2008 Pontiac Grand Prix V6 what oil?

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Have a new addition to the family. Pontiac Grand Prix 3.8L V6 with 66k. What would be a good oil for this engine?
 
Nice.

What oil has been in it? If ya don't know I'd do a UOA...

What's your maintenance plan, & desired OCI?
 
Originally Posted By: tpitcher
Nice.

What oil has been in it? If ya don't know I'd do a UOA...

What's your maintenance plan, & desired OCI?


Just picked it up today. No idea whats in it. Has a Valvoline filter. OLM is at 89, according to the service sticker has 1500 on the oil. Would like a 6 month synthetic OCI. Mileage should be about 15k a year. 50/50 highway/city.
 
All of the 3800s I`ve owned have specd 10W30. Vwb,pyb,gtx,etc would be perfect imo. Or since you said you want to do synth,go with the synth versions of these in 10W30.
 
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Ok. PP, PU, M1 or Amsoil would all be excellent choices.

Keep a quality filter in that baby!
 
Keep a close eye on it...I've seen several of those use 1qt/1000-1500 miles. No rhyme or reason to it from I've been able to figure. I've seen those come in since new and get religious oil changes on time, even early by standards here at 3,000, and still be using oil. Others don't seem to use a drop. My 07 uses about a 1/2 quart over 5000-6000 miles.

With that goal in mind, I'd probably run Mobil1 EP (I do believe in a little overkill) and use a Wix or PureOne filter.
 
Those motors are pretty stout. I would go for whichever 5w30 + filter is on sale at the time. As for dino vs syn, that's your decision.
 
My mom has a 05 that was using about 1.5qts in a 5000 mile run. I swapped to Motorcraft 5w-30 and saw consumption drop considerably. That's been what I've been using every since.
 
Pretty much any name brand 5W/10W-30 will suffice in these engines. It's what you want to spend. Personally, I'd use a Dexos1 rated synthetic like Mobil 1, QSUD, or any of the other SOPUS offerings...
 
Anything 10w30 with a quality filter and the engine won't care. I've run just about every oil out there in my 3800 II and every UOA has come back looking fine.
 
The 3800 is a nice strong engine with plenty of low end grunt.

These engines had a lot of problems (intake manifolds burning or warping, cam sensor magnets dissolving in oil, coolant bypass tubes snapping, too much torque for the trans they're mated to) early on but by 2008 that was all dealt with. The supercharged 3800s could develop oil consumption problems, but with an NA version you're cool there too.

The only common problem you should be at risk of would be the little rod bearing issue they had. It was never really common enough to get fixed, but if you don't run Xw20 oil in it or race it you should be fine.
 
MY 2005 grand prix had 5w-30 on the oil cap. I believe they switched from 10w-30 to 5w-30 when the series III 3.8L came out, in 2003-2004 irrc
 
Have no idea how accurate the OLM is. Suspect its in the range of 7-10k like most. Rather than ignore it would be nice to use it changing at (for example) 10%. Would PU 5w30 would be OK for 7500-8k OCI?
 
Originally Posted By: LeakySeals
Have no idea how accurate the OLM is. Suspect its in the range of 7-10k like most. Rather than ignore it would be nice to use it changing at (for example) 10%. Would PU 5w30 would be OK for 7500-8k OCI?


Yes - good choice.

I would also consider Mobil-1 and Amsoil. A Pure One filter should be included also.
 
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