I run Gravely 460's with the 5400 transaxle. I too find them to be extremely smooth and responsive. Additionally, it appears that pump and motor systems are rapidly going the way of the dodo. The Gravely Pro-Master series, their long time premier model, which utilizes a pump and wheel motors system, is now only offered in one deck width with only a single engine option. That is handwriting on the wall, in my book, that it will be phased out in the near future.
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