The All-New Patented Banks Ram-Air Differential Cover Wipes out the Competition! When it comes to product development, we only make products that increase performance and beat the competition. So when we tested the popular Diff Covers on the market, we were shocked to find out that they actually hurt performance.

This lead to the development of something so New and Incredible that our performance design has a United States Patent. Look, when we set out to build a product for your vehicle, we only engineer the best. What else would you expect from a company with a winning legacy that spans decades. We are here to win, and we just did (Again) in a huge way.

US Patent 10,443,705

18 months of Extensive Testing, What began with a simple question, resulted in millions of video views, innovation and another patented Banks product.

More than a year ago Gale questioned the benefits of aftermarket diff covers asking, Are they just bling or are they really doing something? The answer wasn't as easy to uncover as he'd hoped. Out of dozens of manufacturers, only one claimed to reduce fluid temps, yet no data could be found to back up those numbers. All other manufacturers, and there are many, simply copied the originator's design. Manufacturers still parrot the same phrase today, More oil means cooler temps.

Although there's some truth to it, what Gale and the Banks Engineering Team uncovered were two underlying problems with aftermarket covers; poor air flow and flawed fluid dynamics. The Banks Ram-Air differential cover solves both issues.

After testing covers with flat-backs and those with larger fluid capacities, it was apparent that these covers do not cool as well as advertised and suffer from poor fluid dynamics. As a result, they reduce fuel economy. With its computer-aided and road-tested design, the Banks Ram-Air differential cover retains fuel economy and extends lubrication life!

Many have asked, Why did testing take so long? Well, there was no precedent for testing rear differential covers, nor was any data available for rear differential lubricants as tested in vehicles. There are just too many variables, said the lubricant companies. Creating the proper test procedures was incredibly time-consuming. We started from scratch several times. We even burned up our chassis dyno and destroyed several sets of tires. It was a humbling process.

In all studies, the stock stamped steel AAM (American Axle Manufacturing) was used as a baseline. Competitive covers tested included Mag-Hytec, AFE, ATS, BD, PPE and others, with Mag-Hytec and AFE representing the 'flat-back design category.

Anemometer: Air Velocity
After affixing anemometers fore and aft of the rear differential, a dead zone was discovered. Like the wing of plane, the rear differential splits the air. At a road speed of 70 mph, air speed was measured at 32 MPH in front of the differential and 11 MPH 20 behind the differential. This indicated an area of dead air.

This low velocity dead zone extends as far out as 36 from the back face of the cover. No matter how deep the cooling fins are, they're unable to adequately reject heat due to inadequate airflow over the surface of the fins.

This discovery resulted in the Ram-Air scoop concept. As the truck moves through the air, cool static air is forced into the Ram-Air scoops and directed 90 degree up and through the long? thin heat radiation fins.

Features and Benefits

• Banks cools 5X better than flat-back covers in on-road towing tests over the same road, same weather, operator and vehicle
• Banks cools 118 percent better than flat-back covers in controlled 200hp 60mph sustained dyno tests
• New patented design features Ram-Air scoops
• Forces air up and into massive heat radiation fins providing the fastest cooling on the market
• Provides cold high velocity air, overcoming dead air zone behind differential
• Engineered to break-away if snagged on an obstacle
• Internal heat absorption fins transfer heat through the cover to the external fins
• Dry-mount high-pressure silicone O-ring seal. No messy RTV clean up when servicing differential
• Clears spare tire heat shield, Panhard bars and other suspension components
• Lowest point is the rear differential housing, not the Banks Ram-Air cover
• Limited Lifetime Warranty

Fluid Dynamics

• Cover mates perfectly with differential housing for unobstructed fluid flow
• Ring gear raceway controls the fluid flow path to the pinion and bearing sets
• Axle tube lubricant guides direct fluid to axle bearings without over-filling
• Low fluid aeration means long? r fluid life

Oil service

• No need to remove cover to change fluid
• Magnetic drain plug
• Magnetic fill port plug
• 20 degree angled fill port for easy access
• 1/2 sight glass with contrast screen (visual aid) and Viton seal
• Banks recommends Amsoil 75W-90 Severe Gear Synthetic Gear Lube Easy Pack
• Fill level depends on model year. See vehicle owner's manual
• Technical Specs

Finish: Satin black textured powder coat
Material: A380 aluminum diecast with CNC machined surfaces
Weight: 11.7 lbs
Dimensions: 13.3 X 12.8 X 3.5
Internal volume: Varies
External heat radiation fin count: 23
Internal heat absorption fin count: 22
External heat radiation fin surface area: 694.2 in2
Internal heat absorption fin surface area: 103.1 in2
External heat radiation total surface area: 741.9 in2
Internal heat absorption total surface area: 222.2 in2
Fasteners: 12 x stainless steel 5/16 flange hex bolts