Been chewing (heavy pitting) up lower Bravo gears, 15/19T (XR, Sportmasters) pinions more than driven gears, on a regular basis and from my experience, there are good sets that last a while before magnets are looking like Chia Pets. Best life to date is 120 hrs., have also chewed them up in as little as 9 hrs. Set up is by the book, shooting for the tighter side, but life is still pretty short.

I'm in the process of building up another spare drive and recently purchased a set of new gears off ebay, What I thought I was buying were Merc gears but what I received was a brand new set of aftermarket gears. I'm more than a bit reluctant to install them and risk destroying a Sportmaster case if they fail...

I'm looking for first hand experience with these aftermarket gears in performance boat applications and what were the results.

Has anyone had a set of these gears tested for hardness? How do they compare to Mercury? The set I received do appear to be well made but I'm no metals expert..

Thanks in advance,

Kurt

Running a 2nd year on a SEI lower behind warmed up 500s and a 43 BT. No issues. Lower was at my house in 48 hours after buying thru Diamond Performance. Fluid changes have yielded no issues as well.

Thanks for the input. That BT is a good test for it!

I have used both, no problems with either brand.

I remember reading a post that the SEI gears actually were tested and were slightly harder than Merc gears.

Thanks Griff, I just found an old post from Warren that mentioned hardness several points greater than Merc. I
m going to install them in my spare drive. Hopefully, it will be a while before testing will be done!