Endrance

i have always put standard oil into my car for no good reason really just a small money saver. i want to start using synth now but ive always wondered if the changing rulkes applied to synth as they did to dino (every 3k or so). also. should i be using what it says on the oil cap because i've been reading around this part of the forum and it seems a lot of people are using either 5-w30 or 10w-30.

thanks in advance,
Endrance

DreamerGT

One of the main advantages of a synthetic oil is extended oil changes. Most run 5w-30 for the extra bit of protection. Was there a synthetic oil you had in mine?

Endrance

Well I was thinking mobil-1. It seems to be a popular synthetic an all I see are positive comments from people who use it. How much longer does it last about and also, will this help clean up my engine a bit from my old oil?

lizzyfan

The 3k oil change is a myth, even with dino oil

Unleashedbeast

Truth!

and there are hundreds of UOAs on the internet to prove your statement.

Original Poster:

Conventional oils (group II petroleum) and synthetic blends (group II blended with a little group IV) are good for 5,000-7,500 miles. Motorcraft syn/blend, etc...

Cheap synthetics (group III hydrocracked - highly refined petroleum) are good for a 7,500-10,000 mile change interval. Pennzoil, Mobil 1, Castrol, etc...

True synthetics (group IV PAO and V POE) are good for 15,000 or more, depending on the formulation. Red Line, Amsoil, Royal Purple, Mobil 1 EP, etc...

Endrance

Thanks for that info ill definitely be keeping that in mind. I kind of wanted to change the dino in my car already but its only been 2500 miles. I guess it can wait a 2or3 thousond more miles

everett

Unless you are going to follow the extended drain interval don't waste your money on synthetic. And disregard the 5w-20 spec. 5w-30 for sure

Unleashedbeast

Now now Everett....there are more reasons to choose a true synthetic than extended change intervals alone.

lower NOACK volatility (less burn off and evaporation)
higher levels of ZDDP (anti-wear additive)
lower friction (no impurities in the base stock)
lower heat (because of less friction)
etc....

everett

Ok ok beast. I know you know what your talking about. Op I retract my last comment.

03_mach_won

so whats the recommendation for a 4v motor? 5w20 on the oil cap or 5w30? or 10w30.. im at 70k miles.