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The Difference Between GL-4 and GL-5 Gear Oil

Written by Charleen

The Difference Between GL-4 and GL-5 Gear Oil

The main difference between GL-4 and GL-5 gear oils is in the level of extreme-pressure (EP) additives.

It’s really very simple. They are not interchangeable and GL5 didn’t replace GL4.

by Eddie Yorkman,|July 5, 2022

If you’ve ever purchased gear oil, or spent any time looking at gear-oil specifications, you have undoubtedly come across the API GL-4 and GL-5 specifications. You may have wondered, what is the difference between GL-4 and GL-5 gear oil? Where can I buy GL-4 and GL-5 gear oil?

Severity – Hypoid gears vs Helical

The American Petroleum Institute (API) classifies gears using GL ratings, ranging from GL-1 to GL-5. Higher GL rating numbers represent more severe applications; GL-1 is the least severe and can usually be satisfied with a motor oil, while GL-5 is the most severe GL rating.

EP additives

The main difference between GL-4 and GL-5 gear oils is in the level of extreme-pressure (EP) additives. EP additives effectively protect gears by providing a sacrificial layer on gear surfaces; these additives are essential for protecting gears operating under heavy loads and extreme temperatures. A typical GL-5 gear oil provides about twice as much EP additive in its formulation compared to a GL-4 gear oil.

Where are GL-4 and GL-5 gear oils used?

GL-4 gear oils are typically recommended for spur and helical gears found in manual transmissions and transaxles operating under moderate speeds and loads.

GL-5 gear oils are typically recommended for hypoid gears in automotive axles operating under high-speed, high-load conditions.

What type/weight gear oil should I use?

For top protection and performance, it is best to consult your owner’s manual/Shop manual for the manufacturer’s recommendation. There, you will find both the specified viscosity (75W-90, 75W-140, etc.) and specification (API GL-4, API GL-5, API MT-1, etc.) recommended for your application. Almost all hypoid gear sets require GL-5 due to the need for significant extreme-pressure protection.

Note the 2nd number is the KEY weight under operating temperatures and conditions. 990, 110, 140, 250, etc..  For example our 75W-80 covers and overlaps the recommendations where 80W-90, 85W-90 are written.

What’s the best gear oil for my vehicle?

AMSOIL SEVERE GEAR® Synthetic Gear Lube excels in protecting gears and bearings from the rigors of severe-service operation. By design, it resists breakdown from high heat, preventing acids and maintaining a barrier to prevent metal-to-metal contact while conditioning seals. Its wax-free construction also improves cold-flow properties, improving fuel economy and cold-weather performance.

• Superior film strength
• Controls thermal runaway
• Protects against rust and corrosion
• Helps reduce operating temperatures
• Maximum efficiency
• Long oil, seal and equipment life
• Flexible easy-pack for clean, fast installation

SEVERE GEAR is recommended in differentials, manual transmissions and other gear applications requiring an API GL-5 gear oil. It can also be used in axles where an API GL-4 lubricant is recommended.

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No Fear and Loathing at the Mint 400

Written by Charleen

No Fear and Loathing at the Mint 400

Lindsay Premo|

“In some circles, the Mint 400 is a far, far better thing than the Super Bowl, the Kentucky Derby and the Lower Oakland Roller Derby Finals all rolled into one. This race attracts a special breed…”  – Hunter S. Thompson

In 1971, author Hunter S. Thompson wrote his famous article “Fear and Loathing in Las Vegas” while covering the Mint 400 for Sports Illustrated. Thompson’s article was later adapted into a novel and then into a film starring Johnny Depp and Benicio Del Toro, signifying the Mint 400’s relevance to American pop culture.

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The Mint 400 started in 1967 near Las Vegas as a public relations event to promote the Mint Hotel’s annual deer hunt. Race organizers sent two matching dune buggies 600 miles through the desert from the Mint Hotel to the Sahara Hotel in Lake Tahoe, Calif. The event because famous overnight, with national television coverage drawing the attention of race fans across the country.

