I do not own one, but service Cub GTs on occasion. (most by me buy the LT's) The obvious advantage is the shaft drive if needed. The basic 54" deck is not a slouch. There is very little structural deck issues on even the LT's. Different spindles are offered. Some are loaded w/ a timkin style bearing and some ball bearings. I've serviced enough of the ball bearing spindles, few housings break. The Timkin style bearing spindles get pricey if trauma happens to them. I've seen a couple of the beaten up ones that have had the rear striping rollers ripped out of the basic deck, but that's about it.

well, lessee how this looks: "30.8. Slip the crankshaft pulley down far enough to get the belt off of the pulley, and remove the belt from the crankshaft. See Figure 30.8. NOTE: Belt keepers that are part of the tractor frame prevent the belt from being removed without lowering the pulley. NOTE: The pulley may be removed from the crankshaft at the discretion of the technician." That's right out of the 1000-1500 series serv manual.... and I don't really know if there is enuff room to lift thet engine straight up with the ground drive pulley in place to be able to wangle the ground drive belt off past those fixed keepers - which I fully agree are something of a PITA. just saying... MHO.

The left tension pulley on my LT 1045 Cub Cadet was about 1/2 inch to low and at an angle that took it out of a horizonal plane with the ajacent pullys. Took deck off and removed the bracket that holds both tension pullys. Put the defective pulley in a metal vise and hammered it so that its angle when reinstalled was parralell to the ajacent pullys. This solved the problem. I called Cub Cadet and spoke with the technical representative and he told me that the bracket I had to bend was bent out of shape because I, as many people do, engaged the electric pto to the blades while the deck was in level 3 to mow. He told me to put the deck in its highest position before engaging the pto to engage the blades. This alleviates the stress on the Kevlar belt that is trying to come up to 3600 rpm while in the grass before they start to rotate. This can eventually bend the bracket that holds the tension pulleys. He said he is trying to tell the company to include this in the owners manual.

Can you confirm that the battery is fully charged? Sometimes when key switches go south there can be some circuits left energized and completely discharge the battery by the next time you try. Even though the engine shut off last time you parked it does not prove there were not some circuits left "live". It only proves the "kill" portion of the switch was working. Did you replace the switch with a "genuine and identical" switch? By that I mean "is this the MTD switch listed as the correct OEM replacement switch? Switches may "look alike" on the outside but inside the switch, the rotary contact disc might be configured to make a circuit to a different external connector lug. If that is the case then the wrong wires get energized and it will not work. Make sure you have a good battery first.