PROJECT LML

The custom-machined billet EPC Fooler from Deviant Race Parts of Hayden, Idaho, will plug right into the stock solenoid and slip back into the valve body bore and block fluid from signaling the solenoid with current pressures. The fooler will trick the solenoid into bumping pressure up to that much higher 250 psi all the time and spiking to 280 psi on shifts. The beauty behind all of this is that the increased line pressure will help hold higher-than-stock power levels without affecting shift quality. Since the pressure on shifts isn’t increasing much, you shouldn’t notice much, if any, change in shift firmness, so you maintain that nice, smooth acceleration the Allison is known for. The EPC Fooler can be installed without dropping the valve body from the transmission and installation will only add about ten minutes to a standard transmission filter service and fluid exchange.

When this truck was purchased, it came with excellent service records on the Carfax report, so we knew exactly when the last transmission service had been completed (76,000 miles). With the odometer cresting 121,000 miles, it was nearing the recommended 50,000-mile full transmission service with a new internal and external filter change, along with some fresh fluid. What better time to install the EPC Fooler, right? We picked up a case of the recommended automatic transmission fluid at the local parts house and called out to Merchant Automotive of Zeeland, Michigan, for a complete transmission service kit that comes with a new spin-on filter, internal filter, deep Allison fluid pan and custom-machined internal Filter Locks. Since we’ll be towing in the hot summer months up and down some long mountain passes, upgrading to the deeper pan and increasing fluid capacity another 3 quarts could really help control fluid temperatures. Plus, this MA trans service kit is super inexpensive, so it’s one of those no-brainer upgrades. With it and the EPC Fooler, you’re at less than $200 in parts and the benefits from helping extend a stock transmission’s lifespan could help pay for itself in no time.

With the transmission upgrades and service taken care of, while under the truck we opted to service the transfer case as well. The four-wheel-drive transfer is often forgotten and overlooked on every truck owner’s maintenance schedule, but with only 2 quarts of fluid in it and an easy fill and drain port, there really is no reason you can’t keep up on fresh fluid changes every 50,000 miles as well. The fluid that drained out of this truck’s transfer case wasn’t as bad as some we’ve seen, but it was definitely due. While the

 By removing the one 8mm bolt and keeper that holds the EPC Solenoid into the valve body, the solenoid can be popped out of its bore. The billet machined plug supplied by DRP simply slips over the end of the solenoid and can be reinserted into the...

 It’s time to install the new internal filter and put the pan back on. This was the perfect time to spend a little extra money and get the factory Allison deep pan and filter kit from Merchant Automotive, which increases fluid capacity for better...

 With the solenoid and fooler back in the valve body, the original keeper and bolt is reinstalled as well. The O-ring on the solenoid is enough to hold it snug into the fooler. The stock transmission runs at 80 psi line pressure all the time and will...