OK, was reading a thread earlier (THIS ONE) about taking used oil from one engine and using it in another engine to get "full use" out of the oil (although the poster did not care about the life of the engine). I read it and initially did not think much about it, but then it got me thinking (we all know what happens when we do that) 
Short version:
Is there anything really wrong with taking gently used xw-20 synthetic oil (that I have clean collected, filtered through something like a coffee filter or such) and using that as a top up oil in another vehicle that uses oil and also requires 5w-20?
Long version:
My truck ('02 F150 5.4L, 130,000 miles on motor) uses 1 qt of oil every 1500 miles (no leaks, new OEM PCV valve, no smoke noticed) and I do a 3k oil change on it because it is mostly a short tripper. I use 5w-20 conventional (Nextgen oil lately, another 1-2 changes left, some blends and HM oils from the stash in the future).
My wifes car ('12 Scion xB, 30,000 miles on the 2.4L 2AZ-FE, uses no oil) gets a change every 5000 miles or 6 months (warranty) and uses xw-20 syn (Pennzoil Platinum, QSUD, Valvoline Syn, all with Wix filters). That oil probably still has life in it, but no longer OCI till warranty over, then probably 7500 miles/annual changes.
Either way, I doubt the oil coming out of her car is in horrible shape, so I was thinking I could use the "old" synthetic oil from the Scion for top up oil for the truck (my last oil change, the Scion's oil came out a clear, dark tan color). Figure I could catch it in a clean jug (let some drain at first, then catch the middle part, let last bit drain into the pan). This would give me at least 2 qts of oil that I could "filter" with something like some coffee filters or such to use as top up oil on the truck. This used oil would only be used another 1500 miles, I think well within it's usefulness. Yes I am being cheap, or environmentally conscious depending on who you ask. Sure I could do a UOA on the Scion oil first, but that is just cost prohibitive and partially defeats the purpose of this (I am cheap).
Anyone ever done this on a regular basis, or am I just crazy to think about it?
(This next part is not a serious question)
To take it to the next step, my truck takes 6 qts, so how about using 1 qt of this "used" synthetic oil with 5 qts of new conventional or syn/blend oil in the truck at the oil change?
Short version:
Is there anything really wrong with taking gently used xw-20 synthetic oil (that I have clean collected, filtered through something like a coffee filter or such) and using that as a top up oil in another vehicle that uses oil and also requires 5w-20?
Long version:
My truck ('02 F150 5.4L, 130,000 miles on motor) uses 1 qt of oil every 1500 miles (no leaks, new OEM PCV valve, no smoke noticed) and I do a 3k oil change on it because it is mostly a short tripper. I use 5w-20 conventional (Nextgen oil lately, another 1-2 changes left, some blends and HM oils from the stash in the future).
My wifes car ('12 Scion xB, 30,000 miles on the 2.4L 2AZ-FE, uses no oil) gets a change every 5000 miles or 6 months (warranty) and uses xw-20 syn (Pennzoil Platinum, QSUD, Valvoline Syn, all with Wix filters). That oil probably still has life in it, but no longer OCI till warranty over, then probably 7500 miles/annual changes.
Either way, I doubt the oil coming out of her car is in horrible shape, so I was thinking I could use the "old" synthetic oil from the Scion for top up oil for the truck (my last oil change, the Scion's oil came out a clear, dark tan color). Figure I could catch it in a clean jug (let some drain at first, then catch the middle part, let last bit drain into the pan). This would give me at least 2 qts of oil that I could "filter" with something like some coffee filters or such to use as top up oil on the truck. This used oil would only be used another 1500 miles, I think well within it's usefulness. Yes I am being cheap, or environmentally conscious depending on who you ask. Sure I could do a UOA on the Scion oil first, but that is just cost prohibitive and partially defeats the purpose of this (I am cheap).
Anyone ever done this on a regular basis, or am I just crazy to think about it?
(This next part is not a serious question)
To take it to the next step, my truck takes 6 qts, so how about using 1 qt of this "used" synthetic oil with 5 qts of new conventional or syn/blend oil in the truck at the oil change?
