Red Line 75W85 (75W-85) GL-5 Fully Synthetic Gear Oil Ester-Based Hypoid Differential/Final Drive/Transfer Case Fluid LSD Safe with Friction Modifiers BMW G1/G2/G3, Ford WSS-M2C942-A, MB 235.74, Toyota 08885-02506 Part 50109

Premium 75W-85 GL-5 Synthetic Axle and Drivetrain Lubricant for Hypoid Final Drives and Transfer Boxes

Unlock smoother, quieter, longer lasting driveline performance with Red Line 75W-85 GL-5. This ester-rich synthetic axle fluid is engineered for hypoid gear sets, rear axles, final drives and transfer boxes, delivering outstanding film strength and thermal stability for road use, towing, fast-road builds and track days. Formerly known as LightWeight Gear Oil, it is limited slip friendly thanks to built-in friction modifier, so most clutch-type LSDs do not require a separate additive.

Part number: 50109

Why enthusiasts choose it

• Ester-based synthetic formula for exceptional boundary protection under extreme pressure
• Low friction chemistry helps reduce diff whine and chatter, improves driveline smoothness
• High viscosity index for consistent protection from cold starts to heavy-load heat
• Excellent oxidation control for extended drain intervals and reduced wear
• Built-in limited slip friction modifier for most clutch-pack LSD units
• Shear-stable viscosity that holds grade in hard use and racing environments
• Exceeds API GL-5 and meets demanding hypoid gear requirements
• Covers multiple viscosity needs including 75W80, 75W, 80W and 85W, plus applications that call for SAE 30 or SAE 10W30 engine oil as a gear lubricant

Where it works best

• Rear axle oil for performance cars and 4x4s
• Final drive lubricant for fast-road and motorsport builds
• Transfer case fluid where a GL-5 75W-85 is specified
• Racing transaxles commonly using this grade, including various Hewland applications

Important fit note: this product is generally not suitable for most synchromesh manual gearboxes or transaxles that require friction for synchronisers. Always confirm the specification in your owner handbook.

Standards and technical approvals

• API GL-5
• MT-1
• MIL-L-2105E
• SAE J2360

OEM references and popular cross-overs

Frequently chosen where the following specifications or part numbers are called up. Always verify the exact requirement for your vehicle:

• BMW and Mini: 83 12 0 445 838, 83 22 2 295 532, 83 22 2 413 511, 83 22 2 413 512, Castrol BOT 448, Hypoid Axle Oil G1, G2, G3
• Chrysler, Dodge, Jeep: 05136035AA, 68083381AA
• Ford: WSS-M2C942-A, XY-75W85-QL
• GM: 88862826, 92184900, SAF Carbon Mod
• Honda and Acura: 08200-9014A, Hypoid Gear Oil HGO-1
• Mazda: K020-01-SG1
• Mercedes-Benz: MB 235.15, MB 235.7, MB 235.74, A 001989 59 03, A 0012 989 33 03
• Nissan and Infiniti: KDL38-75801P
• Toyota and Lexus: 08885-02506, 08885-02606, 08885-81060, Gear Oil LT and LX
• VW and Audi: G 052 513
• Volvo: G 052 513

Proven by our team and customers

At MJ Modifications we run this gear lube in our own builds and customer vehicles. Feedback on durability, reduced noise and overall driveline feel has been consistently excellent, especially in tuned road cars and track-prepped differentials.

Fitting and service

Want it supplied and installed with the correct fill procedure and torque specs? Book your differential or transfer box service with MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk.

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