98RedBird

iTrader: (77)

hey i was wondering what oil weight to go with, i am going to get mobil 1 because from what i hear from most of you guys, it IS AMAZING. right now where i live it is about 90F, and i was thinking about getting 0w30 but i think since it's so hot out maybe i should just get 5w30. they also make a 0w40. what do you guys think. with it hurt the car having 0w30 and 90F temperatures?? thanks

Tranzor

If you're going to go with Mobil 1, stick to the 0w40. It offers the best protection for our application, since Mobil 1's 30 weight is on the thin side of the 30 weight spectrum.

Check out this website, there's lots of good oil info there: www.bobistheoilguy.com. Also, if you have oil questions go ahead and give a shout out to Patman, that guy is the resident LS1TECH oil guru.

My recommendation is to just make sure to use a good oil, no matter the brand. Amsoil, Redline, Mobil 1, Royal Purple, and Castrol (the German brew) are the cream of the crop. If you are interested in giving Amsoil a try, let me know... I'm an independent dealer and can give a good price for fellow LS1TECH members shipped direct. I just can't post prices, so shoot me a PM if you want to know more or just have some questions.

natronathon

0w-40 will be better for high temp protection than 0w-30. This is a great oil. I run it all year round, And I see temps from -5 - 100+ as far as the weather is concerned. You will love it. Its awesome for extreme temps on both ends of the scale!

shouldaboughttheZ

iTrader: (8)

I run the Royal Purple and love it. I used to run Mobil 1 10w30. You will find alot of opinions on here on what to use. I would take Tranzor's advise and do some checking around.

blkZ28spt

And you could/should have tried searching. This thread https://ls1tech.com/forums/general-maintenance-repairs/339677-oil-weights-grades.html is two below yours right now.

BriancWS6

iTrader: (18)

Mobil 1 0w40 here as well

Patman

Another good choice if you decide on Mobil 1 is their new 10w40 Extended Performance. I definitely think their 5w30 and 10w30 are not the best choice for the LS1, since they are both on the low side of the 30wt range. So they don't offer a good HTHS (high temperature high sheer) number for hard driving.

natronathon

where is the HTHS rating found on the bottle? is it on the bottle? Or does this refer to the weight?

Patman

You won't find the HTHS rating on the bottle, it's something that you will often find on the manufacturer's website. Often it won't be there though, and you need to find it through other resources (such as emailing or phoning their technical support line)

Mobil 1's HTHS is only about 3.1 for their 5w30 and 10w30, while GC 0w30 has an HTHS of 3.6.

natronathon

Do you know off the top of your head what the HTHS rating for Mobil 1 0w-40 is? What is the scale for the these numbers? is 3.6 drastically better than 3.1?

EDIT: I actually just found the HTHS rating for Mobil 1 0W-40 on their website. It is 3.6. How good is 3.6?

Thanks

blkZ28spt

I'd also like to know this. Never heard of HTHS before. I'm trying to treat my motor right to make up for all the time I was running standard valvoline and Fram filters.

jorgez28

what is the best weight for 100 degree weather?

98DroptopSS

iTrader: (2)

I'm curious too?

natronathon

damn, patman... you're popular! You're the man with the knowledge on this issue!

Patman

3.6 is a very good number for a 30wt oil, but to be honest, it's not that great of a number for a 40wt oil. Most 40wt oils have HTHS numbers of 4.0 or higher. But a number like 3.6 is definitely going to protect your engine better than one of 3.1, especially if you see high oil temps very often (such as if you road race)

Tranzor

I think most people agree with ya on that. I'm an Amsoil dealer and I do a lot of reading about oil, and I'm still learning quite a bit from his posts... Patman has forgotten way more about oil than I think I'll probably ever figure out.

why2kmax

Im using 0w-40 M1 now, but Im finding 5w-40 M1 for trucks and suvs a LOT easier and cheaper. Looks almosst the same, bit thicker. and a lot like their delvac 5-40.

any thoughts on if this would be as good or beter than the 0-40?

cst vi at 40/ and 100c/ VI / HTHS
5-30 40c 56 100c 10.0/ 175/ 3.08
0-40 40c 80 100c 14.3/ 187/ 3.6
5-40 40c 103 100c 14.8/ 151/ 4.1

Mr Incredible

Just wondering, for those that use their vehicles as a daily driver, don't road race, don't mash the gas at EVERY opportunity, are mostly sedate, and don't drive in Arizona, Nevada, Texas, or other HOT places.......wouldn't a 5w-30 or 10w-30 be just fine?

Obviously, practically any middle of the road weight oil (throwing out the extreme thin and thick) will work just fine. 5w & 10w-30 are standard weights for many performance vehicles. And, just as obviously, everyone is looking for an intelligent decision when it comes to picking something off the shelf. But is 0w or 10w-40 splitting hairs or is it that much better for the non-extreme driver?

I'll drop something in a minute if I see an item that is the same price but offers better performance. But it's often that next question not being asked that bites us in the butt - What is offered that may NOT be better or negates the perceived upgrade.

It all comes down to our personal choices, but, again, just wondering...

Patman

You are correct, if you simply drive your car sedately, and rarely go full throttle, then you would do just fine with Mobil 1 5w30 or 10w30.

ashzero

chalk up another one for mobil 1 0w40

i've used 5w30, then on the previous oil change i went 10w30. i noticed the car developed a minor "clacking" sound at low rpm with the 10w30. did some more research and updated my brain with new oil weight information from the interweb, and went 0w40 this time. started her up, and it was very smooth and quiet. no more "clacking" sound.