Adding Diff Covers And A Transmission Pan Cooler To Upgrade A 2000 Ford

Juan Ochoa uses his truck practically every day and on weekends he asks it to step up and do the tough job of hauling his camping trailer out to the beach, desert, mountains or wherever his young family cares to go to escape the city.

But Juan often doesn’t like the things he sees on his transmission temperature gauge while climbing hills on hot days. And he knows the front and rear differentials are getting a workout too. On flat highway with no load, Juan usually sees about 180 degrees on the temp gauge. Around town in stop and go traffic the temps climb to 196. Put a load on the truck and head up a long hill and the temperature quickly climbs to over 210.

PML diff covers offer a lot of improvement over the factory covers. First of all, they are made out of aluminum and that means they dissipate heat better than the steel factory units. Second, they carry more diff fluid so that helps keep temperatures down. Third, they have fins on the cover that add cooling. But there’s more! A magnetic drain plug allows for oil changes without removing the cover, as you have to do with the stock one. A fill hole and level hole make those oil changes very easy. The machined gasket surface allows for a secure seal using either RTV or a factory reusable gasket and the thick gasket flange (3/8-inch thick) will not bend when the bolts are tightened. The thick wall, sand cast construction actually adds strength to the differential housing.

Juan also opted for the PML transmission pan. In addition to many of the same benefits as the diff covers (better heat dissipation due to material and design, thick gasket flange, etc.) the transmission pan from PML carries a full 8 extra quarts of oil compared to the factory pan.

But covers and a pan weren’t the end of the upgrades. No, Juan also got a transmission cooler with a built-in fan from Flex-A-Lite to really keep the temps down. He had Cory mount the cooler up near the radiator and ran the lines down to the factory lines.

We met Juan at B&C Auto Repair in Vista, California, where Cory LaBouve spun the wrenches and got the 7.3L Power Stroke-equipped Super Duty ready for the road. Check out what it takes to beef up a truck for heavy hauling.

After using the truck for a few weeks after the installs, Juan reports great success. Instead of seeing trans temps of 210 and more when towing the truck is now rock solid in the area of 180 degrees. When not towing the truck’s transmission came down from 196 to 168. Basically the transmission is 30 degrees cooler all the time compared to what it was before the cooler/fan and trans pan. DW

1 To really ensure that the transmission stays cool while towing uphill in hot weather, Juan got himself a 26,000 G.V.W HD remote cooler/fan from Flex-A-Lite.
2 Cory LaBouve at B&C Auto Repair in Vista, California, got to work on the truck. First, he removed the bolts securing the stock rear differential cover. And then used a scraper to get the cover loose. One of the disadvantages of the factory pan is there’s no drain plug. The PML pan not only has a drain plug but it also has a level plug (when oil runs out it’s full) and, of course, a filler plug.
3 Using ACDelco engine sealant (RTV), Cory laid a bead all the way around the gasket flange of the differential pan. A steady hand helps to get the cover lined up without smearing the RTV all over the place. New Allen head bolts, supplied by PML, were then used to secure the new PML pan.
4 PML’s diff cover has a magnetic drain plug with a copper gasket. A little snug “oomph” is all that’s needed to seat the bolt. After giving the excess RTV some time to harden, Cory neatly removed it with a razor blade.
5 Royal Purple’s 75W-150W Max Gear lube was used to fill the differential. The fill hole is easy to get to if you have an automatic machine to pump the oil up to the diff.
6 The transmission oil pan was the next target on the list of things to do. First, the oil was drained from the pan. Then, Cory removed all the pan bolts. The factory pan was removed and drained into a recycling container.
7 The transmission pan from PML holds a full 8 additional quarts of oil and has cooling fins on it. It’s stronger than the factory stamped steel pan and dissipates heat better. Hardware is provided because longer bolts are necessary to get all the way through the extra thick gasket flange. It can be installed using automatic transmission fluid compatible sealant or a factory gasket. Juan chose to use a new factory gasket.
8 Again, an electric impact was used to get all the bolts snug, but not tight.
9 On to the front differential. Once all the bolts were out, Cory used a putty scraper to break the seal and let the lube out. Isn’t it crazy that there’s no drain plug? PML solves that issue.
10 Here’s a good look at how much bigger the PML pan is in comparison to the factory front diff pan.
11 Cory likes to use ACDelco engine sealer RTV on diff pans. It’s very stout.
12 It’s a bit of a tight fit with the steering arm in front of the differential, but it can be done. Again, the hardware is supplied by PML and there’s no room for a power wrench here.
13 More Royal Purple lube was used in the front differential.
14 Here’s a good look at the front cover before the RTV had cured. We trimmed it later.
15 Next came the Flex-a-Lite Transmission Cooler. After removing the factory grille to gain access the cooler/fan combo was mounted right in front of the radiator with some straps. The cooler can be mounted anywhere and the fan can run in either direction.
16 The straps used to mount the cooler aren’t exactly pretty, but they are very effective and can’t be seen once the grille is back on.
17 Two barbed fittings were used to tie the cooler into the existing system. Here Cory cinches down the fittings, making sure to use pipe thread sealant to help prevent leaks.
18 Running the lines between the cooler and the connections made on the factory transmission cooler lines came next. Cory fished the rubber lines between the frame rails to the cooler.
19 Figuring out where to run the lines is the trickiest part.
20 Cory ran two hose clamps on each end and he put them in opposite positions. Here’s the fitting all tightened down. This connection is never going to leak.
21 Underneath the truck, Cory wound the hose through a variety of obstacles to get to the factory lines.
22 Cory split some more hose for use as extra protection. This is an area where the hose could wear over time so extra protection is a good idea. Several zip-ties were then used to hold the hose protector in place.
23 Truck owner Juan got back into the action when it was time to put the grille back on.
24 Cory added a hose to his oil-filling machine to reach all the way to the back of the engine compartment where the transmission filler tube is located.
25 Royal Purple Max ATF transmission fluid was used to fill the trans with the new pan.

B&C Auto Repair


PML Covers

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