FREE SHIPPING
Free shipping on every order — no minimum purchase required.DESCRIPTION
Mercruiser Upper Unit Gear Case 1.65R for 1970-1977 Models (165 HP) — Direct replacement for original equipment on classic Mercruiser inboards rated at 165 HP.
- Gear ratio: 1.65R (reverse reduction)
- OEM part number: 5523A18
- Fits 1970–1977 Mercruiser inboard engines
- Complete upper unit assembly ready to install
This original-spec gear case ensures proper propeller speed and thrust characteristics for your vintage Mercruiser — critical for reliable performance and fuel efficiency on the water.
SHIPPING & RETURNS
SHIPPING
- Free Shipping on all orders — no minimum purchase required.
- Orders are dispatched within 24 hours of purchase (business days).
- Estimated delivery: 2–5 business days within the contiguous United States.
- Tracking information emailed as soon as your order ships.
RETURNS
- Exchanges accepted — we want you to be completely satisfied.
- If a part does not fit or is not as described, contact us within 7 days for an exchange.
- Items must be in original, unused condition and in original packaging.
WARRANTY
- 1-Year extended warranty available at additional cost — ask us for details.
FITMENT & COMPATIBILITY
Please verify that this part is compatible with your vehicle's year, make, model, and trim level before ordering. Part numbers and fitment details are listed in the product description. If you have any questions about compatibility, our team is happy to help — contact us by phone or email before purchasing.
Phone: (803) 723-7074
Email: sales@findmypart.shop
Hours: Mon–Fri, 9am–5pm EST
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