Do I use 5w-30 or 10w-30?

[Zembonez]

I'm not saying you are wrong... I just never saw a 5.7 recommendation for 5w30

 

[PenguinLTZ]

I ran 5w30 Semi-Synthetic in my 95 Tahoe 5.7 to over 200K, and then switched to full synthetic 5w30 for the Alaskan winters after I drove it up there.

5w30 will do a 5.7 just fine, she had over 250K when I sold her for the new 'hoe.

That being said, I ran 10w30 semi synthetic in all my 5.7 /5.0 GMs when I live in WA, and pushed them all near the 200K mark without incident.

Maintenance will do your GM proud

 

[Zembonez]

I'll agree. 5W30 changed regularly won't hurt a thing. I just haven't seen it as recommended. Last 5.7 I owned was in my 97 Silverado. I actually ran 20W50 in all of my 5.7s. Never had any issues but we live in a very warm area.

 

[Bernie]

How many quarts? 6? Just split the difference and do 3 of each and get 7.5w-30

 

[Kennyray]

Smart ass

 

[Bernie]

Smart ass

I'm smart at both ends.

 

[Kennyray]

 

[Bernie]

Let's think about this a minute guys... Everyone here should understand what the numbers mean, so I won't explain them, but think about what time of year it is. Why worry about the right winter weight oil to use?

And, even if it was winter, it seldom drops below 0 degrees in Virginia, so 10w30 would be fine.

 

[sierra]

There is always much discussion over oil viscosity. I use 0W-30 in all my vehicles and always will. The lower the W viscosity the better the fuel economy when the engine is cold, not necessarily when the outside temp is. The lower the W number the faster the oil flows.

My 1996 Chevy 5.7L said 5W-30 on the cap, my 92 5.0L said 5W-30 on the cap. In 1996 AMSOIL came out with the 0W-30 and I immediately put it in my 1996 Silverado. 2nd owner has the truck now and approaching 200,000 miles.

I have the 0W-30 in 2008 GMC, my 2009 Cadillac CTS4 and if things work out, it will go in my 2010 GMC when it reaches 1,000 miles.

 

[OldCracker29]

I always used 5 qts of 5w30 in my '99 5.7. That's what it called for.