Mixing oils= 5w20 with 10w-30

[rclint]

I found a nice deal on Havoline Deposit Shield, and bought a couple of oil changes in 5w-20, they had plenty more 10w-30 and even more 10w-40 left, all in Havoline Deposit Shield. My 02 Honda Accord calls for 5w-20, I have no problem running 5w-30, however 10w-40 is stretching it some on this deal in my mind.

So my question is, would you mix the 5w-20 with the 10w-30, or just wait until summer then run the 10w-30, running the 5w-20 in the winter ? I have along commute to work, around 40 miles each way with high speed interstate driving. I have run 10w-30 before with no problems, however it does seem the engine my is smoother at colder temps with the 5w-20 compared to 10w-30 (maybe all in my head)... anyway I just wanted to hear some comments before I buy out the rest of the 10w-30, and just for grins what say you about the 10w-40 ?

I have never been one for mixing oils, nothing against it, it just never floated my boat, however in the situation mixing in the exact same brand may not be to bad of a blasphemy

 

[ARCOgraphite]

I wouldnt mix, the 5W-20 appear to have a beefed up chemistry that the 10w dont. I think this mixing thing should be left to the early SAE monogrades. If you saw the complexity of the oil formulation for a modern GF4 multigrade you wouldnt dare disturb this delicate balance.

 

[ARCOgraphite]

read this:

http://www.freepatentsonline.com/4402841.html?query=synthetic+motor+oil&stemming=on

 

[addyguy]

I'd buy all the 10W-30 I could, after getting the 5W-20. DS 30-weights are very thin (9.7cst), so they are almost a 20-weight. It will work great in your car in Georgia year-round.

If the deal is really, REALLY good, the I'd also buy all the 10W-40 I could stash/stand having - DS oils are really good in all grades, and in the summer, the 10W-40 would work well but cost you a bit of MPG's.

 

[CharBaby]

I would stay with the thinner oil in the winter and the heavier oil in the summer balancing out your oil purchace somehow. Being in GA, I don't know how cold it get there during the winter months. Even though mixing may not be the optimum thing to do, I've been doing it for over 37 years(not every single OCI, but often). Years ago, I mixed because I would use anything in my beaters due to lack of money. You wouldn't beleive the oil I have mixed for an OCI(5 different brands each being a different grade). Today I mix because I have 60, 70 or 80 qts of oil(dino & syn) from sales, rebates, closeouts, FAR, and because I like to add 2qts of syn to 3qts of dino. Often mixing 5W20 w/ 5W30 for the winter and 5W30 w/ 10W30 for the summer. Depending on what oils I have in my stash at the time is what I decide to mix as long as it's somewhat of a balance IMHO. Not trying to be a scientist or oil engineer but I've never had engine issues due to oil mixing and I've put on several hundred thousand miles on engines doing this.

 

[CharBaby]

As the matter of fact, I have put 300,000 miles or more on at least 2 engines and over 200,000 on all the rest of the vehicles. I think around 8 vehicles.

 

[rclint]

I'm really in a bad situation haha... I have a big enoug oil stash as it is, however the Havoline DS is $1.49 a quart, and to top that off, they have just as much Chevron Supreme in 10w-30 same price. They probably have 40 quarts of 10w-30. Also have a lot of Havoline DS high mileage, I have not heard anything on the Havoline DS high mileage.... which would be around $2.25 a quart.

 

[pbm]

I use 5w20 in winter and 10w30 in summer in my 01' Accord mainly because I have a lot of 10w30 stashed. I've never had a problem but I do feel the engine revs a bit freer with the 5w20.

PS: I'd buy up the Chevron 10w30 at that price. It's a great oil IMO.

 

[addyguy]

Yeah, grab at least all the 10W-30 you can of both Havoline DS and Chevron - same oil basically.

That is a good price on a high-quality oil!