Banks Diff Cover...
Fleet Owner
Joined: Aug 2010
Posts: 21,253
Likes: 1,656
From: Reynoldsburg, Ohio
Otherwise you posted a nice reply so thanks for joining FTE even if for a short stay!
Logistics Pro
Joined: Nov 2002
Posts: 4,788
Likes: 20
From: Mansfield, TX USA
Dude. I created an account just to reply to this comment.
If you watch the video instead of concern trolling,
* * *
The factory unit doesn’t do this friction/work on the oil because of its rounded shape. All he did was improve upon the FACTORY design and made it better by adding oiling channels to help give it a more direct path to carrier bearings (all proven with testing using clear acrylic mock covers). The bottom has ram air induction that curves up to the fins and keeps temps down. It’s got a sight hole for fluid level. It’s a machined surface with an o-ring. It’s thorough engineering.
If you watch the video instead of concern trolling,
* * *
The factory unit doesn’t do this friction/work on the oil because of its rounded shape. All he did was improve upon the FACTORY design and made it better by adding oiling channels to help give it a more direct path to carrier bearings (all proven with testing using clear acrylic mock covers). The bottom has ram air induction that curves up to the fins and keeps temps down. It’s got a sight hole for fluid level. It’s a machined surface with an o-ring. It’s thorough engineering.
And yes, I did watch the video and if you read all of my posts on this subject, you would have seen my discussion regarding the payback period for this wildly expense diff cover versus Gale Banks's optimistic fuel economy predictions.
Give Gale Banks his due diligence and watch his video before making ignorant comments. Most manufacturers in the aftermarket aren’t transparent like this and we should appreciate the ones who are like Banks. They couldn’t hold a candle to his name because they sell crap and they know it.
Humans, particularly those in the USA, seem to see things as "good, better, best". Never mind that the "good" product will last two lifetimes, give me the "best". The entire advertising industry is build around this unique human behavior.
Logistics Pro
Joined: Nov 2002
Posts: 4,788
Likes: 20
From: Mansfield, TX USA
Snake oil is a euphemism for deceptive marketing. It refers to the petroleum-based mineral oil or "snake oil" that used to be sold as a cure-all elixir for many kinds of physiological problems. Many 19th-century United States and 18th-century European entrepreneurs advertised and sold mineral oil (often mixed with various active and inactive household herbs, spices, and compounds, but containing no snake-derived substances whatsoever) as "snake oil liniment", making frivolous claims about its efficacy as a panacea. William Rockefeller Sr. sold "rock oil" as a cancer cure without the reference to snakes. Patent medicines that claimed to be a panacea were extremely common from the 18th century until the 20th, particularly among vendors masking addictive drugs such as cocaine, amphetamine, alcohol and opium-based concoctions or elixirs, to be sold at medicine shows as medication or products promoting health.
So yes, when I see some super duper product, guaranteed to do this or that, I am a cynic. And not always because it does not work. Many, many times it is because it just isn't necessary.
Please read my many posts on "good, better, best".
Fleet Owner
Joined: Aug 2010
Posts: 21,253
Likes: 1,656
From: Reynoldsburg, Ohio
Fewer products have earned the right to be called snake oil than those sold in the automotive industry. Just look at an old JC Whitney catalog if you do not understand what I mean.
So yes, when I see some super duper product, guaranteed to do this or that, I am a cynic. And not always because it does not work. Many, many times it is because it just isn't necessary.
Please read my many posts on "good, better, best".
So yes, when I see some super duper product, guaranteed to do this or that, I am a cynic. And not always because it does not work. Many, many times it is because it just isn't necessary.
Please read my many posts on "good, better, best".
(Reps sent BTW 
)Me too---if it looks good it just has to be better right?
