I'm new to this type of communication so please be patient with me. I drive an F350 with 7.3 PSD and I know a diesel is an oil burning engine. It will burn any oil from vegetable oil to lube oil. I have been burning used hydraulic oil and have had good results. I have installed an extra filter on the suction side of the transfer valve just to protect the valve and fuel pump from any possible debris that may get into the tank. I only use it in the front tank and have clocked about 15K miles on oil without any negative results. I was wondering if anyone else has had any experience along these lines and if you have had any problems.