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Which Oil?

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This has probably been up for discusion before, but I'm getting ready for my 1st oil change. Not very versed on viscosity, weight and such, so looking for advice. My car is used for street only and used on sunny days only. Im in SouthEast Texas so summer here is very hot and dry...
 

ufnavy06

Some say he has a tattoo of his face on his face.
So far, I've just gone OEM with the Motorcraft. However, I'm about to switch to Amsoil as I've heard nothing but good things for years now. I've been meaning to do it for quite some time, but that time is now.
 
ufnavy06 said:
So far, I've just gone OEM with the Motorcraft. However, I'm about to switch to Amsoil as I've heard nothing but good things for years now. I've been meaning to do it for quite some time, but that time is now.
Im about to do the same also. I was also looking at going to royal pure for my next oil change
 
I just read the information on the different weights and types of Amsoil and I think the kind of driving I do, the signature series should be fine...I had a 69 Chevelle that I ran Joe Gibbs in and a really good oil does deffinately make a difference and gives you a piece of mind when you empty it and it's almost as clear as is was when you put it in...thanks for the input guys...
 

ace72ace

Zaino, I put that $hit on everything
1,242
71
I was gonna go the Amsoil route too after reading a ton of threads on this. Thanks for the reminder on this topic, now that Xmas is over, I have to send in my OEM Motorcrap fill to the lab for analysis. I'm sure that replacing it with the same is ok for the street, but the for the same money there's much better stuff out there, Amsoil, RP, or Redline. The added protection you get from a 'full synthetic' versus other brands that will shear much more quickly.

That being said, end of last summer there was a killer deal at Pep Boys on Royal Purple. They had a 35$ off coupon for 5 quarts + filter, final cost 29.99$ As our cars take 8.5 qts, I used 5 coupons to get 25qts. So I'm just a half quart short on my 3rd fill, easy enough to pick up another. Will keep my eyes open for this deal again. Can't beat a change with full synthetic for $60 plus extra filter. Pep Boys charges 9.99$ for the filter alone. :D

Check out some of the old oil change threads. I added Fumoto valve and bought the form-a-funnel, very glad I have both. Will also do another oil analysis later this year when the RP fill is at the same mileage as the Motorcrap for a direct 1-1 comparison.
 

PeteInCT

#LS-378 - So many Porsche's, so little time....
Moderator
2,848
14
Connecticut
Guys,

From everything I read and hear AMSOIL is an excellent oil. However, as far as I know AMSOIL still does not make a 5W-50 weight oil. There has been a lot of forum discussion on this over the last year. Long story short, I personally would not use anything other than a good quality fully synthetic 5W-50 weight oil (Full disclosure: Some forum members have used different weight oil and so far no one has made any connections to problems AFAIK). Ford has stressed this point emphatically, and I really don't think it is because they are just trying to sell Motorcraft oil (they do not state that you must use their brand). Our engine variable valve timing system uses a solenoid managed valve that controls engine timing, hence the quality and weight of the oil we use play a key factor in long engine life. The fact that we redline at 7500 at almost full engine power also bears weight on this.

Long story short, and especially if you do not track your car, I'd stick with Motorcraft oil (or similar, I personally use Castrol Syntec Edge) and just change the oil and filter frequently, maybe every 3000 miles. Once the oil starts to get dirty it's your enemy and no oil formulation is going to counteract that.

FYI - Royal Purple uses graphite in their formula AFAIK, and some say that's bad for the long term whereas other drivers swear by it. Where the truth lies IDK, but I'm not willing to try it and find out the hard way unless I can see some empirical evidence that it does more harm than good.

-Pete
 

Sesshomurai

PeteInCT said:
Guys,

From everything I read and hear AMSOIL is an excellent oil. However, as far as I know AMSOIL still does not make a 5W-50 weight oil. There has been a lot of forum discussion on this over the last year. Long story short, I personally would not use anything other than a good quality fully synthetic 5W-50 weight oil (Full disclosure: Some forum members have used different weight oil and so far no one has made any connections to problems AFAIK). Ford has stressed this point emphatically, and I really don't think it is because they are just trying to sell Motorcraft oil (they do not state that you must use their brand). Our engine variable valve timing system uses a solenoid managed valve that controls engine timing, hence the quality and weight of the oil we use play a key factor in long engine life. The fact that we redline at 7500 at almost full engine power also bears weight on this.

Long story short, and especially if you do not track your car, I'd stick with Motorcraft oil (or similar, I personally use Castrol Syntec Edge) and just change the oil and filter frequently, maybe every 3000 miles. Once the oil starts to get dirty it's your enemy and no oil formulation is going to counteract that.

FYI - Royal Purple uses graphite in their formula AFAIK, and some say that's bad for the long term whereas other drivers swear by it. Where the truth lies IDK, but I'm not willing to try it and find out the hard way unless I can see some empirical evidence that it does more harm than good.

-Pete

+1
 

PeteInCT

#LS-378 - So many Porsche's, so little time....
Moderator
2,848
14
Connecticut
PS: To add to this, if AMSOIL did make a 5w-50 oil I would do some more research and very possibly use it in dedicated track cars.

