Im changing my car's oil, I want to know which oil is the best for a 96 z28?
Thanks

 

According to those who do oil analysis, the best oil at this time is the German made 0W30 Castrol Syntec. Search on patman, Castrol, and oildrop.

 

Thanks for the suggestion, I was wondering that myself!

 

fwiw I tried out the 0w40 Mobil1 on my last oil change and found my oil pressure has increased by 5-10 psi hot or cold. Also noticed the pressure is much more constant at WOT spurts than it used to be with the regular valvoline 5w30 I used to always use.

 

these 0w and 5w oils that start as mineral base stock are great if you wanna have the infamous lt1 spun bearing problems on high mileage cars. ill keep using 20w50(spring/fall) and sae 30(summer) and 10w30 in the cold.

 

Use what the General says in your owners manual.. The built and tested it and they should know.

 

I've always used Mobil 1, 5w-30.

 

20w50?! May as well put gear oil in your crankcase...

 

yeah, because a 20 weight oil is soooo thick. it obviously hurting the hp output of my stock motor.

 

Same here. The high perfomance blend from Mobil 1

 

Considering that the 0w and 5w are the viscosity's and not the thickness of the oil I suggest you should stop spreading bad rumors like this! I use German castrol 0w-30 in my car all year and it gives be better oil pressure hot or cold than Mobile 1 10w-30 or any other 10w-30 I have tried. JMO.

 

yes, it is. dont believe me. lets start with the first number. thats the oils thickness when cold. what do you think viscosity is? anyway, the stuff doesnt get thicker when hot. a 5w30 is a 5 weight that has 30 weight properties (thin out) when hot. dont believe me, get a quart of whatever 0w30 5w30 20w50 or whatever. put it in a container in the freezer, over night. then, turn your oven on to 200 degrees (normal operating temp for oil in most cars), then come back and tell me it thickens when hot. it wont.

 

Ditto.....10w30 in the winter, 5w30 summer....

no problems....

 

You have that backwards. Supposed to use the lighter weight(5w30) in the winter and 10w30 in the summer. That is if you choose to alternate like that.

 

http://theoildrop.server101.com/cgi/ultimatebb.cgi
M1 specifically 30wts. are too thin they are close to a 20wt. analysis PROVES that it is not the best choice for the LT1 and that 0w-30GC or 0w-40 M1 are better choices. Amsoils 30wts. are good choices too just not M1s 30wts. An oils ratings mean it falls in a weight range M1s oils tend to fall at the very thin end of the range and oil testing shows the LT1 likes thick 30wts to thin 40wts. You all want dyno and track numbers to back up[ performance mods yet you insist on ignorance with your oil. The analysis we speak of is like dynoing you oil it is actual testing to see how much wear metal is in there. The link above has lots of info including a whole section where people post the details of their car and it's use along with what oil and then the oils wear metal contents and measurements of how the oil itself is lasting. If you think you know more than that and are too pig headed to read and learn fine but don't try to tell others what is good because you are not educated enough to know what is good.

The General speced 5w-30 for CAFE reasons this same motor used in Europe or almost anywhere outside US and Canada specs 40wt., and GMs choice of M1 for the Vette was because they needed a synthetic for heat and Mobil was/is the biggest producer and you can bet GM and the others get something out of Mobil using them in advertizing too. M1 is good oil no doubt, the 30wts. just are not quite right for this motor.