Is it ok to switch to 10w-30?

[edwx]

My '06 4L V6 truck just turned 100K miles. I've been running the specified 5w-30 in it. Since the engine probably has a little wear on it, just thought 10w-30 might be a better fit. Thanks. Ed

 

[Jstcruz]

My '06 4L V6 truck just turned 100K miles. I've been running the specified 5w-30 in it. Since the engine probably has a little wear on it, just thought 10w-30 might be a better fit. Thanks. Ed

It really wont hurt anything, but you might want to consider running a full synthetic. and, in colder temps you want to stick with the recomended viscosity. If you are not hearing any tapping from the valvetrain I wouldnt worry about it really. A full synthetic is a good idea for any engine regardless however.

 

[bovine]

I would say do the switch to synthetic but keep the 5w-30 for where you live.

 

[edwx]

Forgot to mention that I always use full synthetic, and the truck is garaged. So a switch to 10-30 would be ok during warmer weather.

 

[jcat9]

Forgot to mention that I always use full synthetic, and the truck is garaged. So a switch to 10-30 would be ok during warmer weather.

the straight answer: It won't hurt anything, but you're not likely to gain anything from it either.

 

[The Scott]

The 0W- and 5W- are often used to increase fuel mileage as every bit helps the OEMs avoid the CAFE taxes. It seems the 0W- and 5W- are interchangeable so it would lead you to believe the 5W- and 10W- should be somewhat interchangeable.

 

[ZO6_Vette]

Just keep using 5w30 its usually better blend than 10W30, when tho oil reaches operating temp they both are at the same viscosity anyway.

 

[FIND]

Don't bother. The 5w and 10w refer to the oil's cold viscosity, and the 30 is the oils standard viscosity. At operating temperatures, a 10w30 and a 5w30 are the same viscosity. The 5w30 is less viscous in cool temperatures or at start-up though, so it is able to lube your engine better, since it flow into smaller spaces.

Besides. The amount of wear it would take before the clearances in your engine are opened up enough to need a higher viscosity oil would be the death of your engine. That's why newer engines last longer than engines from, say the 70s, when it was ok to run 40 or 50 weight oil. Those engines had huge clearances, and wore out quickly. Think about it. If you got 100k miles out of a car in the 70s or 80s, that car was a really high mileage car. Now we think nothing of cars lasting to 200k or more.

 

[katesdad1966]

The dealer changed the oil on ours when we bought it and put in 5W-20 not the specified 5W-30. I don't know what they were thinking, but I was not impressed. When I change it I will use 5W-30.

 

[edwx]

That's a bit odd. If anything they should have gone the other way and used 5w-40. Maybe you could ask them why.

 

[FIND]

Because there was a TSB to switch to 5w20 as the recommended oil. Running 5w40 in your engine is stupid. Mechanical clearances in these engines are not large enough to use a 40 weight oil. 100k miles on a modern engine is not like 100k was in the 60s, 70s and 80s when this sort of wisdom was learned. You should NOT increase the viscosity of the oil you use in modern engines as they get older.

 

[edwx]

FIND, ok then, except he said that he had 200K miles on his X, not 100. All I was suggesting was that it would have made more sense to go the other way. Plenty of guys have increased the viscosity in the past on high mileage vehicles. Not everyone is as smart as you and knows everything including all the TSBs that are out there.

 

[FordService]

Hi gang,

I recommend checking out our oil change tips here: http://owner.ford.com/servlet/ContentServer?cid=1251117147717&pagename=Owner%2FPage%2FArticleDetail&recid=1251387049862&parentheadlineimageid=1234280151966&parentrightrecid=1239636411265. That page also includes links to download free digital copies of your Owner's Manuals; that document is your best bet to get accurate information about maintenance specifications.

Thanks!

Crystal

 

[t0ked]

Going from a 30 to a 40 weight oil won't really do anything. Theoretically, a more viscous oil provides better protection, but will rob efficiency. Theoretically. Same if going from a 5W to a 10W. To experience the cold flow differences between a 5 and 10 weight oil, you need to be in some really cold temps.

A better option would be to stay at the same viscosity, 5W-30, and switch to a high mileage formula which will help "rejuvenate" the seals and can offer a bit more wear protection, if that is what you're concerned about.