Sierra Premium Gear Lube GL-5 – 1 Qt
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Sierra Premium Gear Lube GL-5 – 1 Qt
A reliable, correctly specified gear lube for routine lower unit maintenance on outboard and sterndrive engines. Sierra Premium Gear Lube meets GL-5 classification and is a direct replacement for hypoid 90 gear lubricants — the standard spec for most outboard and sterndrive lower units in both freshwater and saltwater service.
The 1-quart size is the right amount for a standard lower unit gear oil change on most single outboard or sterndrive applications, with enough to fill from the bottom drain port to the top fill port without waste.
Key Benefits
- GL-5 rated — meets requirements for general marine lower unit applications
- Direct replacement for hypoid 90 gear lubricants
- Suitable for freshwater and saltwater operating conditions
- Reduces friction and protects gears, bearings, and gear case components
- Compatible with a wide range of outboard and sterndrive lower units
Specifications
- Classification: GL-5
- Replaces: Hypoid 90
- Volume: 1 Quart
- Application: Outboard & Sterndrive lower units
- Environment: Freshwater & Saltwater
Related Products
- Sierra Premium Gear Lube – 10 oz
- Sierra Premium Gear Lube GL-5 – 5 Gallon Pail
- Sierra Hi-Performance Gear Lube – 1 Qt
- Sierra Hi-Performance Gear Lube & Pump Kit – 1 Qt
- Sierra Gear Lube Pump
Parts Desk Insights
This is the standard gear lube for most outboard and sterndrive lower units — if your engine manual calls for GL-5 or hypoid 90, this is the correct product. One quart is typically sufficient for a full lower unit change on a single outboard; larger or twin-engine setups may need two. If you need a pump and adapters to do the job cleanly, the Hi-Performance Gear Lube & Pump Kit includes everything in one box, or pick up the Sierra Gear Lube Pump separately. If your engine manual specifically calls for hi-performance gear lube rather than standard GL-5, see the Sierra Hi-Performance Gear Lube instead. For marinas or multi-boat service, the 5-gallon pail offers better value at volume.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.