For instance I've been using Mobil 1 syn. 0W-20 but it seems real thin to me. Could I maybe use a 50-50 mix of say 0w-20 and 5w-30? Will they mix just fine or is that a huge NO NO?

 

You might be able to but I don’t know one way or the other. I would look at it as the truck is expensive and oil is cheap, even if it’s $5 a quart. $30 is very cheap peace of mind so I wouldn’t even try to mix different weights…

 

No problem, mix away! You just end up with a mix that has a average viscosity. Quick search on Google came up with this link

 

You can mix any motor oil with any motor oil. You can mix different weights together. You can mix different brands. You can mix dino with synthetic. Nothing bad as far as some wierd chemical reaction will occur.
You can whip up any sort of oil ****tail that you feel gives you peice of mind. (but not thicker than 30wt for modular motors)

I think most use 5/30, except for the paranoid ones that think using anything but what Ford says will void warranty.

 

I only mix oils for cars I hate.

 

Several years ago, I read that you should not mix different grades of multi-weight oils. The article stated that mixing single-weight oils of different viscosities is OK, but mixing different multi-viscosity oils (e.g.: mixing 0W-20 with 5W-30) can cause lubrication problems.

As I said, this was several years ago (maybe five or so), but I've read nothing since that would contradict the article.

 

i use the best money can buy 5-20 motorcraft and motorcraft filters that gives me peace of mine no worrys with 500 + plus horsepower lightning

 

Although it can be done, I would advise against mixing different oils of different manufacturers or even different types between the same brand. The additive packages are all different and you won't get the maximum benefit of the oil. Oil is fairly inexpensive and I wouldn't do it unless it was an emergency to bring the oil back up tp level. If you want to viscosity blend, it would be best to stay within the same brand and same type, but even then the polymers are different for different viscosity oils.

 

You do realize that Ford doesn't make Motocraft oil and it's only an oil that they put out for bid don't you? Last I heard it was being made by Conoco, but this can change as contracts run out. Ford submits a minimum spec for bidding purposes and different oil manufacturers bid for the business. Typically the contracts are for 3 to 5 years.

 

you would think they would put it on the oil container who iy wasmade by

 

I been using Castro 40 HD motor oil for several months and have never had any problems. To my liking the syn oil was too thin.


My Mods on 02 L with 50K miles:
4 lb lower
2 lb upper
ported eaton
diablo chip tuned by JLP
heat exhanger
long tube headers
with full exhaust w/o cats
sb/tb
cold air intake
95 mm mass air meter


My bone stock bottom end is still holding on strong... and I have a really heavy foot. I blow up my tranny first rather then my engine And I would change my tranny's oil every 15 k?

 

Thanks for all the info. I noticed a couple people advising me that oil is cheap and to buy more rather than chance it. I just wanted to clarify, this has nothing to do with me trying to save a penny. I am just trying to use a little thicker oil, 0W-20 seems real thin. I thought (if it was koser) that 50-50 mix of Mobil 1 0w-20 and Mobil 1 5W-30 would be about what I'm looking for. If You guys gave me the green light I would completly drain the oil that was changed just yesterday and put in a mix, so it's not about me being cheap.

Another question though: after using a particular weight for some time is it safe to just switch to another, or does the motor "get used" to what has been in it for a while?

 

NOT being a smartass here, but what is the point???

why not just pick a weight and use it?

your "special blend" of 5W25 oil isn't going to protect any better or perform any better than the 0/20 or the 5/30.

go the the Mobil1 website, or even better give them a call. while the oils are certainly compatible, they didn't spend the time and money engineering each different weight of oils because they want you to play witches brew mixing them together randomly. as was said above, each oil has different additive packages and amounts of base stock or whatever they call it.

you are making a simple oil change complicated.

I say use the 5W30 or 10W30. anythingW20 is too thin anyway, and they only use it in the first place for fuel economy CAFE standards.

just my .02

good luck