So, I'm now working on a 2004 Toro Wheelhorse garden tractor. It has the Peerless MST 5 speed manual shift transmission, which I think has a few issues. It will work perfect in reverse every time, but it only works sporatically in all 5 forward gears. The only exception is in 5th gear, where it works most of the time but it jumps into gear and does a wheelie on pavement. I almost hit the wife's minivan with it once. I pulled the unit out of the tractor and dumped the gear oil inside in hopes that I'd find that there was little to no oil in it, but about half the capacity drained out. I refilled with 16 oz of 80W-90 and there was no improvement. One other thing it does is when shifting through the gears with the clutch/brake depressed it will randomly pop into a gear and buck forward a bit, which from my limited experience with tractors is what happens when the transaxle is shifted out of neutral. If I then quickly select any gear it will propel forward for a little or even more, but that will be really random as to how long it will continue to move. It even chugs forward sometimes, like it's in gear and moving and then pops out for a second and then pops back into gear again. I've checked all the adjustments and belts, and everything is in good working order. This is proven out in the fact that reverse works every time. Anyone that could provide a diagnosis would be appreciated. Thanks.