Help me choose between 4 types of oil

[Gator]

My vehichles are dailly drivers 15 miles each way and either longer or more driving on weekends. Vehichles are a 2006 mustang GT, 3.8 pontiac boneeville, and a vortec 350.
My 4 oil choices are Pennzoil Platinum which is 18.75 for 5 quarts. Pennzoil Ultra, Mobil 1 5w30 either high mileage or EP, and Mobil 1 0w40. I am wanting to change oil a minimum every 7,500 miles and a maximum of 10,000 miles,

the 0w40 may be the best but will it work in the Mustang v-8 since it recommends 5w20.
Can you guys tell me why a certain oil is better like the difference in the plat and the 0w40 as group 3 or what ever.

 

[ARCOgraphite]

Why are you limited to those four oil choices? No Kendall?

 

[LeakySeals]

For the 3 I would go with the M1 5w30 or the PU 5w30

 

[zyxelenator]

Whichever is on sale/rebate

 

[eagle23]

I understand the Fords don't like thicker oils, so I don't know that I'd go any thicker than 30 wt on the top end for that one. If the others are approved for 20 wt, I'd use that for all and sleep well.

I'm also biased toward PU but that's me. Mobil1 is really good stuff.

 

[teddyboy]

If it were my car, I'd run the viscosities recommended for the cars which would be 5W30 for the Pontiac and 5W20 for the Ford (although 0W20 would work fine for the Ford). I'd buy 5 qt jugs of M1 in the appropriate viscosities at Wally World for $27.19.

 

[fdcg27]

$18.75 for the PP makes that a good choice.
In your climate, I doubt that the Mustang would be hurt by a 5W-30, but you could just use the recommended 5W-20 in it.
PP will certainly go for 7.5K, and looking at residual TBN in the UOA forum for various engines, it might be capable of 10K in certain applications and use patterns, although SOPUS does not promote either Plat or Ultra as long drain oils.
A UOA at 7.5K would tell you how much TBN remains for each engine at that point, as well as how well viscosity has held up, and you could then decide how much longer you could safely go.

 

[TFB1]

I you "gag" that Stang regularly(like I would), go with the 5W-30, if you drive more moderately the 5W-20 is fine... I use M1 0W-40 in my Marauder cause it gets beat on like a whippin' boy...

 

[Gator]

Thanks for the replies, I have been using Pennzoil Platinum 5w30 for the last couple of years and have been changing anywhere from 5,000 to 7,500. A few dollars extra each change 2 changes a year is no big deal. I just noticed that the Mobil 1 0w40 has a very nice additive package and a healthy 12.0 TBN to start with and figured it might be better in all applications except the Mustang. I was reading on a corvette forum that the 0w40 never reach a 40 weight in normal driving due to the oil temp never getting hot enough. The guy was saying he had questioned Mobil and that was the answer he got. I have also heard the Mustang has to get the oil up to the top quick for the timing chain or valve timing adjusters or something like that.

 

[HTSS_TR]

For normal driving the oil temperature is rarely get above 180-190F, you don't want thicker oil than recommended by manufactures. For your Mustang I would go with M1 0W20, PP 0W20(if available) or 5W20, or any synthetic xW20 with 8-10k miles OCI if most your trips are more than 10-15 miles.

For the Pontiac, any synthetic 0-5W30 will be good for 8-10k miles OCI.

 

[Will41]

Originally Posted By: Gator

My 4 oil choices are Pennzoil Platinum which is 18.75 for 5 quarts.


That is really cheap! It is $24.95 around here.

 

[ARCOgraphite]

Originally Posted By: Gator
I was reading on a corvette forum that the 0w40 never reach a 40 weight in normal driving due to the oil temp never getting hot enough. ....
If its a 40 how could it be anything else? All oil viscosity varies with temps ( and stressors) and gets thinner as it warms up or is sheared. The viscosity is measured at 100C, which in unstressed driving is typically hotter than the sump temp. So a cold 30 (say 80c)will be thicker than a hot 40(say 110c). Seems to be some basic misunderstanding of oil here.

 

[Gator]

I don't no that is what I read, but I think a 0w40, the 0 is for cold start up and the 40 is for the full temp running engine. I guess the corvette with high sump capacity and oil coolers just cruising the oil was in a 170 to 180 F range. I thought the oil had additives that keeps the oil from thinning out at full temp. or am I wrong, surely it aint a 40w0 oil 40 at cold start up and a 0 thin at full operating temp.

 

[ARCOgraphite]

Originally Posted By: Gator
surely it aint a 40w0 oil 40 at cold start up and a 0 thin at full operating temp.
Its about 35,000 cP at -40F and 70 cSt at ~100F, then ~14 cSt at 212F moderate sump temp. I think what you're saying is, if you have a cold running sump temp (as in the corvette example) you can run a thinner oil to begin with. Ltes say we're racing at Lime Rock

If you would normally run a SAE40 with a 230F sump, you could now run a SAE30 if that sump was held to 200F MAX with an oil cooler, Magnesium 8qt pan, etc.
Now, the "additives" you speak of (VII polymers) coil up and "go to sleep' when its cold allowing the oil to still flow when very cold, but they uncoil and inhibit drastic viscosity loss as temperature increases. This is a Multigrade oil by definition. The O/5/10/20W is not necessarilay a SAE graded weight, but you can think of it (in a 5w30 example) where as in the old days where you might run a straight grade SAE10W in a cold Winter, you can now run a 5W-XX multigrade without the penalty of having a "too thin" oil at high sump temps as you would with the single grade.