Simplicity cast iron vs aluminum transmissions

[Del]

I noticed that the new Sovereign, which looks like a heavy duty machine out of the past, has a cast iron transmission. Very good in my book if one is going to do some garden plowing with a mold board plow. I also noticed that the Landlord and the new top of the line Legacy have what appears to be an aluminum cased transmission. Are they as strong as the Sovereign's old style cast iron transmission?

Thanks,
Bill

[Fred]

Bill,
The Sovereign is, indeed, an old design, and that is the problem. Simplicity makes that 130 pound cast-iron trans themselves, and it and the "T"-box are expensive. They would dearly love to replace the Sov with a "Sov II", because of costs and because that trans was not originally designed to take a hydro, but they haven't yet figured out which way to go. The transaxle in the SunStar and Legacy is a Peerless (div. of Tecumseh) 2600 Series, and is actually stronger than the Sov trans and is specifically designed for an in-line shaft-driven hydro. It is a very common trans under many heavy garden tractors and has a good service record. It also is available to the OEM with single- or dual-range, various gear ratios, with or without a differential lock, and optionally with an in-line shaft rear PTO at engine speed or with a gear reduction. If you look closely at the Legacy you'll find that it's the heavy duty version of the 2600, which has cast-iron axle extension housings that carry the load between frame and wheels. I regularly pull a three-point 12" single-bottom Brinly-Hardy with my SunStar, with no problems.
My two cents,
Fred