I own and operate my own tractor, for hire, to pull trailers.Right now with the ever increasing cost of diesel fuel, I find myself more than ever trying to cut corners on repairs.I have an worn out cummins 855 big-cam3.Oil alone leaves me with only 25lbs oil press max due to worn bearings, but with 4gallons of lucas plus 7gallonsoil to top off I run at a solid 40-45lbs.oil press.