Amsoil Authorized Dealers John & Zenaida Cardell

Severe Gear® SAE 250 (SRT)

Amsoil Severe Gear (SAE 250) Gear Lube (SRT)

Product Highlights View Full Description

Recommended for racing applications that require heavier-viscosity gear lubricants. Engineered specifically for the demands of severe racing conditions. Provides improved flow over conventional oils, reducing viscous drag and power loss. The ultimate line of defense against wear, pitting and scoring. Extends gear life.

Racers, rockcrawlers and other off-road enthusiasts invest thousands of dollars and countless hours building and modifying their rigs. Professional competition and off-roading for pleasure take a toll on differential gears and bearings. For maximum differential performance and life, enthusiasts need a gear lube that combines excellent wear protection, superior fluidity and the ability to cling to parts during severe operation. Amsoil Severe Gear EP Synthetic Racing Gear Lubricant delivers peace of mind that expensive, high-performance racing and competition differentials are well protected in the toughest conditions.

Package Sizes (SRT)

SRTQT (SRTQT-EA)1-Quart BottleEach
SRTQT (SRTQT-CA)1-Quart BottleCase of 12
SRT1G (SRT1G-EA)1-GallonEach
SRT1G (SRT1G-CA)1-GallonCase of 4
SRTTP (SRTTP-EA)2.5-GallonEach
SRTTP (SRTTP-CA)2.5-GallonCase of 2
SRT05 (SRT05-EA)5-Gallon PailEach
SRT16 (SRT16-EA)16-Gallon KegEach
SRT30 (SRT30-EA)30-Gallon DrumEach
SRT55 (SRT55-EA)55-Gallon DrumEach
SRT27 (SRT27-EA)275-Gallon ToteEach

Protects Against Wear

Severe Gear is formulated with extra-heavy treatments of additives and shear-stable, heavy synthetic base oils for high film strength. It cushions metal surfaces and absorbs the impact of moving parts while proprietary extreme-pressure additives form an iron-sulfide barrier on gear surfaces for the ultimate line of defense against wear, pitting and scoring.

Provides Fast Startup Protection

Severe Gear doesn’t contain the irregularly sized and shaped molecules inherent to conventional oils. As a result, it provides excellent fluidity despite its high viscosity to quickly reach gears and bearings at startup. Its superior fluidity also reduces viscous drag and energy loss, helping drivers put maximum power to the ground.

Clings Tenaciously to Parts

Severe Gear is specifically engineered for high-horsepower, high-torque conditions where centrifugal gear lube sling-off is encountered. This tenacious formulation clings to gears and bearings for maximum protection during shock loading, high G-forces and where pinion gears are installed at steep angles. Severe Gear provides excellent reliability and helps extend gear life.

  • Resists sling-off from G-forces and high speeds
  • Clings to gears – high-pinion style and at steep angles
  • Promotes cooler operating temperatures
  • Helps extend gear and bearing life

Service Life

Amsoil Severe Gear EP Synthetic Racing Gear Lube is intended for severe racing and other applications where extended drain intervals are not beneficial. Amsoil recommends changing the lubricant as conditions dictate. Where extended drain intervals are desired, Amsoil recommends monitoring by oil analysis.


Amsoil Severe Gear EP Synthetic Racing Gear Lube is compatible with synthetic and conventional automotive gear oils. Mixing Amsoil gear oil with other oils, however, will shorten the oil life expectancy and reduce the performance benefits.

Aftermarket oil additives, other than those specified by Amsoil, are not recommended for use with Amsoil gear oil.


Use in hypoid gear differentials and other applicaitons that require a high-viscosity API GL-5 gear lube, including off-road trucks, rock racers, rock crawlers, pulling tractors, funny cars, dragsters, heavy-duty trucks and equipment where increased lubricant film is necessary. Where limited-slip performance is required, use Amsoil Slip Lock® limited-slip additive.

Amsoil Product Warranty

Amsoil products are backed by a Limited Liability Warranty. For complete information visit

Amsoil Severe Gear (SAE 250) Gear Lube (SRT)
Kinematic Viscosity @ 100˚C, cSt (ASTM D445)47.0
Kinematic Viscosity @ 40˚C, cSt (ASTM D445)494.5
Viscosity Index (ASTM D2270)151
Pour Point ˚C (˚F) (ASTM D97)-24 (-11)
Flash Point ˚C (˚F) (ASTM D92)210 (410)
Brookfield Viscosity @ -40˚C, cP (ASTM D2983)102,100
Foam Stability (ASTM D892)0/0, 20/0, 0/0
Copper Corrosion 3 hr, 121˚C (ASTM D130)1B
Falex Procedure B (ASTM D3233) (failure load, lbf.)3500
Four-Ball Wear Test (ASTM D4172 @40kg, 75°, 1200 rpm, 1hr), Scar, mm)0.43

*All trademarked names and images are the property of their respective owners and may be registered marks in some countries. No affiliation or endorsement claim, express or implied, is made by their use. All products advertised here are developed by Amsoil for use in the applications shown.

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