Red Line 50304 MT-90 75W-90 GL-4 Manual Transmission and Transaxle Lubricant (MTL) - 1 Quart (4 Pack)
Description
About this item
- HIGH PERFORMANCE - gear protection and longer synchro life. Recommended for GL-1, GL-3, and GL-4 applications.
- QUICKER SHIFTS - perfect synchronizer coefficient of friction and eliminates notchy shifting, even when cold
- REQUIREMENTS - gear oil viscosity of 75W; 80W; SAE 40 10W40 and 15W40 motor oil
- POPULAR GEAR OIL FOR - GL-1, GL-3 and GL-4 applications, as well as where most special synchromesh fluids are specified. Safe for brass synchros, as it lacks the reactive sulfurs found in most GL-5 oils that cause damage
- WHY RED LINE - Established in 1979, Red Line Products perform & protect better than any on the market. No compromises
Guides & Resources
Important Tips
Always confirm your vehicle’s required fluid specifications before use. Ensure proper fill levels and change intervals to maintain smooth shifting and long transmission life.
Product Features
GL-4 Synchro-Safe Formula
Designed for GL-1, GL-3, and GL-4 applications, this high-performance lubricant is safe for brass synchros and supports reliable operation across a wide range of manual transmissions.
Smooth Shifting Performance
Engineered with an optimized friction balance, this lubricant helps deliver smoother, faster shifts and reduces notchy gear engagement, even in cold temperatures.
Advanced Gear Protection
Formulated to provide excellent protection for gears and synchronizers, helping extend component life and reduce wear under demanding conditions.
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Customer Reviews
Based on 6 reviews
Smoother shifting right away
After switching to this fluid, gear changes feel much smoother. It really improved the overall driving experience.
Great for manual transmissions
Works perfectly in my manual car and reduced the rough feel when shifting. Feels more precise and consistent.
Solid performance in all temps
Shifts are smooth even during cold starts. The fluid feels slightly thicker at first, but performance is excellent once warmed up.
Improved gear engagement
Noticed better engagement between gears and less resistance. It’s been very reliable over time.
High quality transmission fluid
You can tell this is a premium product. Keeps everything running smoothly without any grinding.
Great protection overall
Helps protect the transmission and reduces wear. Pouring is a bit slower due to the viscosity, but overall very effective.
