Engine Oil

I Own A 2004 Silverado Ls. 15000 Miles

I Was Wondering Are You Guys Using 5w30 Oil As Indicated In The Engine Or Using Another Grade? In My Opinon Its A Very Lightweight Oil Specially If You Drive In Hot Weather Always As I Do Here In Texas.

The Guy At Autozone Recomended I Add 1 Quart Lucas Oil Synthetic To Each Oil Change And That Would Give Extra Protection.

Thanks...

Well what kind of oil are you using in the first place? If your running a synthetic oil you should be fine. That Lucas stuff does help but if you run a good synthetic such as Valvoline, or even RP then I'm sure you'd be just fine.

Read this.

http://www.automotiveforums.com/vbulletin/showthread.php?t=388147&highlight=oil

I use what the engine recommends - 5w30 because i read in a tech bullitin (sp) that if you use any heavier oil, sometimes its too thick to get in the small orifices and oil tunnels where it needs to and some parts of the engine are poorly lubricated. I figured that GM tested it and if they recommend 5w30, might as well use it.

the lighter oil only has to due with emmissions. my 88 chev has 462000 klm's on it and i have used quaker state 10w-30 in it since day one

use the recommended wieght per GM but use a synthetic. i live in texas as well and synthetic oil does not break down due to heat like petroleum oils. and the lower viscousity will give you slightly better gas mileage though probably not low enough to make a big difference but with prices the way they are for gas every little bit helps. also read the link that Jethro 3 responded with it is a book basically put on line everything you ever wanted to know about oil and then some.

use the recommended wieght per GM but use a synthetic. i live in texas as well and synthetic oil does not break down due to heat like petroleum oils. and the lower viscousity will give you slightly better gas mileage though probably not low enough to make a big difference but with prices the way they are for gas every little bit helps. also read the link that Jethro 3 responded with it is a book basically put on line everything you ever wanted to know about oil and then some.

Ditto on the synthetic. In addition to the thermal breakdown protection, I believe it helps starting on those zero degree mornings up here in winter.

Bought a used '91 with 60K on a v6 and a knock in a wrist pin. Put in synthetic and sold that truck with no engine problems at 180K. The next owner got that truck to 300K before it was totaled by an accident. That engine would get 20 in the city and 25 on the highway with the AC on, never gave any problems and never had more than a starter replaced. Synthetic is the only way to go.....

Anyone use Royal Purple? Why is that stuff so expensive?

Anyone use Royal Purple? Why is that stuff so expensive?


Because it's possible that it's about the best synthetic oil out there. I rate it higher than AMsoil too but I've never done testing on them.

read this it will tell you everything. I mean EVERYTHING. it starts on page 17 http://www.trustmymechanic.com/motor-oil-bible.pdf