Logistics Pro
Joined: Nov 2002
Posts: 4,788
Likes: 20
From: Mansfield, TX USA
Here are some test results from the Banks website:
At the top of the 550 second hill climb, running the 3.9 quart stock differential cover, the lubricant temp was 205°. Filled with 7.5 quarts, the Mag-Hytec recorded 199° while the Banks filled with 4 quarts recorded 192.5°. Even with less lubricant, the Ram-Air cover controlled heat 2X better than the flat-back during the high horsepower hill climb!
From the crest to the end of the test, running 55 mph for 700 second at relatively constant elevation, the stock cover cooled from 205° to 195°. The Mag-Hytec cooled to 192.5° and 178.5° for Banks, a 5X improvement over the Mag-Hytec and by extension all other flat-back copies.
and
Testing was started after a 100° nominal temperature was achieved. Using a 2007 Dodge Ram 6.7L 3500 dually, the truck was brought 60 mph and loaded to 200 hp, typical of pulling a heavily loaded trailer up a 6% grade. Lubrication was changed between every test.
The equivalent of 60 MPH road speed air was directed under the truck’s belly using the Banks Wind Machine, aided by additional shop fans. Air damns were constructed to contain the airflow under the truck toward the rear differential.
At the end of the 60 minutes test, the lubrication temp was 289°, AFE was 261° or 28° cooler than stock. Banks was 228° or 61° less than stock. Banks outcooled AFE by 118% and by extension, all flatback covers.
I have no doubt that these numbers are all accurate the the tests were unbiased.
But so what?
These were both extreme tests under conditions not likely to be met by the majority of people very often, if ever. So very few will benefit from the more effective cooling.
But even for those that might operated under these conditions, there is nothing to indicate that even at 289*, there is any degradation of the lubricant, especially now with the factory fills being synthetic.
So yeah, Banks cools better. But the stock covers apparently cool just fine.
FYI - The specifications for the factory fill include a flashpoint of 410*F and a viscosity of 11.53 cSt at 100*C.
Here is Ford's description of the factory fill:
The Banks or any other special cover is simply a solution to a problem that does not exist.
It's called MARKETING.
Now the cool factor? I have no answer to that.
Road Test: Heat Rejection — Grapevine Trailer Test
Road tests were performed on a stretch of California’s infamous Grapevine (Interstate 5) on the same truck, with the same driver and the same load, at the same time of day and at same temperature. Starting with a nominal 78° ambient temperature, the operator pulled an 11,650 lb weight trailer with a 2018 Chevy Silverado 2500HD 6.6L diesel. Gross combined weight was 19,750 lbs. The rear differential was heated by maintaining a constant speed of 55 mph up a 6% grade for 5 miles, ascending over 1,600’.At the top of the 550 second hill climb, running the 3.9 quart stock differential cover, the lubricant temp was 205°. Filled with 7.5 quarts, the Mag-Hytec recorded 199° while the Banks filled with 4 quarts recorded 192.5°. Even with less lubricant, the Ram-Air cover controlled heat 2X better than the flat-back during the high horsepower hill climb!
From the crest to the end of the test, running 55 mph for 700 second at relatively constant elevation, the stock cover cooled from 205° to 195°. The Mag-Hytec cooled to 192.5° and 178.5° for Banks, a 5X improvement over the Mag-Hytec and by extension all other flat-back copies.
Chassis Dyno Testing: Heat Rejection — Sustained Power Test
This test was used to determine high load, steady state thermal management. Gale had originally requested a 90 minute, 250 hp test. Gale soon regretted that request. At 90 minutes the lubrication measured 316° and was still climbing. The intense test even resulted in the dyno catching on fire. After repairs were made, the test was revised to 60 minutes at 200 hp.Testing was started after a 100° nominal temperature was achieved. Using a 2007 Dodge Ram 6.7L 3500 dually, the truck was brought 60 mph and loaded to 200 hp, typical of pulling a heavily loaded trailer up a 6% grade. Lubrication was changed between every test.
