Should I switch back to 10w30 for winter months?

[GrandMarq90]

My 90GM with 75k came with 10w30 when I purchased it last March. When I did the oil change I put in 10w40 and have used that ever since.

Now that winter is coming up should I go back to the 10w30? I would think I don't have to since they are both 10w, only the operating temp # went up, so I would think the 40 weight would be better?

The car runs great, quiet and gets good gas mileage with the 10w40. I just want confirmation that it's cool to use that when the temps here can get to 0 degrees or below in the winter months here in NY.

[Lincolnmania]

i would stick with 10w30 in the winter and 10w40 in the summer........super thin oil wont do the oil pressure any good in an older engine

[Archangel]

I just changed my oil last weekend, used the synthetic 5W30 by Mobil 1 that she's been running on for the last half year (mostly freeway miles) - is it too thin for the winter? Here in Michign it gets pretty darn cold (last time there was a whole week of -18C) and I run a flex fan, but I usually do give the engine a 5-10 minute warmup at idle before I take off.

[Ape]

mmm Winterpeg MB, Canada :(

[RustyShackelford]

Slight thread-jack...... what about using the Lucas Oil Treatment in the winter? Will it thicken it up too much.? It can get pretty derned cold here in Indy.

[Chachi]

i use 20w50 year round in ny

[Lincolnmania]

i run lucas and 10w40 year round in my dads sundance.........starts every time no matter how cold it is

[gadget73]

10W40 won't hurt anything probably, but if you hear it tapping for a few seconds when it fires up in the morning when cold, try switching to 10w30. My truck really likes it's thin oil, and will tick and tap annoyingly unless I feed it 5w30.

[RustyShackelford]

5W30 is what the norm is around here... which is why I was wonderingbout the lucas. Hell Ill use lucas and 530. maybe give castrol gtx a go, too.

[monterey1962]

For some reason I forgot, which one is the thinner one, 10-W30 or 10-W40? I run Cenex Auto Gold 10-W30 year round. Going to add a bottle of Lucas on the next change to quiet her down a bit.

[Pimp Hard Or Bust]

in my camaro i run 5w30 in the summer and in te cold i add a synthetic bottle of 0w30 to thin it up even more.

ill do the same to my towncar after the engine is in and broke in

[GrandMarq90]

Thanks guys, I'm gonna go back to 10w30 for the winter months.

[Blaze86Vic]

I just put 10W 30 in my Vic today.

[TommyN]

I run synthetic oil in the cars I drive in the winter. If you ever change your oil on a winter day when it it below freezing, you can definitely tell the difference between synthetic oil and regular oil. The synthetic oil still pours like water whereas the dino oil pours like molasses. I figure the oil pump has to work much less to circulate that synthetic oil on a cold day than it would with dino oil.

Tom

[Blaze86Vic]

True, untill you have been running for 3 minutes. By them the oil is well above room temp, and at it's normal opperating viscosity.

[GrandMarq90]

I picked up a Motorcraft filter today( only use that filter) and a 5qt Jug of Castrol Syntec blend 10w30. I'm due for my change next weekend so I will do it then.

[Pimp Hard Or Bust]

True, untill you have been running for 3 minutes. By them the oil is well above room temp, and at it's normal opperating viscosity.

its in that 3 minutes that engine wear mostly occours

[Blaze86Vic]

Unless you let the car warm up. Which in the winter becomes much more critical.

[gadget73]

Unless you let the car warm up. Which in the winter becomes much more critical.

That first few seconds where its not pumping oil, whether its just sitting at an idle or not creates a lot of wear. Personally I'm a fan of running the thinnest oil you can get away with that is reccomended by the manufacturer. For a 302, they pretty much harp 10w30 and 10w40 in the manual for most all weather conditions. I just run 10w30 because its slightly thinner, and my engine doesn't use or leak oil. If it did, I'd run 10w40 to see if it helped. My truck runs 5w30, which is the reccomended oil for it. It also keeps the lifters from ticking in the winter, so I figure it must be doing something good for it. Valvetrain clatter on startup is a sign of running with poor lubrication. Anything I can to thats simple to keep that clattering and ticking from happening is worth it, even if it does mean running salad oil in the motor.

If you ever want to learn way more about engine oil than most people want to know, have a look at this article written by a guy over on LoL. http://www.lincolnsonline.com/article105.html

[RustyShackelford]

If you ever want to learn way more about engine oil than most people want to know, have a look at this article written by a guy over on LoL. http://www.lincolnsonline.com/article105.html

good info, there!! :clap:

[Mercracer]

i would stick with 10w30 in the winter and 10w40 in the summer........super thin oil wont do the oil pressure any good in an older engine

Oil film thickness is what lubricates, not oil pressure. In a higher RPM engine you need more oil flow to maintain the same film thickness as a lower RPM engine does. Higher RPM engines also have more clearance built in to the crank/rod bearings therefore need more flow.
5W30 is not super thin oil and is fine in older engines for the winter. If you are loosing oil pressure, you need more oil flow not thicker oil which will produce less flow and increase oil pressure before the bearings due to resistance to flow.