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When to switch to Synthetic?


Full Member
May 26, 2007
I have a brand new 07 LTZ Avy and want to keep her for a long long time.
i run synthecic 5w 50 in my mustang and was wonering first off what grade synthetic to run? and when to make the change?

i plan on making my first oil change at 3000 km's to get rid of the metal parts that may be floating around?

i do live in canada so weather is extrem from -20 to plus 40 -  should it be wise to use different grades of synthetic for the weather?

thanks for any advice here
you can switch to synthetic any time you want regarless the mileage, in case you don't know, corvette z06  and cadillacs V series come with mobil 1 synthetic from factory, so you do the math , go ahead and change to synthetic
Switch to synthetic at the first oil change. Also consider switching to synthetic tranny fluid at the same time. The Diff has synthetic in it from the factory.
The tranny and transfer case all come with synthetic. The only thing that does not is the engine and front diff. So change to Synthetic and use the 5w-30 that is recommended. I live in Idaho and we very from -20 to 110. I have been using Syn since day 1 of buying my Av. I also use it in all my other vehicles.
My Datsun 78 280Z had 386k on Syn when I sold her, and she still ran awesome.

the diff's come from the factory with syn. oil already.the transfer case has special GM only fluid,the trans uses dexron 3 or 4,but it is still petroleum based so swapping to a true sythetic trans fluid is beneficial,the engine will also benefit just stick with the viscosity in your owners manual,you can change them all now,there's a myth out there that syn's don't let engine rings seat etc. the only reason not to run syn's from the get go is cost,should that engine have issues upon statup.
I made the switch late hehehehe at 32,xxx miles. Im using Royal Purple now.