The equivalent of 60 MPH road speed air was directed under the truck’s belly using the Banks Wind Machine, aided by additional shop fans. Air damns were constructed to contain the airflow under the truck toward the rear differential.
At the end of the 60 minutes test, the lubrication temp was 289°, AFE was 261° or 28° cooler than stock. Banks was 228° or 61° less than stock. Banks outcooled AFE by 118% and by extension, all flatback covers.
But so what?
These were both extreme tests under conditions not likely to be met by the majority of people very often, if ever. So very few will benefit from the more effective cooling.
But even for those that might operated under these conditions, there is nothing to indicate that even at 289*, there is any degradation of the lubricant, especially now with the factory fills being synthetic.
So yeah, Banks cools better. But the stock covers apparently cool just fine.
FYI - The specifications for the factory fill include a flashpoint of 410*F and a viscosity of 11.53 cSt at 100*C.
Here is Ford's description of the factory fill:
Motorcraft® SAE 75W-85 Premium Synthetic Hypoid Gear Lubricant is manufactured using high-quality synthetic oils and performance additives to provide improved high-temperature thermal and oxidative stability. This product has been formulated to improve fuel economy and helps to reduce operating temperatures. It has enhanced wear protection for hypoid gears, excellent shear stability and protects from rust and corrosion
It's called MARKETING.
Now the cool factor? I have no answer to that.
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Logistics Pro
Joined: Nov 2002
Posts: 4,788
Likes: 20
From: Mansfield, TX USA
But under normal driving conditions, fluid change is not required, and required only every 150,000 miles if using full syn gear oil.
Axle and Transfer Case Maintenance Axle(s) and transfer case, 4X4 only, fluid changes or level checks are not required unless a leak is suspected or the assembly has been submerged in water. During long periods of trailer towing with outside temperatures above 70°F (21°C) or at wide-open throttle for long periods above 45 mph (72 km/h), change the rear axle fluid every 30,000 mi (48,000 km) if the rear axle is filled with non-synthetic fluid. This interval can be waived and the 150,000 mi (240,000 km) service interval can continue if the rear axle is filled with 75W140 synthetic gear fluid meeting Ford specification WSL-M2C192-A, part numberXY-75W140-QL, or equivalent. Add friction modifier XL-3 (EST-M2C118-A) or equivalent for complete refill of Traction-Lok rear axles.
So if you tow, every 30k miles and (I think) every 50k miles if you do not tow. But Dana rear axles only.
Ford-made Sterling axles do not require any fluid changes. Might be a good idea to change the fluid at some point, but something that certainly is not going to be routine.
Fleet Owner
Joined: Aug 2010
Posts: 21,253
Likes: 1,656
From: Reynoldsburg, Ohio
Nice part if I say so myself!
Moderator
Joined: Jan 2004
Posts: 13,851
Likes: 111
From: SW Va
On the Yukon cover photo, I see what looks like a potential sealing problem on at least 3 of the casting mounting bolt holes, two at the top & one at the bottom left & maybe two more, that are off center in the cover mounting flange. Don't think I'd want to try sealing that puppy, as it looks like a real potential for leaks around those off center cover through bolt holes. Another flat back cover with unknown internal fluid dynamics????
Fleet Owner
Joined: Aug 2010
Posts: 21,253
Likes: 1,656
From: Reynoldsburg, Ohio
On the Yukon cover photo, I see what looks like a potential sealing problem on at least 3 of the casting mounting bolt holes, two at the top & one at the bottom left & maybe two more, that are off center in the cover mounting flange. Don't think I'd want to try sealing that puppy, as it looks like a real potential for leaks around those off center cover through bolt holes.
Naturally I won't know if your concern comes to be PawPaw but it is something I'll watch. I do intended to use RTV or some sort of sealant on the housing or cover during installation. With the drain provision I don't anticipate have to remove the cover again. Fingers crossed..........
Here's one additional image showing this cover from the side---seems to closely follow the stock factory cover:
Thanks for the observations y'all---good things to consider!