Description
New Aftermarket MerCruiser Gen 2 Lower Unit – Counter Rotation (1991–2020)
This brand-new MerCruiser Gen 2 Counter Rotation Lower Unit is a high-performance, aftermarket gearcase designed for Gen 2 I/O models from 1991 to 2020, with engines rated up to 300 HP. It is specifically built for counter rotation applications only, making it a vital choice for dual-engine boats requiring opposite rotation on one side. This unit will not fit standard rotation setups and is not compatible with 2.00 or 2.40 ratio drives.
Designed for long-term use and precision performance, it comes in a marine-grade black finish and is built from non-OEM parts, offering a reliable and cost-effective replacement. It supports the latest OE#860382 speedometer fitting (not included), which is required for accurate speedometer function.
If you’re unsure about the MerCruiser Alpha One Gen 1 vs Gen 2 difference, this unit is strictly for Gen 2 models and will not fit older Gen 1 lower units. Ensure your compatibility based on serial number and drive specs before purchase.
Pricing
Total Price: $1,295
Less $200 Core Rebate Final Price: $1,095
Product Finish:
- Heavy-duty aftermarket gearcase
- Black marine finish
- Designed for Gen 2 I/O counter rotation systems
Core Rebate Information
- Return your old core, get up to $200 back
- Rebate amount will vary based on the condition of your core
- ♻️ Recycle your core- keep boat parts out of the landfill
Useful Resources
- 🔍 How to find your Boat Engine serial number?
- Still deciding? Watch our YouTube video How to avoid common lower unit replacement mistakes
- To help extend the life of your gearcase, check out our Boat Maintenance Checklist






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