Speaking of oiling the bearings, I should probably do that for my SP 7.5t. It's been used sporadically for a bit over 2,5 years prior to this summer, and more heavily this summer. Dusty clay mostly after the first 6 months, so a good cleaning and oiling would certainly be helpful in prolonging the bearing's lifespan. What sort of oil should it be? I have some oil sprays (silicone oil and gun oil for example), but I've heard there's dedicate bearing oils as well?