I wouldn't say that the PPE cover has a shape close to the OEM. The bottom corner of the PPE cover comes close to a 90° angle and extends very far from the mounting surface. It's also worth noting that the fins in that area run horizontally which may inhibit oil flow. The OEM cover has a smooth contour that follows the ring gear and no fins at all. When Ford does use fins on their diff covers, the fins typically run in the direction of oil flow and stay away from the ring gear as seen in the picture posted below.

 

PPE makes high quality / engineered products, I have no doubt it will perform better than OEM just like their transmission pan. It also holds 1/2 quart more fluid than OEM. Temps are the information I’m after not opinions.

 

More than likely you will be perfectly fine. Just don't fall into the trap that all aftermarket parts companies are good at engineering. Some probably are and some definitely aren't.

I am an engineer in the aircraft industry and we refer to those guys as the B team. The OEM guys have the resources to do things right.

 

It will be interesting to see, the temps will tell
the full story. If an Aeration and or churning is truly an issue temps would go up, not down.

According to their literature.

”Each cover comes with extra gusseting for improved strength, as well as a curved design with built-in oil scrapers that help prevent churning. The cover comes standard with fill and drain plugs, and the drain plug is magnetic in order to get as much debris out of your F150's gears and bearings as possible. The cover also includes a 1/8" NPT port on its right side that allows you to install a temperature sensor for better monitoring”

I plan on installing a temp sensor in the NPT port to get accurate data. Initially I’ll just use my infrared laser to compare outside cover temps. Not apples to apples, but it’s my only option right now. The “b” team sure did a hell of a lot better with the transmission pan vs the “a” team. A 14° drop in transmission temps is pretty significant just for a pan.

 

FYI, don't read the cover with the temp gun. Measure the housing in the same location both times. Different surface colors/finishes will have different emissivity values and will give you different temp readings.

 

when you say housing can you be more specific? The back or side of the differential? I guess j could pick an area close to the cover and measure if there is any difference.

I measured the cover today just to see what it read after a 45 min drive / 95 ambient, nothing stressful and it 143 F.

 

The fun starts. I measured on the back of the diff in multiple areas. I will update this post soon. 👍

Edit - I need to do some more testing under various conditions. The unit took roughly 4.2 quarts. I took a 30 min drive, there was lot of traffic, but about 15 min of highway in downtown Atlanta. I’m seeing a 33 degree drop in temps!

The back of the diff measured 137 yesterday, now I’m 104! That’s impressive. I’m also noticing less “clunking” that would exhibit itself from time to time from the rear. Tech estimated about 2.5 - 3 quarts was rained. I wonder if the rear was under-filled from the factory?

 

I know it takes 1-2 hours of driving for my engine and transmission to reach full operating temp. I would imagine that it would take even longer for the rear diff to come up to temp. Temp readings that are taken too soon are significantly impacted by changes in fluid capacity and driving style.

 

I can’t comment on that. This is definitely not the case for engine oil & transmission. I find they are both at full operating temps within 15 minutes. I monitor them via the OBD2 / Ford PID’s. Both measurements were done after 30 min of driving. Again, this is not actual oil temp. This is the backside of diff case temps. I do not have a way to measure the oil temps at this points. Nonetheless, this is a significant improvement.

 

What is the concern regarding the rear diff? It is probably one of the least problematic mechanical systems on the whole truck.

Have you had issues before?