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10w30 oil in the FiST

Jerickson88

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#1
So, I’ve used the Motorcraft Synthetic Blend since I’ve had the car and the Motorcraft Filter.

The company I work for stocks our vans with Mobil Special 10w30, which is also a synthetic blend. My car is stock as a rock, I live in Alabama, where it’s frigid maybe a month or two out of the year. I can get this oil free (ethically)

Is there a reason I shouldn’t? I get that our cap says 5w20.

Im not so broke I can’t afford the Motorcraft from WalMart for $20. I’d obviously use the Motorcraft filter..
 


Ford ST

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#2
10w30 is pretty heavy to start out with and a lot of people use it as an alternative to straight 30 weight for lawn equipment. 0w30, or a 5w30 at least start out thinner. I also live in the Southeast and you do still get some fairly cold days. I went to basic training in Fort Benning and that was during the winter and we did have a couple single digit mornings. I'm not the oil expert but I personally wouldn't use it as they say oil is cheap engines are not.

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Jerickson88

Jerickson88

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Thread Starter #3
10w30 is pretty heavy to start out with and a lot of people use it as an alternative to straight 30 weight for lawn equipment. 0w30, or a 5w30 at least start out thinner. I also live in the Southeast and you do still get some fairly cold days. I went to basic training in Fort Benning and that was during the winter and we did have a couple single digit mornings. I'm not the oil expert but I personally wouldn't use it as they say oil is cheap engines are not.

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I got ya. It may be fine for my 2004 Tahoe then. We basically sell the oil changes by the case, not quart, so we end up with 2 quarts left over a few times a month. It eventually gets recirculated thru inventory, but it is technically not there. It gets added in during annual audit if there’s a surplus.
 


TyphoonFiST

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#4
Just think when you see 0w its water thin upon start up....5w is a little thicker and 10w is even more thicker upon start up....But in the end they are all a 30weight when fully heated up and running!


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#5
I would imagine 10w30 being fine for the warmer months. Not sure how many miles you put on your car but if you did like a summer change and then a winter change with something lighter I don't see an issue. But yes 10w30 is more than fine for an old LS engine in that Tahoe.
 


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#6
I always recommend using what the manufacturer recommends. It hot weather it would be OK to use the 10W-30 but I would not in the cold weather. You may see a reduction in gas mileage by changing to 10W-30 also.
 


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Jerickson88

Jerickson88

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Thread Starter #7
Picked up Pennzoil Ultra Platinum 5w20. Service writer told me that if I drive civilized, I could push that oil to 10k, but if it were his car, he would change at 7500, and if I stayed with the MC, then to change at 5k. Parts store had a sale for $17.99 for 5 qt and STP xl filter (10k mi) but it was really like $34.95 and a $15 mail in rebate.

I may send in to Blackstone for an analysis just for fun.


I’ve always been a 3k kind of guy. Times change.
 


Intuit

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#8
Two things:

1) You don't have to go pure 10w-30 or 5w-20. You can mix weights. (avoid mixing types)
2) Ears "see" what the eyes can't. Valve train noise at cold start may mean, go thinner. (lower on the first number) Valve train noise when hot means, go thicker. (higher on second number)

Even though different oil brands have the same numbers on the bottle, they may still have different a different viscosity feel at cold/hot temps. (especially when comparing different mineral oils, or comparing mineral to synth-blend to full-synth)

If the car has been sitting for extended periods then you may get valve train noise on cold start, regardless of oil weight. The way to remediate that is to give it an extended crank time by flooring the accelerator pedal, before beginning, and during the crank. Release the pedal when ready to start. Avoid stressing the starter with stupidly long crank times. Eight seconds at a time, two cranking periods should be plenty.
 


TyphoonFiST

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#9
If its Any consolation I drove My Typhoon for one winter just for shits and rolled Mobil one 15w50 full SYN and its started right up like it was nothing in -30 below zero. I was amazed and awed at the same time. The only reason I could think of is it being SYN oil that helped its flow in cold weather! [clap]
 


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#10
I would think the thicker oil isn't very good for the turbo.
Especially when the engine is cold.

