twill220

i was a 1/2 quart low on oil and added that much of oil not remembering i just switch to synthetic oil in march. will this effect the engine and performance or is it basically oil is oil?

Skirmich

Oil is Oil you just wont get the Full Benefits of 100% Syn in the Engine.

fsttyms1

You mean you last changed your oil in march to syn, or you started using syn in march but have changed it since?

But to answer your question yes you can mix them, BUT if you are on extended change intervals I wouldn't mix them unless an emergency or you plan on changing it soon. It won't hurt it, but it will reduce the long interval properties of the syn.

3.2TLc

Hey Twill220, has your motor always used or lost a 1/2 quart before the switch to synthetic ? If your TL is aging and has been used to conventional oil, the syn may find it's way through weak gaskets and seals more quickly than dino, IMO.

How many miles are presently on your TL and what is the frequency of miles between oil changes ?

Check for any apparent oil leaks or seepage. Did you put in a full 5 qts. @ last oil & filter change ?