m1 0w40 to m1 0w20ep switch in 99 4.6 ford

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Originally Posted By: merconvvv
Oh i forgot to mention that cat converter is more alive with 0w20.

Originally Posted By: micmac
I have had good luck blending 4:5 TGMO 0w20:Mobil 1 0w40 FS. This will give you a nice 0w30 with a much higher VI than Mobil 1 AFE 0W30 and a nice high TBN and SAPS for extended drain intervals. Credit to Caterham for the recipe.

It will give you something, as Shannow noted, with a 30 rating when hot. You have no idea what the CCS/MRV performance is, but given the group III content of TGMO (it is entirely group III based) and Mobil 1 0w-40 FS being GTL-based, the PPD's are being diluted in a base that doesn't require PPD's, reducing their effectiveness for the base that does require them (group III). Ergo, you have no real idea what the W rating for the finished mix is going to be nor do you really know what the VI is going to be either, given you are again diluting the VII's from various base mixtures with each other, which completely skews the treatment mix and results in ?????

Ultimately, without putting the "mix" through the requisite testing, the best that can be claimed is that it will not cause damage. It cannot claim superior performance by any metric without being properly vetted through the protocols the mixed constituents were subjected to during their individual developments and approvals.

It is incredibly naive (or pompous depending on how the claim is being made) to believe one can create a superior end product by mixing two fully formulated lubricants together. The chemistry involved essentially prohibits this. Each product is a rigorously tested compromise in a huge host of areas, including cost, in order to meet specific performance criteria. A Euro 0w-40 and an ILSAC 0w-20 are worlds apart in terms of the OEM test protocols just to scratch the surface of those development processes. Ergo, mixing two chemical compromises together results in yet another compromise, but one which has not been tested for the applications that either individual product has. You create what is essentially an unknown with the only guarantee being that it won't separate and that whatever the resulting chemistry is, it is no longer optimal.

I'm not a fan.
Update: I drained out 2 quarts of 0w20 ep so now the 1999 expedition has brew X:
4 quarts of 0w20ep + 2.5 quarts of m1 15w50. I have mostly concluded that there are no noticeable significant differences in noise levels and performance with any of the oils listed below! My expedition now has had in its lifetime

100C. 40C. 150C. Pour point
MC 5w30. Factory fill so dont know
M1 5w30. 11.0. 61.7. 3.1. -42c
M1 0w30afe. 10.9. 62.9. 3.0. -50c
M1 0w40. 12.9. 70.8. 3.6. -54c
M1 0w20ep. 8.6. 44.9. 2.7. -54c
Brew X. 12.2. 75.2. 3.4. -48c

I prefer little heavier than 0w20 for the 1999 expy since it was designed for 30 weigjt to start with and many people using quality oil with good maintenance have had excellent results im their modular including me. Lousy oil, lousy cold weather and lousy care would result in engine wear/failure in 1999 era modular (not with a quailty 5w30). My .02. (or my fuel savings lost).

For 1999 era modular, too low viscosity at 100c might yield too low oil pressure at idle concerns me enough to stick with oils close to or above 30 weight. The timing chain tensioner relies on oil pressure to keep the chains from slacking. Perhaps someone can provide more info on these matters. I am here to learn.

In some cases brewing can yields interesting results.
Consider a brew Y consisting of:
5 quarts of m1 0w20ep + 1 quart of m1 15w50.

100C. 40C. 150C. Pour point
M1 5w30ep 10.6. 59.8 3.0. -40c
M1 10w30ep. 10.2. 63.7. 3.1. -39c
Brew Y. 10.2. 58.3. 3.0. -51c
M1 0w30afe. 10.9. 62.9. 3.0. -50c

I am assuming "linearity" in calculating brew y numbers (otherwise one could not top off with different oils and even manufacturers would have a tough time designing oils i think). Brew Y has more zinc and phosphorous, less magnesium (than 5W30ep and 10w30ep) (ca:mg ratio should be ok). Brew Y is close to being a 0w30ep.
Originally Posted By: merconvvv
Ya the cat conv has not fallen off bro
Thanks for asking.

No, no. You were describing how it was "more alive" with the 0W-20, and I wanted to know it's aliveness with all the changes you made.
From machinerylubrication.com
How Oil Consumption Influences Tailpipe Emissions and Health

As engines age and wear, they become greater consumers of crankcase oil. Solid contaminants combined with soot and other oil suspensions influence engine wear, deposits and oil economy (oil consumption rate). When oil is consumed, it enters the combustion chamber, burns with the fuel and is pushed out with exhaust gases as particles and volatile hydrocarbons.
With great reservation i switched the expedition from mobil 1 to QSUD 10w30 and am pleasantly surprised. (Long time m1 user). Oil consumption dropped dramatically with QSUD 10w30. Did my usual 800 mile hwy run at [censored] speeds and oil level only dropped one sixth of a quart. Happy that expedition is still in good shape. M1 gets some credit too. But i will stay with qsud for now !
If your nearly 20 year old truck burns a quart of oil every 700 miles, it does not matter what you use. You'd have added 10 quarts in 7500 miles in addition to your 6.5Q initial fill. I'd just go with Moto semi-syn unless you get a similar $3/Q deal from M1 (after rebate).
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