Wow! Gas Mileage Hit Changing from 10w-30 to 10w-40
#1
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Trying out conventional 10w-40 after running synthetic 10w-30 and am seeing a drop in mpg. Was aware of the hit when running 10w-60 in my 2000 M5 vs 5w-30, though I chose to continue to run the heavier stuff. Wasn't expecting it here.
Anyone know if switching back to synthetic, but sticking with 10w-40 will improve fuel efficiency?
And yes, I know 'fuel efficiency' is an oxymoron in DII land.
Thanks,
Dave
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04 Discovery SE7
78k Miles
Anyone know if switching back to synthetic, but sticking with 10w-40 will improve fuel efficiency?
And yes, I know 'fuel efficiency' is an oxymoron in DII land.
Thanks,
Dave
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04 Discovery SE7
78k Miles
#3
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Thanks for the reply, Spike. You know, I also usually run Shell, but had to fill up on Chevron, so my results could be attributed to a number of factors, as well as different driving patterns.
As for mileage, I get ~16mpg highway only (fully loaded up & down mountain runs...people, gear, etc), and 12.5-13.5 local (combination hwy and city).
I'll wait until I can fill up with Shell and see where I am mileage wise 20-22 gallons in.
Thanks,
Dave
As for mileage, I get ~16mpg highway only (fully loaded up & down mountain runs...people, gear, etc), and 12.5-13.5 local (combination hwy and city).
I'll wait until I can fill up with Shell and see where I am mileage wise 20-22 gallons in.
Thanks,
Dave
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I use 5w40 year round. Switching from 10w40 to 10w30 in the winter really will accomplish little even thought the 10w30 is a bit thinner at start up. Change down to a 5w40 or a 0w40 and you are getting somewhere.