Why are some of you guys using higher weight oils? ie 15-40 I was always told the lower number of the two is the thickness when cold and the higher is the thickness when hot. Nissan recommends 5-30 so why use something like 15-40? If anything I would use 0-30 or if your turbo and your engine runs hotter maybe 0-40.

 

The amsoil is a 5w30

 

Rotella T-Syn 5W40. I've got the blackstone used oil analyses to show how good it is!!!

 

amsoil 5w-40 diesel.... it has a bit more zinc and may be rough on the cats tho i heard.... test pipes it is!!!

 

Wal-mart was out the last few times I checked for M1, but got it at Target for $5.99 per qrt.

 

Pennzoil Platinum and Valvoline Synpower, both 5W-30. It likes German Castrol Syntec 0W-30 also.

 

Built motor and boosted.

 

I'm using 0w30 M1 syn on my G

 

what does the G35 have stock? synthetic or traditional? i've always bought high mileage cars and have been afraid to switch to synthetic. i was always told that if you've got leaks that are gunked up, the synthetic will leak easier.

With the G35 (57700 miles) I want to try synthetic if that's what's in there or switch over if it's not. Any suggestions?

-James

 

Does Infiniti have a contract with Kendall oil? Here in my city and in OH where I have relatives, they always use Kendall GT-1 Syn.

I hear you guys talk about Pennzoil & Amsoil and makes me wonder why Infiniti doens't use these.

 

no, they are just using it probably b/c it's cheap... i've been to three infiniti dealers, and two used mob-1, the other uses penzoil.
http://www.rateitall.com/i-240860-ke...motor-oil.aspx

mixed ratings on that stuff, idk if i would trust it in my G...

 

I don't trust Penzoil in my lawn mower....

I've always used Mobil 1 up until the G. Now it's nothing but the best, Amsoil.

 

mobil 1 5W30.

i've always found it humorous how dealers push $ynthetic oil$ when the Infiniti owner's manual clearly states that synthetic oils are not to be used in our engines. at least my '04 manual says that...

 

What's not to trust about Pennzoil? Pennzoil Platinum typically gets good UOA numbers.

 

The myth that is commonly told is that using synthetic in a high mileage engine will cause oil leaks. This is not really true, Synthetic has more detergents in it so it cleans better than conventional oil. That being said if you have seals or gaskets that are worn and there is gunk built up on them keeping them from leaking than yes the synthetic could cause them to leak. However with only 57K on your G I would absolutely switch. If you go with Amsoil there is a engine flush that you can just add to your old oil and let the motor run for 15-20 mins, then drain and fill with Amsoil, you do however replace the old filter before the flush and then install another new filter after. You can use a cheap Fram filter, they instruct you to change the filter so that you are not disolving the junk in the filter and spreading it through the motor. After draining the old oil and flush you then can install a Amsoil filter. I would say that the only reason do use the flush would be if you have been visiting oil change places and not changing the oil yourself with quality oil and filters.