SQ600 -Can I run heavier blades?

[RickB]

7555BH means nothing to me except it was referred to as uplift. That doesnt speak to a mass comparison. However, the blade bar you quoted sounds adequate for the 33% heavier blade the op introduced.
larry

36BH blades are 1/2" x 3"x24-3/4" flat.
7555BH blades are 1/2"x4"x24-3/4" with a wing crimped on about 6" of the end.
7555BH is both a heavier duty blade than the 36BH and is an uplift blade. Standard equipment on 5 foot cutters heavier duty than Squealers, and standard equipment on the RH deck of most Bush Hog 15 foot batwing mowers. I sell them as replacement blades for 60" squealers unless the purchaser specifies the lighter, cheaper 36BH blades. They give a better cut quality, and longer service life.

There is also a 462 blade that is 3-1/2" wide and flat with no wing.

 

[SanDucerro]

The parts manual for the SQ600 shows both the 36BH and the 7555BH blades. The exploded view drawing has them listed together under the same number reference with the 7555BH having the following description: Blade 5' - Uplift (Optional). The only other items on the exploded view drawing with more than one option are the gearbox (4 different colors available), and the deck decals (here again - 4 different colors available and a "French" option as well). All other items are the same, so one would have to assume there is no difference between the SQ600 with or without the uplift option other than the blades themselves.