This summer got into a new but used boat (2006 model year with low hours) and already one blown drive. Engines are 496 HO's. I am just curious if the size of the boat is pushing the limits, and if i should investigate other options if this happens again.

What broke on the drive? If it is an upper, then you might want to look into an Imco SCX, it will adapt to the B3 lower and give you a lot better service. How heavy is your boat?

Yes, the upper gave way and will probably be replaced with a new one very shortly. The upper teeth began to sheer and then the metal pieces jammed in the bearing. I shut it down immediately. The lower is fine except one bearing, so that will be rebuilt. The boat is still under Formula Guard warranty until next June, so I am lucky. The boat is 16,000 lbs, but then you add for the 250 gallons of fuel, 100 gallons of water, gear, etc., and you're probably over 18,000.

So far, it sounds like this is unusual, but when they go, it is usually the upper that fails...

400 SS's are drive eaters. Merc developed the Bravo III XR and the 4 blade/3 blade prop sets with the 400 SS in mind.

basiclly to much weight for the drives, need to be really easy putting it on plane...

Could the upper just be replaced with a xr upper and keep the dual prop lower? Always thought the bravo 3 lower was more robust since the power/torque is transmitted through two gears rather than one.

Oops, just noticed it is a bravo 3 xr....nebbermind.

The boat has Bravo 3 X drives at this time, not the 3 XR. So these are good discusions. I've already been in contact with the Wisconsin Formula dealer, a place which has been known for performance and "can do," and they are investigating my options, though they really have not said the X drive is not good enough. I am not in a position to spend just for the cool factor of high tech, so an upgrade or some sort has to be logical. I wonder why if the X drives are truly not robust enough, why doesn't Formula fit all 400's with XR drives?

I just did some investigation and it sounds like the Bravo 3 X and Bravo 3 XR packages use the same uppers. So if a guy wants to a more robust upper, upgrading from 3X to 3 XR may not make sense. Seems I had incorrectly assumed a 3 XR would have more durable upper.

Mercruiser could have made a real kick butt bravo had they continued with the dual load path from the props up to the two upper gears and delete the shift mechanism. Then a small transmission on the inside...done! Then maybe add some heat sinks to the housing to get the temps down.