My '06 without AFM usually gets better mpg than my '16 work truck with AFM. Both are 5.3's. But most of my driving is in 75 mph speed zones. So the AFM does not kick in even with cruise on. Apparently the '06 runs more efficiently on all eight than the '16 runs on all eight.
Where I notice the AFM is if AFM is engaged and I kick it in to pass. The lag is noticeable compared to non-AFM engines. Not severe, but noticeable.
Add: the '06 has about 230k miles now.
Where I notice the AFM is if AFM is engaged and I kick it in to pass. The lag is noticeable compared to non-AFM engines. Not severe, but noticeable.
Add: the '06 has about 230k miles now.
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