new tranny.

It's important to note that a MaXimizer E4OD's shift points will not be any different from the factory-programmed intervals. E4OD transmissions are controlled by the PCM, so despite the improvement in valvebody operation, the transmission's shift points won't change unless modifications are made in the processor.

Our new Truck Master torque converter features a 6-lug, billet-steel cover as well as a triple-disc clutch pack and steel stator. With our truck's stock 7.3L turbodiesel, the converter's flash stall is around 1,300 rpm-a 30 percent reduction, as the stock converter stalls at 1,800-2,000 rpm. According to Lowell Poff of TCI, there's a major efficiency benefit in going with such a low-stall converter. "Our transmission and torque converter work well for this type of truck (used primarily for towing) because with the higher fluid pressure and low stall speed of the converter, and subsequent lower engine rpm, the converter has less potential to slip. This helps keep heat to a minimum and increases the longevity of the transmission unit. Heat is by far the number-one killer of a transmission," Lowell says.

The last order of business is a final road test and pressure check. The test shows that line pressure in our new MaXimizer E40D is well within TCI's accepted pressure ranges for this transmission, a major improvement over the numbers we logged in our initial road test.

Cool Cool Stuff Stuff
Our tow vehicle is often subject to mega-mile trips through some seriously hot territory in the Western states (California, Nevada, and Arizona). As we mentioned earlier, heat is one of the biggest killers of any automatic transmission.

The truck's new TCI MaXimizer E40D transmission (along with its high-torque converter) performs flawlessly, with smooth and firm upshifts and distinct downshifting when coming to a stop. The truck handles the West Coast freeways and grades at 65-70 mph without any problems. We switch the Overdrive to "off" for the steeper grades, which is recommended for heavy towing. The new transmission allows our BD exhaust brake to work much better when compared to its performance with the original tranny. It is the MaXimizer E4OD's definitive downshifts on deceleration that make all the difference.

After driving and towing the truck for about two months (approximately 2,500 miles) with the new transmission, we decided to drop the trans fluid to get an idea of how things were going with the new tranny during its break-in period. Everything looked OK by us, and the transmission fluid was still blood red. At the time of inspection, we decided to add a bit of cooling insurance by installing TCI's High-Tech Racing Performance tranny cooler (PN 823800: $99.96) and a "Max-Cool" diesel aluminum fluid pan for the E4OD transmission (PN 498010: $453.70). The new pan was filled with TCI's "Max-Shift" transmission fluid (PN 950600: $71.40 for 3 gallons) when the installation was complete.

While these parts are not required, we strongly suggest you consider adding them during the tranny swap. They will definitely help keep the tranny cooler, which will enhance its performance and extend its life.

This new cooler is massive...        read full caption This new cooler is massive when compared to the puny, factory cooler. The TCI piece will help keep our new tranny's temp within a safe operating range at all times.

This TCI "Max-Cool" aluminum...        read full caption This TCI "Max-Cool" aluminum trans pan is beyond trick. The black, powdercoated pan doesn't require a gasket or sealant to secure it to the transmission. Instead, the pan's rail surface is channeled, and a rubber O-ring is used to provide a leak-proof connection. The pan holds 7.5 quarts more than the OEM pan and also features heat-dissipating fins for optimum cooling.