A couple of recent threads sparked my interest and got me wondering:

Can I save money by using synthetic oil?

So I did up a simple spreadsheet to see how much I would save (or lose) and decided to share. I think that I covered all the parameters involved. If I left something out, let me know so that I can correct it.

Enjoy:)

With the intervals shown, you could also add in the costs associated with either paying someone to change it for you or the time doing it yourself as well as the waste oil and filters that you have to dispose of. Those costs alone can bring the savings much higher overall, especially with the 30K miles intervals with the synthetic, but to be completely honest about that mileage interval, although I do run longer intervals, I still perform UOA when I get to different mileage levels depending on the most recent driving I have done. For example, when I am done hauling Christmas trees and have run the truck hard, I personally like to know nothing is happening inside the engine I need to know about, but I have also not yet had to change the oil due to issues with it holding up to the abuse or breaking down.

I agree with what is said above- however it is a nice piece of work!!!! I believe the price on the synthetic may be a little high (I guess depending on what brands you found)????

The figures that are in the spreadsheet are not what I used to figure my personal cost/savings. I already found that it would not be cost effective for me to go to Synthetics. I used nice round even numbers to double check the accuracy of the equations before I uploaded it.

I posted the spreadsheet so that others could use it as a tool to make an informed decision. It can be completely customized to the current market prices, desired OCI's, filter price, filter change intervals, and UOA intervals if desired.

Chris, thanks for the suggestions. I'll try to work them in. Current "to-do" list:

Disposal fee's
Advanced UOA formula (ie: UOA ever 5K after the initial 15k)
Fix "Filter Cost" to round up to the next whole filter (ie: 25k OCI w/ Filter change every 10k = 2.5 filters ---> 3 filters)But, I have to brush-up on my Excel skills before it goes any further.

That is an excellent tool! Many thanks. It's not anything difficult, and we've all done it many times on paper, but it's nice to have in electronic form! It really simplifies the process.

What needs to be acknowledged, and CAN be accounted for with this good design, is that you have to make sure to tailor the entire program to your own criteria. ALL inputs have to be adjusted for the data to work correctly. As programmed, it's easy to do!

I only drive 6k miles a year in my truck, but for the GM warranty to be valid, I have to OCI once a year. When you figure that in, it blows the cost of synthetic sky-high! Most Dmax trucks can easily go 10k miles on dino oil, per UOA evidence. This is the perfect tool to show how synthetics can be great savigns tools IF the OCI is extended. And if not, they are a total waste.

Further, the actual OCI duration will need to be fit into each individual plan, but it's very well accounted for with the cost of UOAs included!

Very well done! My compliments. May we share this with others, Rader?

This is roughly what it would be for my situation. I didn't figure in UOA's since it would be a wash between dino and syn.

Thanks Rader!

Interesting indeed thanks for sharing this tool.

May we share this with others, Rader?

Absolutly. Feel free to share and/or modify in any way you like.