Mobil One 0W-30
has a 2% promise on the back label now.

Assuming that ExxonMobil is telling the truth
there might be a 4% MPG difference
between the ''worst" conventional oil
and this low friction viscosity of Mobil One.

2% of 20 MPG at a steady highway cruise
would be 0.4

You can get most of the benefit
of low viscosity lube oil
by switching out your thermostat
to one with a higher temperature rating.

The hotter the lube oil on the bore walls of the cylinder
the lower the 'real world' viscosity
and the lower the friction on the piston rings.

The old small block LA Chrysler V8s used to be 180.
Then the Magnum series V8s went to 195
Then the Hemi V8s went to 203

This same trend can be seen with all the automakers world wide.

 

i wouldn't call it stuck on either, i think we just got one or the other. i got amsoil cuz for $10 i get about 20% off with their preffered customer thing. when you're buying oil for an engine, a transfer case, two diffs, filters, and some stuff for a friend, it pays off.

do yourself a favor matt, keep checking you engine for sludge. mmstar had sludge when he switched from dino to RP, almost cost him his truck, but he caught it in time. look up his thread, it's got a lot of useful info in ther eabout sludge, how to catch and prevent it, and how to fix it. i think it would be worth your time.

it would also be harder for the oil to make a film on the bore wall. if you're wanting to do that, leave the thermostat alone and just throw some 0-20 in there. it'll help your mpg, don't know if i'd recommend it though. it'll also increase your oil consumption if your truck likes burning oil.

 

it is the 'film strength' ability of the oil
rather than the viscosity (which is related to friction)
and supposedly
Mobil One Synthetic has
extremely high film strength

 

feejay, i would say matts truck is too new to create any devastating sludge like mine did. but its always good to be safe rather than sorry. if any sludge was made, id bet after putting synthetic in, and changing the first oil change, most of the sludge would come out in the change. what i do recomend is that you change your synthetic in 3,000 miles the first time rather than an extended period of time

 

yea man. i hope it isn't there. but it would suck if it was and he didn't catch it. i just thought about it when he said it came out burnt.

Hank, we're talking about changing temperature or viscosity within a brand. heating the oil up will make it flow easier by decreasing viscosity. viscosity is determined by how easily oil flows, basically the friction within the oil.

all other things equal, changing temp will have a similar effect as changing viscosity. viscosity is easier.

 

I didn't notice any difference. Went to synth after the first 3k oil change. Good luck.

Rick

 

let me know if changing from mobil one to rp was worth the extra $2 a quart! i have been thinking about doing it but i put a descent amount of miles on my truck during winter and really didnt want to spend the extra $2 a quart. i might have a job closer to home now so i wont have to put so many miles on my truck so it wont be that big of a deal. so just let me know if it is worth it please.

 

might seem like i'm cheering for team amsoil, but if you become a preffered customer ($10), most everything is %20 off, and then doesn't cost any more than M1 if you have a distributor nearby you can pick up from.

 

How many miles did you have when you switched over?


BTW I like Royal Purple I use it in all of our vehicles.