New guy with old questions I'm sure

**bpm4x4** · 05-13-2009

Just got a 08 Grand Prix 3.8 NA and right before my first oil change on it, the check oil light comes on.......it's 1.5 qts low!! is that normal?? We traded in a Buick Regal 02 (very similar under the hood) with 167,000 miles on it and it didn't use more than 1/2 quart of oil between oil changes. I ran Shell 10-30 in the Buick, but this one says to use 5-30, Why?? It's not getting better gas mileage than the Buick, so whats up with this car?? (it has 29,000 miles on it now) I also just noticed a small oil leak--something else that Buick did not do.

**Bio248** · 05-13-2009

any smoke from the exhaust? blue colored?

**bpm4x4** · 05-14-2009

Originally Posted by Bio248

any smoke from the exhaust? blue colored?

no, it runs fine and has plenty of power, I just don't see why I can't run 10-30 in it.

**Scimmia** · 05-14-2009

You can, but as they're both 30 weight oils, it won't make a difference unless you're running really cheap oil, and even then it really isn't much different if it's SM rated. There is something else going on with this engine. There are only a few places it could be going, leaking into the combustion chamber and getting burnt, leaking out onto the ground, or leaking into the cooling system. You need to figure out which one we're talking about.

**Bio248** · 05-14-2009

10-30 is thicker, so it is probably better anyway.

**Scimmia** · 05-14-2009

Originally Posted by Bio248

10-30 is thicker, so it is probably better anyway.

Oh really? So Mobil1 10W-30 at 10.0 cSt is thicker than M1 5W-30 at 11.3 cSt?

That's a gross generalization that doesn't hold true.

**Bio248** · 05-14-2009

meh, i run 10w-40.

on 5w30 my motor probably would have less than 5 psi of oil pressure at idle. with 10w-30 i would have maybe 8 psi at most at idle.

my motor has taken quite a beating from me driving it everyday.

**bpm4x4** · 05-14-2009

Next oil change I am switching to 10-30, I talked to the dealer (its nice to have a warranty) and they are going to look at it on Tuesday. I asked them about the oil and was strongly cautioned about running 10-40, but 10-30 was fine. The service manager might just be covering his @$$, so it's 10-30 summer and 5-30 winter for me.

I really think it's just leaking around the pan, or valve cover. Do these engines need to "wear in??" this is the lowest mileage car I have ever owned.

**Scimmia** · 05-14-2009

If you want a thicker oil, be careful, as I pointed out earlier, 10W30 isn't always thicker. Hell, I run a 0W-30 that's thicker than just about any other 30 weight on the market.

**bpm4x4** · 05-21-2009

Just a little update, they put in dye and want us to bring it back. They also said I did not have the drain plug tight enough, so I may get a 3/8 torque wrench (I have never torqued a drain plug and have never had one come out, so I think it is a little silly to get one). Whoever did the last oil change had the drain plug so tight I had to use my foot (size 13) to get it loose.