I see that most ppl have 285/35R22.
Just curious if 285/40s would work.

 

I use 295/30R22 Pirelli Scorpions. No fitment or speedo problems at all with my RUF wheels. 285/40R22 may cause speedometer problems. Make sure the tire diameter is within 1% to 3% of the OE tire diameter.

 

Comparing the overall diameter to that of the Transsyberia which ran a 265/65/18 with a o.d. of 31.56" The 285/40/22 is o.d. of 30.97" but is .79" wider than the 18's, so I don't know how that will affect tire rub towards the end of the steering range.