Some of the “special breeds” who have competed in this event include Al and Bobby Unser; Rick Mears; Mickey Thompson; actors Steve McQueen and Patrick Dempsey; and comedian Jay Leno.

AMSOIL racers to take to the desert

Coming off an impressive seventh-place finish at the King of the Hammers UTV race last month, two-time Mint 400 champion Bryce Menzies is looking to do it again in this year’s Trick Truck class. His fellow #TeamAMSOIL racer Brad Lovell is also looking to keep the momentum going following a second-place finish at last month’s King of the Hammers EMC. Lovell, who took second in the Vintage Open Class at last year’s Mint 400, will be competing in his first ever 6100 race.

Prior to racing on Friday, Lovell’s pit crew will participate in the Method Race Wheels Pit Crew Challenge along Fremont Street on Thursday evening.

Stop by the AMSOIL booth

AMSOIL will be located on Fremont Street throughout all the pre-race events. Be sure to stop by and pick up your exclusive Runs on Freedom™ bandana. Fill out our survey on Friday, March 8 for a chance to win the fender from Lovell’s new 6100 truck following the race.

On Thursday and Friday, Menzies’ UTV from King of the Hammers will be on display. Lovell’s Bronco will be displayed Thursday and his new 6100 on Friday. Both Menzies and Lovell will be in the booth Friday at 2 p.m. local time signing autographs for fans.

Buy two SEVERE GEAR® easy-packs, get one free

We’re also offering a special promotion as part of our Mint 400 partnership. Buy two AMSOIL SEVERE GEAR Synthetic Gear Lube easy-packs and get one free. It’s the same gear lube Menzies and Lovell trust in their race vehicles.

Find more information on the promotion here.

As always, tune into our social media channels for updates throughout the race. The week kicks off Wednesday, March 6 in Las Vegas. Check out the complete schedule of Mint 400 events here.

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Twitter

We’ll see you at the races!

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Announcement – Banks Performance/AMSOIL Partnership

Written by Ches Cain

Known for Being The Pinnacle of Performance, AMSOIL and Banks Make for Logical Partnership

Much more to be published on this in the future of course – here’s just a little about the two firms.

Endorsement To Better Serve Customer Base

Banks Power has recently endorsed AMSOIL as the lubricant of choice. As the premier design and manufacturer of power enhancing products for diesel and gas powered vehicles, Banks Power is well-known and respected in the diesel enthusiast community. Similar to AMSOIL, the company’s fundamental principles combine old fashioned business ethics and service with leading technology. Customers expect elegantly engineered products, superior construction, scientifically proven performance and competitive prices.

amsoil and banks performance partmership

Technological Achievements

Banks company history is studded with technological achievements. Including Gale’s pioneering work in turbocharging marine engines in 1969; the premiere of twin-turbo small block Chevy engines in 1978; the invention and patent of the Banks OttoMind electronic fuel management module in 1997; transmission control systems; and the recent invention and patent of the iDash DataMonster, the only instrument to calculate, log and display an exclusive suite of engine parameters, including manifold air density.

Engineering

First and foremost, Banks is an engineering firm. Established in 1958 Banks has grown to 100+ employees on a 12 acre campus. The mechanical engineering department is staffed with world class automotive experts who design and test the latest high performance equipment. In the Race Shop, special project vehicles feature cutting edge diesel and gasoline development, multiple turbo applications, mind-boggling horsepower and head turning style. Sophisticated electronic engineering technologies are applied to engine improvement in the rapidly growing Computer Systems Engineering Department. Gale Banks Engineering Designs turbocharged engines from the centerline of the crankshaft out.

Amsoil as included differential oil with banks products

“Banks Protected by AMSOIL”

Banks Protected by AMSOIL endorsement will appear on all digital media reaching millions of enthusiasts who have yet to experience the AMSOIL difference.

