After some high speed runs with Mercury High Performance gear oil, the lower unit was flushed and filled with ProGear 21 Type 1.

For testing, we were provided with Alisyn ProGear 21 Type 1 lightweight high performance gear lubricant and ProPower 21 full synthetic two-stoke engine oil. Of particular interest in this evaluation is Alisyn’s super low viscosity, less than zero-weight ProGear 21 Type 1 lower unit gear oil. That’s right – less than zero weight – when all other gear oils carry a viscosity rating between 80-90W.  Alisyn claims increased engine RPM due to a reduction in parasitic drag losses from using this low viscosity gear oil, in addition to providing the best protection available during extreme running conditions. Sound too good to be true? We’ll find out by putting Alisyn ProGear 21 Type 1 to the test in demanding, high performance conditions. Read on…

For testing platforms, we used our finely tuned STV/Mercury 2.5 EFI and requisitioned Herb Terry's very fast Intimidator 21 powered by a Mercury 300X. By testing with 2.5 and 3-litre versions of Mercury’s popular high performance SportMaster gearcases, we could get a fair picture of any RPM or horsepower gains relative to boat weight and setup, as well as oil integrity under intense, yet different operating conditions. Running the gearcase in a surfacing application (such as this test) places maximum loads on the bearing carrier components, especially at 120+ MPH speeds over extended distances.

Testing ProGear's integrity under varying loads included long, high-speed, high-RPM runs in addition to a variety of demanding maneuvers.

Before any testing, we went to Ocean Marine in Freeport, NY, where head mechanic Jim Molnar disassembled and inspected the internal components of our Mercury 2.5-litre gearcase to confirm that they were in perfect working order. Photos were taken to document the condition of the low-hour components, and then the gearcase was resealed and filled with Mercury High Performance lower unit lube.

For our first series of runs, we used Mercury’s High Performance gear oil and achieved consistent top speed runs of 122.2 MPH and 106.0 MPH from the 2.5 and 3-litre-powered boats respectively.  For accuracy, we performed multiple top-speed, long distance runs.  After these runs, the boats were returned to the trailer and we removed the Mercury 90-weight gear oil.  The gearcases were flushed the of any remaining Mercury High Performance oil prior to filling with Alisyn ProGear 21.  Throughout our exhaustive testing, we ran both engines on ProPower 21 two-stroke lubricant mixed at a 32:1 ratio for the 2.5, and through the 300X's oil injection system.

Page Three: Test Results