The Grands are a premium tractor & the 00 or 01's are economy tractors.
An equivilant grand will weigh a lot more (30% more maybe) than an economy
The grand has the autoatic shifting GST transmission or the 2 speed shift on the fly HST+ infront of the 3 speed manual transission, so generally nicer transmissions
You can get a factory cab on a Grand, not an option on the economy
Some or all of the economy Ls use the clutch & a lever to engage the PTO, the Grands have a button/knob electrohydraulic engagment
Fancy digital dash
The ability to change the responsivness on HST+ (stiff & instantly responsive or slow & soft)
Tilting steering wheel on the Grands
More options you can buy (air ride seat, more hydraulics, center PTO, etc.)
Adjustable width rims on R4s on the Grands vs fixed width on the economy machines
I had a L3200 (same as a L3301 only no emissions stuff) & upgraded to a L4040. I did it mostly for the cab, but also really enjoy the extra bells & whistles, not to mention the power & weight. It's a little less manuverable than the L3200 & loader visibility is worse, but I'm glad I upgraded.