How to fatten up M1 5w30 in warm weather?

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Aug 14, 2003
Kingsport, TN
Greetings, Since the M1 5w30 tends to run a little on the thin side of SAE 30. I was thinking of adding 1 quart of the 15-50 grade to 5 qts of the 5-30 for my 5.3l LS1 in the warmer months. Any suggestions? The 5W-40 SUV stuff might do the trick as well. Thanks, EBC
I have done it for years. Others have also. It's a fine Idea. Even Mobil will tell you that it can be done-but of course they can't recommend it. A 25% solution of the 15W stuff gets you high on the 30 wt. side. [Smile]
You can also add the Schaeffers #132 additive with Moly and this will perfrom the function. Or the Brew with a 3:1 rario of the #132 and Lube Control.
hmmm ... I'd just forget about the M1 and put some GC, Amosoil 5W-30, 10W-30 or 10W-40 in the summer in there and not worry about thin M1.
ebc, I'd get some Mobil, Delvac 1, 5w-40 and use that - it's easily the best fully formulated oil they make. The Redline 5w-30 or 10w-30 would also be excellent. Redline has a much better HT/HS viscosity, so there is no need to go up a grade with this stuff .... Tooslick Dixie Synthetics
Add an oil cooler with a thermostat. This will fatten the oil up. And, it won't affect winter visc.
ebc if you want thicker oil why not just buy thicker oil. Mobil-1 has thickened up it's 10W30. Have you considered the 15W50? Tooslicks recomendation of Delvac-1 is hard to go wrong with as well.
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