I put 75,000 miles on w/15-w50 conventional, then went Whippled. After 15,000 miles, I switched to 10-w30 synthetic for one oil change. Now I took off the blower. What would happen if I went back to conventional?

 

Nothing.

 

agreed!

 

I was always told that I would have gasket issues, or even could lock up my motor b/c the having had the synthetic in at one time wouldn't let the new conventional bond to the metal.

 

the synthetic oil doesnt alter the properties of the metal.........

the old wives tale ussually goes the other way. saying that you will have problems with synthetics leaking from gaskets that wouldnt let dino leak from

i dunno about using that 15-50 oil tho. thats a lot thicker than what these things were designed to use

 

Synthetic oil molecules are smaller than conventional and all of the same size whereas conventional oil molecules vary in size. So, if you have a small oil leak using conventional it will tend to increase in amount using synthetic due to molecular make up. It will not cause a leak but will amplify an existing leak.

 

I run a 45 truck fleet of garbage trucks, so I just used to take what we run. The thickness is the reason that I went synthetic.