When can I switch to synthetic oil?

[4drsleeper]

I've just reaced the 3000 mile mark. I thought in the past I had read that you shouldn't switch to synthetic until 10,000 miles. Is this correct? I can't remember. I'd also like to change the trany and rear diff to synthetic...when can I do this.

[tollboothwilley]

most people don't swiitch til 7,500 - 10,000 miles...important to let the rings seat properly

[SVTCOBRA]

My local Infiniti dealer advised me to switch at 3K, so I did.

[joe603]

3k is fine. The main thing is to change the oil at the 1k mark to get rid of the break-in crud. The G also likes a heaver weight oil...I use 10W-40 synthetic (Royal Purple).

[marlin29311]

3k is fine. The main thing is to change the oil at the 1k mark to get rid of the break-in crud. The G also likes a heaver weight oil...I use 10W-40 synthetic (Royal Purple).

You also live where it's warm and can get away with 10W...

[joe603]

True...but it does get F'ing cold for a few months! I run the 10W synthetic all year round. The G doesn't burn/consume a drop!

[Sentientbydesign]

Disclaimer:

Running higher viscousity oil than the manufacturer intended can reduce fuel economy and power output.

[joe603]

She feels pretty quick...and I get 20 mpg's in mixed driving.

I would only use a good synthetic...

[tollboothwilley]

The G also likes a heaver weight oil...I use 10W-40 synthetic (Royal Purple).

I have heard this same thing from SEVERAL shops that deal almost exclusively with G35 and 350Z.