SGT's are bad about loose or broken bolts in the rear assembly. Make sure all your bolts holding the rear are torqued to 30ftlbs and no more. Also check and make sure that the front tabs on the transmission aren't broken. This will cause the transmission assembly to flex and crack your hydro lines and all kinds of other problems. I highly recommend that you install a set of rear braces if your machine doesn't already have those.
Broken front tab
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Here are the rear braces needed for a SGT.
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