hey im runnin a D15B7 with about 220,000 miles on it and its burning oil. up in the higher revs i can see smoke coming out my tail pipe. Im not positive that the smoke is black enough for it to be oil but i did check the dipstick and im loosing oil. I know some of you will tell me just get some money and get another motor but im trying to build my experience with motor rebuilding so i figure ill start with my trusty D series. does anyone know what seals would cause oil to burn in the higher RPMs.

the beast

 

if burning oil in higher rpms, i would lean towards piston oil rings. Valve seals you would see more on start up and decell while in gear.

 

thanks

 

a bad gasket, piston rings, can't really tell unless you open up the motor.

 

i just performed a head gasket change and torqued down to specs