Creating further valuable exposure, Banks is offering its new differential cover bundled with four Easy Packs of the AMSOIL Severe Gear as the first fill lubricant coupled with a flyer with information on how to buy or find AMSOIL products.

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More AMSOIL Products Available in the Award-Winning Easy-Pack

Written by Charleen

The New EZ Pack is making waves! No more oil change Hassle

Jamie Gibson|

Sometimes an idea so great comes along it makes some wonder, “Why didn’t anyone think of this sooner?”

Case in point: AMSOIL easy-packs. Their innovative, flexible design has revolutionized the challenging task of changing fluids, reducing mess, waste and hassle.

Less Mess. Less Waste. Less Hassle.

After extensive research and testing to produce a concept worthy of the AMSOIL name, the AMSOIL SEVERE GEAR® Synthetic Gear Lube easy-pack launched in August 2018 to resounding success. It has earned rave reviews, a SEMA Global Media Award, a Flexible Packaging Achievement Award and the expectation that other companies will soon attempt to follow the AMSOIL lead once again.

Here’s what one customer says about the SEVERE GEAR easy-pack.

“175,000 trouble-free, heavy-haul miles. The new gear oil pouch makes it so easy to change diff fluid. Make the switch to AMSOIL today. Proven protection in the worst conditions.”

Nate the Hotshot
Laurel, Miss.

Since the launch of the AMSOIL SEVERE GEAR Synthetic Gear Lube easy pack, AMSOIL has expanded its easy pack offerings to include even more products. Check those out below and prepare for a new way of changing fluids with less stress and mess than what you’re used to enduring.

SEVERE GEAR Synthetic Gear Lube

Available in 75W-90, 80W-90, 75W-110 and 75W-140 viscosities, SEVERE GEAR is engineered for high-demand applications found in today’s autos/pick-up trucks, SUVs, heavy equipment and other hard-working vehicles. It delivers extreme-temperature performance no matter where the roads you travel happen to be.

Synthetic ATV/UTV Transmission and Differential Fluid

AMSOIL Synthetic ATV/UTV Transmission and Differential Fluid delivers severe-service protection against wear while riding aggressively or tackling tough terrain around your property. It protects heavily loaded, high-torque gears to promote long equipment life, even in extreme operating temperatures.

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Bonus: AMSOIL synthetic lubricants are Warranty Secure, keeping your factory warranty intact. Click here to learn more about your freedom to choose the lubricants you think best – and to score your free AMSOIL Runs on Freedom decal.

Synthetic Marine Gear Lube

AMSOIL Synthetic Marine Gear Lube is an exclusive AMSOIL formulation of synthetic base oils and high-performance additives that address specific concerns of marine applications. It is fortified with extreme-pressure (EP) additives for superior protection of fast-accelerating, high-torque/horsepower engines. It delivers advanced outboard protection against power loss and gear wear, even with up to 15 percent water contamination.*

*Based upon AMSOIL testing of AMSOIL Synthetic Marine Gear Lube 75W-90 in ASTM 3233 and ASTM D892.

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Signature Series Synthetic Automatic Transmission Fluid

Available in both Fuel-Efficient and Multi-Vehicle formulations, AMSOIL Signature Series ATF provides excellent wear protection and performance in today’s demanding transmission applications. Benefits include protection against thermal breakdown, cold-temperature fluidity, friction durability and maximum fuel economy.

Manual Transmission & Transaxle Gear Lube

AMSOIL Manual Transmission & Transaxle Gear Lube is formulated to meet the demands of towing, heavy hauling and performance driving typically found in manual transmissions. It delivers quick shifts and excellent wear protection in hot rods and muscle cars to promote smooth, fast engagement of synchronizers and gears. Its shear-stable formulation maintains viscosity and protects brass synchronizers while supporting equipment longevity.

Shop AMSOIL Easy Packs

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