What would you recommend to raise VRP oil viscosity?

[Josh.ely]

I went a bit overboard and purchased 48qts (8 cases of 6qts) of 5w20 to use in my 2016 F150 5.0l and my father in laws 2017 F150 5.0l. 5w20 is the recommended weight. After a lot of reading it appears that a lot of F150 5.0l owners are getting better results with 5w30 and 10w30 motor oils. Helping with valve train noise and retaining better viscosity levels between the 5k-8k mile OCI's. People are saying the 5w20 losses viscosity, especially when higher sustain engine temperatures are involved.
Which got me to thinking about trying to up the viscosity of my VRP 5w20 to say 5w30.
Then today my Father in law bought a 2018 Expedition Max with 3.5L EB engine that is recommended to use 5w30.
Now really wanting me to bump my 5w20 to at least something around 5w30.

What product would be recommended to add with my 5w20 to get closer to 5w30?

I'm great at math so figuring out ratios is easy but knowing what product to use is not something I want to guess at.
I've ready that mixing different oils can actually be more harmful due to competing or incompatible additives.

 

[samven]

There is no way to predict exactly what you will get because of the differences in the additive pack even in the same line, but the safest route might be to stick with VRP line and mix 50/50 with their 10w40.

 

[Olds394]

I would add one quart of VRP 5w-30 each oci, and top off with VRP 5w-30.

 

[FowVay]

The quickest and simplest way to increase an oil's viscosity is to simply measure it at a few degrees cooler. It's really that easy.

 

[dnewton3]

What would I recommend to change the vis? Nothing. Not a darn thing ...

Do NOT add anything to the oil. You're not going to be able to assure yourself of the desired vis shift unless you run some VOAs pre and post, and by that time, you've spent more money on testing than it would be worth. Even if you add VM, you're altering not only the ratio of the vis, but also all the other additives because you're not keeping them proportional in the overall mixture. Simply put, resist the temptation to play garage chemist.

Rather, sell the oil you don't want to someone who can use it, and then buy some VRP in the desired 5w-30 viscosity. Or, return it for credit and get the other oil.

 

[CharBaby]

Can you return some of the VRP 5W20 and buy/exchange for some 5W30?
I wouldn’t mess with the VRP. Just buy the 5W30 for his application.

 

[melk]

I assume the cases are unopened. Should be able to return them?

 

[kschachn]

I’m not sure what “better results” you saw but if a 20-grade is recommended for that engine then just use it. Decrease the OCI if you wish, but if it were me I’d just use it. Once it’s gone then start buying a 30-grade or whatever you want.