I don't think it will matter but I will say this. Hytran is great if you can drain the fluid and scrape out all the crap that gels up on the bottom. You can't do that on your GT2554 like you can the old stuff. There is no rear cover to remove. Look at the Deere stuff, they don't want all the moisture coagulating on the bottom because their differentials are like the newer Cub stuff, they gotta be split to be cleaned. +1 on the synthetic 15-40. I think I will be switching over to that on all my stuff for now on.
What paint scheme are you going to do on this one " 2016 Stanley Cup Champs"
