Toro Timecutter SS4250

[chippy]

Recently purchased the Timecutter SS4250 down here in Australia. Its got the 24 HP 708CC Toro engine with the ZT2100 drive system.
It came with turf tires 18x7.5 -8 on a 5.5 rim.I have around 2 acres of some flat some sloping grass (not seeded lawn) in the country.
I am having trouble with it sliding and want to put some lumpier tires on it. I have been looking at some bar tread types and am not concerned with
damaging the natural grassland. I am concerned however these may damage the drive system,and also the only size tire I can get here is 18x8.5.
Would these go on a 5.5 rim. and what thoughts would you folk have on the effects to the hydro's.

 

[bertsmobile1]

Won't hurt the hydros so long as you are not 300Kg and towing a heavy trailer. :laughing:

Fitting the slightly narrower tyres should not be a problem but you might need to keep them harder to stop them rolling off the rims.
You can also get weights for the front which can help side slip a little.

 

[7394]

The optional wider tire you stated 18x8.5 is only 1 inch wider, they will fit fine. Inflated they might be a tad taller in the middle.