Viscosity Change

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Sep 24, 2020 | 02:04 PM

jimgnj

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5th Wheeling

Joined: Mar 2020

Posts: 49

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Viscosity Change

At 265,000 miles on the 4.2 I've started using 10w/30 in place of the specified 5w/20 due to consumption of about a quart every 1,000 miles. What are you folks doing?

Sep 24, 2020 | 09:55 PM

steve(ill)

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Joined: Jul 2005

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10w 30 will not hurt.... did it change the consumption ?

Sep 24, 2020 | 10:32 PM

Ryan P

New User

Joined: Sep 2020

Posts: 4

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I have a 5.4 with 275,000 and have gone back to 5W-30 from 5W-20. It seemed to help but I didn't really pay attention to how often I was adding oil before and after.

Sep 24, 2020 | 11:49 PM

Johnny Paycheck

Fleet Mechanic

Joined: Jul 2019

Posts: 1,323

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I’ve used 10-30 and 10-40 at various times. No issues. Got 10-30 for the last oil change and the manager thought I was crazy for some reason because of the 5-20 on the cap. Oh well.

I’ve got 276,000 miles and a leaking rear main seal or whatever is left of it. Oil consumption is about what yours is at. Won’t bother with it until another engine goes in.