-Pete
 

ace72ace

Zaino, I put that $hit on everything
1,242
71
Hey Pete, I fully understand your position and how you have weighed the options and formed your own opinion. I heard also about the additives in RP supposedly being 'bad' for the cats in the exhaust. My Boss doesn't seem to burn hardly any oil at all, the level only moved down the cross hatch on the dipstick maybe 1/4" over 6200 miles of street driving, no track events. So for the folks that are either burning 'a lot' of oil or are catching a fair amount of oil in a catch can, then the RP additives could be a cause for concern.

I struggled with the RP decision versus Amsoil because of the viscosity debate. You raise very valid concerns about deviating what is recommended by the manufacturer, as well as possible warranty implications if you tend to err on the side of caution and take a more conservative approach. Now with that being said, I've read dozens and dozens of oil threads, paying particular attention to viscosity discussions.

There are no hard and fast standardized metrics for determining viscosity ratings. Manufacturers can rate their oils however they please. Much like shoe sizes, and other clothing manufacturers vary, so do oil ratings. Here's my #1 reason for 'risking it' going with RP over 50 weight Motorcraft.

If Motorcraft quickly sheers down to a 40 weight in as little as 2500 miles or less, then why doesn't Ford recommend an oil change interval that ensures that the synthetic oil stays at the original viscosity for the recommended service life of the oil? Going by the Oil Life Meter in my '13, I am guesstimating that the factory fill would have started prompting me for a change somewhere north of 7.5k-8k miles. So if it really sheers down to a 40 weight after about 25-30% of its usable service life, then why aren't I damaging my engine from miles 2500-7500? Because I'm not. That's my story and I'm sticking to it. ;)

Nobody has been able to answer that question. Why? Because in my mind it's a non-issue. Never mind the switch from 5-20 to 5-50 on the other 5.0 engines, we'll just keep on topic with the Boss engine. My wife's 11 GT has the 'oil squirters' that the newer engines don't. She will keep taking her car to the dealer for Motorcrap changes, as they warranty her engine to 100k miles by doing so.

So there you have it, no big drama or conspiracy theory, just my own personal, non-expert opinion based on the facts at hand. I would be willing to bet a good case of beer that the engine oil analysis from my RP at the exact same mileage compared to the Motorcraft will show superior results.

Ford only has to recommend an oil that is good enough to get through the warranty period, and I'm sure their brand is 'good enough'. I plan on owning my Boss well past the warranty, so I've made my choice and am confident I will not have any issues related to viscosity. I am tempted to purchase some Amsoil for my next fill and then get an analysis done so I will have results for all 3 brands...

Let the flame war begin!
 

ace72ace

Zaino, I put that $hit on everything
1,242
71
Sure thing. I plan on sending my results over the oil guru over on SVT Forum, UB really seems to live for a good healthy oil discussion. Never mind bible study, we are going to debate additives next Tuesday night over tea & biscuits! ;D
 
Wow, I guess I should have asked what the best windshield wash is instead of oil??..lol...but it's great to get the opinions of those that are, at least, somewhat educated in viscosity and have put time in studying different products. I have always been the kind of guy that believed as long as it was slick, it was working, so I am really paying attention to all the great information...
 
DKL,
I had this debate with myself when I was up for my first oil change on my '12 BOSS. I chose Mobil 1 5w-50 and I got it from Napa, and at a good price too. I use a Motorcraft oil filter (stock specified part). I change my own oil and really thought to myself that I've used this oil (Mobil 1 brand) for a long time and have used it in everything from turbo 4 bangers to old chrysler slant 6 engines. It's never let me down. I Probably owe it to the fact that I perform routine oil changes. Thats probably the most important thing, a routine/faithful oil change. I don't think a Ford service department would deny any warranty work for not using the Motorcraft oil, as long as you have receipts/records of good major brand oil and oil filter used in your Boss' oil changes.
 
BOSS2664 said:
DKL,
I had this debate with myself when I was up for my first oil change on my '12 BOSS. I chose Mobil 1 5w-50 and I got it from Napa, and at a good price too. I use a Motorcraft oil filter (stock specified part). I change my own oil and really thought to myself that I've used this oil (Mobil 1 brand) for a long time and have used it in everything from turbo 4 bangers to old chrysler slant 6 engines. It's never let me down. I Probably owe it to the fact that I perform routine oil changes. Thats probably the most important thing, a routine/faithful oil change. I don't think a Ford service department would deny any warranty work for not using the Motorcraft oil, as long as you have receipts/records of good major brand oil and oil filter used in your Boss' oil changes.


I had actually thought that Mobil 1 would be the one I was going to use. I have pretty much used Penzoil in my truck and my wife's car, mostly because the quick lube shops all have it. I have always changed oil in all of my vehicles at 3000 miles, except for the 69 Chevelle, it was always sooner because of the way I drove it. I have always heard good things about Mobile 1 and a car like this deserves only the best. That is why I wanted to get opinions from guys I figured had the answers...Thank you sir...
 

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