lds additive and octane?
#1
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i just changed the rear diff fluid with mobil 1 75-140w and i didn't check ahead of time and added 7oz of the lds additive. will this hurt anything? also, i've read here about running 89 octane. my problem is that all the 89 in my area has 10% ethanol. is this ok, or should i run 87 with no ethanol? thanks!
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Are you asking because the Mobil product already has the additive in it? If so, it's not a problem, I have to add 4 oz. of additive to my Grand Cherokee rear diff just to get it to make sharp turns without chirping at me even though my RP already has it in. Next time though, try it without adding extra and if you get a little chirping or ratcheting on turns, add a little until it stops. Too much can make the properties of the oil break down a little faster, but nothing catastrophic from your putting a little more in there than what you needed.
As far as the gas goes, use the 89, even though it has ethanol although it'd be nice if you could find a place has the mid grade without it.
As far as the gas goes, use the 89, even though it has ethanol although it'd be nice if you could find a place has the mid grade without it.
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I'm not sure how it is on a stock tune, but I've calculated EVERY possible scenario with my SC tuner on my truck and the most efficient MPGs I get are with the 91 octane performance tune with 93 octane gas. Even when calculating the higher cost of premium fuel, my cost per mile is best with it.
You may pay more per fillup, but the gas mileage gains may equal you out or even have you slightly ahead of the game...
You may pay more per fillup, but the gas mileage gains may equal you out or even have you slightly ahead of the game...