MrMonte
Full Access Member
- Joined
- Jun 23, 2022
- Posts
- 203
- Reaction score
- 505
I turned off the AFM via a tune on my 2018 Yukon Denali, use Mobil 1 oil & OEM filter every 5-6K miles. I still had an AFM lifter fail at 82K miles then did a cam/lifter upgrade deleting the AFM system. Now at 115K miles and enjoying the extra power & better mileage. I did a 2k mile road trip last month and averaged 21.2mpg with avg speed of 79mph. I'm running 305 summer tires that are 33" tall which did hurt my mileage some. My speedometer has been adjusted to match a GPS.
My son had an AFM lifter fail at 115K on his 2015 Yukon Denali.
My son had an AFM lifter fail at 115K on his 2015 Yukon Denali.
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