switching back to conventional after using synthetic?

[PSDan000]

ive always used conventional oil in my truck (rotella 15w-40) and i switched to rotella synthetic on the last oil change. went to get oil today and they were out of synthetic so i said screw it and got the 15w-40. would it be ok to switch back? thanks

dan

 

[budtoh3zo]

It wont hurt anything go for it

 

[sagebel]

I have heard this theory from a few engine builders and mechanics: The oil molecules in dino are random in size (large, small, etc...) where as synthetic molecules and consistanly sized. The theory is that the seals on the engine will be permeated with the one size only synthetic and then when you switch over to or back to dino the smaller will leak through. I did revert back to dino on a gasser I had and it did start leaking. Any other thoughts on this or am I just misinformed?

Scott

 

[budtoh3zo]

it can happen, but i have never, i switch every winter and spring, no problems yet, the only thing i do is trow in a bottle of seal treater then it soffens the seals up. I also do it on my IDI lots older seals in there and no problems.