Any problems using 15w-40 in a car?

[JCCADILLACMOBILE]

Originally Posted By: hominid7
For a bit of interesting trivia, Pennzoil Long Life 15w40 actually has a lower pour point than Pennzoil conventional 10w30.



Probably sue to the base Oils. The Higher Non-W happens when heat "Avtivates" the Viscosity Improvers.

 

[heypete]

Originally Posted By: JCCADILLACMOBILE
Originally Posted By: FusilliJerry82
What about mixing 50/50 with 5w-20.


1) 50s50 isnt a grade.. Stright 50 is made.

2) That would be weird. Just use the median of the two.. 10w30.

3) Seems even 5w30 WOULD be OK in Summer Miami.

I think he meant "Mix 1 part Rotella with 1 part 5W-20", for a 50/50 mixture of the two.

I agree with #3: if 10w30 is suitable for hot climates, certainly 5w30 or 0w30 would be suitable for those same climates, as they have the same viscosity at operating temperature.

 

[countryboy9799]

Thanks for all the info. So something like rotella or delo is going to be a better cleaning oil than synthetics?

 

[JCCADILLACMOBILE]

Originally Posted By: countryboy9799
Thanks for all the info. So something like rotella or delo is going to be a better cleaning oil than synthetics?


Good Question! However, i thougth Pennzoil Ultra was the best "Cleaning Oil" EVER (If Pennzoil Platinum cleans out up to 46% of Sludge on first Oil Change, obviously in a controlled Engine..) ... not sure how Rotella or DELO could beat that.. even though people have sworn by the Diesel Oils.

Even Mobil 1 will "Clean" well, as will most any Synthetic, IIRC. Still good question...

 

[fdcg27]

No problems in the warmer months.
I used Tection 15w40 (dirt cheap on clearnace) in both my Aerostar and my '97 Accord.
I used clearance M1 15W-50 in my '99 Accord.
No problem at all with these oils.
Any loss in fuel economy is too small to notice.
Maybe the Australian viscosity recs are right after all.

 

[JT1]

15w40 is what 3 maybe 4 cst thicker than a 5w30 at operating temps? I don't see the big deal here as far as fuel economy is concerned.

Now using it in the dead of winter(gets cold here in MI), I'm sure there are some risks associated with that. In the spring/summertime however I can't see any negative effects as because it will be thinner at 45f than a 5w30 would in typical winter temps of 10f.

 

[ARCOgraphite]

Originally Posted By: heypete


I agree with #3: if 10w30 is suitable for hot climates, certainly 5w30 or 0w30 would be suitable for those same climates, as they have the same viscosity at operating temperature.
Viscometrics dont tell the whole picture on how an oil will react in the engine - especially multigrades. Think a conventional 5w30 is typically a 6>7 SAE base oil with VII whereas a SAE 30 is - you guessed it an SAE 30 - all oil. Run both in a hot climate and tell me they are the same in the engine. Hot run VII's tend to be very "gummy" running and the SAE is very "slickery" - given that it's OIL and not loaded with coverted EPDM rubber - as used in basic 5w30 and 10w-40. ALL oil blends are different and do different things in different engines using different filters.

 

[ENGINEER60]

I have a 1.9L 4 banger with 300,000 miles on it so it's tolerances are such that 10w30 is just too thin for summer
use.

I use 10w30 in the winter for better starts, but as soon as temps rise above freezing, I start using 15w40.

Diesel oils have more detergent and dispersants so it keeps the engine cleaner and the engine maintains better oil pressure while idling in hot weather.

It's just the ticket for a high mileage engine like mine

 

[daman]

Originally Posted By: ENGINEER60
I have a 1.9L 4 banger with 300,000 miles on it so it's tolerances are such that 10w30 is just too thin for summer
use.

I use 10w30 in the winter for better starts, but as soon as temps rise above freezing, I start using 15w40.

Diesel oils have more detergent and dispersants so it keeps the engine cleaner and the engine maintains better oil pressure while idling in hot weather.

It's just the ticket for a high mileage engine like mine

Why? do you experience a tick or low oil pressure?? i cant see a 30w being to "thin" in that aplication, my brother has a grand am with 342,000 miles and uses 0w30,,unless your problem is just a ford thing.

 

[Akiba]

"I use 10w30 in the winter for better starts, but as soon as temps rise above freezing, I start using 15w40."

i really don't see anything wrong with useing 15w40 even if it's say 20F out side. well 20F isn't consider cold for most dino oils i don't think. either way i say this because one winter morning a good 10 years or more back i change the oil in my old ford tempo. my brother told me the 15w40 would be to thick for the engine but honestly i had the car only to beat around with so could care less. to see if the car would pump a jug of 15w40 that's been out in the freezing temps i pour it in, took off my valve cover, turn the engine, and instantly watch oil spray all over the place. besides i like using rotella 15w40 in that car.

in other words i doubt it would be a issue but don't take my word for it just in case your stuff blows ... lol.

 

[countryboy9799]

I was thinking too that with the miles I have on it that would make a difference too. The quad 4 has 203,000 and the 3100 has 125,000 miles on it so its not like they are brand new. I will be changing it shortly as its warming up.