I did fill up my car with 3/4th of 10W30, to get rid of some of my oil for my old car, and added 1/4th of 0W20, just to be on the safe side.
The oil rating pretty much depends on what you throw at it. So a 25/75 ratio of 0W20 and 10W30, gives you an equal of ~7W27.
The 7 doesn't do much here in South Florida, and the W27... Supposedly the oil thins out as it gets nearer to the oil change, so I think I'm good.

With 10W30, I would just make sure you won't start the car below freezing temps too often, unless you're using an engine heater block, and I wouldn't go all out to the redline.
The oil pump has a lot more stress with W30 oil at higher RPMs, but if it handles W20 oil fine at the 6,5k redline, it will handle W30 oil fine at 4.5-5.5k RPM.
Most of the time, I don't take the car much above 5k RPM anyway, because the acceleration starts tapering off there anyway.
 


TyphoonFiST

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#11
I would think the thicker oil isn't very good for the turbo.
Especially when the engine is cold.

I did fill up my car with 3/4th of 10W30, to get rid of some of my oil for my old car, and added 1/4th of 0W20, just to be on the safe side.
The oil rating pretty much depends on what you throw at it. So a 25/75 ratio of 0W20 and 10W30, gives you an equal of ~7W27.
The 7 doesn't do much here in South Florida, and the W27... Supposedly the oil thins out as it gets nearer to the oil change, so I think I'm good.

With 10W30, I would just make sure you won't start the car below freezing temps too often, unless you're using an engine heater block, and I wouldn't go all out to the redline.
The oil pump has a lot more stress with W30 oil at higher RPMs, but if it handles W20 oil fine at the 6,5k redline, it will handle W30 oil fine at 4.5-5.5k RPM.
Most of the time, I don't take the car much above 5k RPM anyway, because the acceleration starts tapering off there anyway.
I think you should try and run your car off WD-40....Here's a link...give it a whirl...Sounds better than 7w27 oil...

https://youtu.be/moFzeZKEYSw
 


Gearbox88m

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#12
I use 5w-30 Castrol Edge gold bottle.

Never had an issue, and I am not worried I will ever have an issue due to running a thicker oil.



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M-Sport fan

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#13
The ONLY 10W-30 I personally would ever even think of using in my own FiST, and even then only in our summers here, is the Amsoil Signature Series 10W-30.

It has the absolute lowest NOACK volitility percentage levels (4.1) I have ever seen on a spec sheet for a multi-viscosity oil, so the best LSPI resistance in that respect (not sure how much calcium and magnesium, or other sulfated ash compounds are in it though [dunno], since it is NOT D1G2 rated, as are NONE of the 10W-xx oils), and the base stocks they use will ensure warm weather 'pumpability' on startup, even for a 10W, for the SUMMER season.

That being said, I will still stick with either a 5W-20 (again, the Amsoil Sig Series is looking good for this weight being a D1G2 oil with a 5.8 NOACK) in the winter, and my new go-to oil for the spring/summer, the low NOACK (6.0), D1G2 Ravenol 5W-30 DXG. [wink]
 


TyphoonFiST

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#14
The ONLY 10W-30 I personally would ever even think of using in my own FiST, and even then only in our summers here, is the Amsoil Signature Series 10W-30.

It has the absolute lowest NOACK volitility percentage levels (4.1) I have ever seen on a spec sheet for a multi-viscosity oil, so the best LSPI resistance in that respect (not sure how much calcium and magnesium, or other sulfated ash compounds are in it though [dunno], since it is NOT D1G2 rated, as are NONE of the 10W-xx oils), and the base stocks they use will ensure warm weather 'pumpability' on startup, even for a 10W, for the SUMMER season.

That being said, I will still stick with either a 5W-20 (again, the Amsoil Sig Series is looking good for this weight being a D1G2 oil with a 5.8 NOACK) in the winter, and my new go-to oil for the spring/summer, the low NOACK (6.0), D1G2 Ravenol 5W-30 DXG. [wink]
Why maKe it harder for your engine to start and flow? That's what the 10 weight does....even though it's a 30 weight in operating temperature. Plus these engines are not like your old pushrod v-6s or 8s that have looser tolerances vs. Modern tighter and closer tolerances.


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