Which is best oil?

[OreoLT1]

What is the best oil weight to use for a 02 Z28 Lt1? 10W-30 full syn or 5w-30 full syn?

I've heard that using 10w-30 is a little better is this true.

What damege if any can you expect from using 10w-30 if it calls for 5w-30?

[ianwells100]

02 LT1??? shouldnt that be 02 LS1?

you should use what it tells you to use, however, your climate will effect your choice

i really wouldn't be too concerned about using 10w30 if 5w30 is preffered, however, i'd personally change to 5w30 next time

[Harrison]

Royal Purple Racing 21, Full Syn, Viscosity typical of 5w-30, should use a K&N oil filter too

[pr95blackbird]

amsoil is the best of the best, but its hella expensive

[OreoLT1]

So if it calls for 5w-30 if won't hurt to run 10w-30 for about 1500 miles?

[Fred]

Royal Purple 10w30. Thats what I use on my LS1.

[OreoLT1]

Did they not put the Lt1 in 02 Z28's?

[FireFighter]

Originally posted by OreoLT1:
Did they not put the Lt1 in 02 Z28's?

No, all 98+ f bodies had the ls1.


Also why is this in advance tech?

[terminaldegree]

Since it's summer and you're in Florida, you aren't hurting ANYTHING by running 10-30 instead of 5-30. In fact, the same oil in 10w-30 may last a little longer before it breaks down in the heat. The cold weather protection provided by 5 weight oil is completely irrelevant for that climate at this time of year.

I run whatever is on sale for synthetic that meets GM 4718M [the corvette spec], Xw-30, at 5000 mile intervals w/ oversize filter.

[terminaldegree]

btw, the "regular" Royal Purple isn't the same thing as the #21, and there are several varieties of Amsoil, some better than others, and there are two varieties of Mobil 1, and 3 kinds of Castrol synthetic in the same range of grades... And group 3, 5, and ester based synthetics like Redline. It's really complicated.

To add insult to injury, many of the best oil analysis results lately on bobistheoilguy.com are actually coming from less expensive "dino" oils like Havoline, and not the synthetics.