pilatti1

I have an '07 GT/CS that I am running synthetic motor oil (Penzoil). Any reccomendations for other better fluid changes? It is a 5-speed manual.

Thanks

Mikes_BLK_GT

mobil one, royal purple, amsoil to name a few, others on the forum use penzoil as well so I'm not convinced you really need to change unless you just want to.

algregory

In CA I was running Redline ATF and a 10% mix of Tufoil. I exchanged a note with Redline, they recommended to change at 30k. I'm now in NC, I changed to Amsoil ATF and a 10% mix of Tufoil at 30k. I had first changed the engine and 5 speed transmission fluids at 3.6k. "Tufoil" people I talked to said not to run before 5k miles, but I've been a synthetic oil user and a Tufoil user for years, couldn't wait anymore

Nuke

Amsoil, RP... ANY of the name brands. What's more important is that you maintain your fluids. Just about any decent brand will give you the same longevity provided you have acceptable fluid change frequencies.

ChiDiddy

i strictly stick with M1 and Amsoil. M1 is more readily accessible and usually cheaper at Walmart.

get an oil analysis done and see how well your oil choice is holding up.

blackstone-labs.com

Androdz2

First of all switch to 5w-30, 5w-20 was only recommended because of CAFE regulations and standards to raise the MPG of the fleet of vehicles. Second of all stay away from Royal Purple it does not meet the latest GF-4 standards and it is also not sm/sl Approved. If you want a specialty oil go with either amsoil or redline You can't go wrong with either. If you want to go with the mainstream go with mobil1. NOT all oils are the same do some reseach

Andrew

ChiDiddy

^yup. i agree. stay the hell away from Royal Purple. i've personally seen **** go wrong from it. And also tons of comparison tests proving RP is a subpar oil, even compared against Mobil1, which is proven to be solid.

I use a mix of 20 and 30 weight. 50/50

.boB

Here we go again. Unfortunatly, motor oil seems to be one of the greatest kept secrets in the gearhead world. Companies don't want to divulge anything other than what's on the label. And independant labs don't want to test it and reveal the secret. So you and I are stuck. So, there's a lot of mis-information flaoting around about various oils.

First off, what is synthetic? And what is NOT syntheitc. That's the first thing to understand. All oils start with a base stock. Group I, II, and III are highly refined dino oils. Anthing that uses a dino oil base stock, is a dino oil. Group IV is a PAO base stock, it is synthesized mostly from natural gas. This is synthetic oil.

Now, and interesting thing happened recently in this area. It was never given any press, and most gearheads don't know about it. Wall Street hired some lawyers and went to court. What it boils down to is that any oil that meets certain performance criteria can be called a "fully synthetic". It may have a group I, II, or III base stock (dino oil). But if it's refined enough and has enough additives, it can be made to perform like a synthetic, and can be called a "full synthetic".

You and I know that's not true. It's just another case of bait and switch. And you and I get bilked by paying PAO prices for group III oils. Groups in this catagory are Penzoil Quaker State, Castrol, and Mobile 1.

I use QS in my street cars. Seems to work just fine, and it's $1.50 a qt cheaper than M1. That doesn't sound like much, $1.50. But you do the math over 100,000 miles of oil changes.

M1 used to be a true synthetic. It was the first true synthetic PAO base stock motor oil introduced to the general market. But, that's no longer the case. You really have to dig to find the truth - if it can be found. But it appears that in the last few years, most of the standard auto grade oils are now Group III oils. Apparently, M1 found they could make a higher profit this way. It's still a good oil. But it's not a PAO true synthetic. It's not any better than Penzoil, QS, Castrol, etc. And it's not cheap. Although, I have seen it's price coming down as more people figure this out. Pep Boys had a pretty good sale last week end.

Mobile has also been "proven" as a good synthetic oil. Yes, sort of. Look at the dates on those test. Some of those tests are more than 10 years old. They were done when M1 was the new kid on the block. Now it's a differant oil, and those tests don't prove a thing.

Is M1 a good oil? Yeah, I think it is. It appears to perform as well as any other "true synthetic" oil on the market. But at $1.00-1.50 a qt more, it's not a very good value. But, that's just my opinion. I could be wrong.

So, now you're asking, "What oil is a true syntheitc (PAO)?" AFAIK, there are only three: Royal Purple, Redline, and Amsoil.

Amsoil seems to have a lot of good press, good test results, and feel good "information" available. But most of that seems to come from Amsoil, and people who sell Amsoil. That makes the data suspect.

Redline has excellent field experiance from all over the gearhead world. Seems to be good stuff. But sometimes hard to find.

Royal Purple is in the same boat. Excellent press. Excellent field reports. Sometimes hard to find. Fortunatly, my local Checker carries it; but it's cheaper to order it from Summit Racing. I use it in my track car. At the next oil change, I'll put it in my Harley. BTW, I'm holding a bottle of RP 10W-40 in my hand right now. It clearly has the API label, and clearly states GF-4.

Androdz2

10w-40 yes find a 5w-20 bottle to see BTW look up royal purple on most forums and see whats the concensus on it of people that have used it for racing (non-sponsored and non noob please). I have seen so many engines failing because of RP which is not even funny.

Andrew

Androdz2

Either way we should be running 5w-30 or even 10w-30 on our cars not 5w-20. The 5w-20 is recommended by ford only for the cafe standards.

Andrew