Upgrading 6.7

[Toddramhemi]

I just picked up this 6.7 and the mileage is crazy good. Almost 350 miles and only a half a tank used. I here people
Wanting to improve there mileage and power in these and I’d like to explore my options. Currently living in New Mexico (finally outta of California) I’m thinking of installing at least 33’s but will my fuel mileage decrease so much that I’ll be kicking myself? Cold air intake recommendations? I would like
To keep my fuel image around the same and I would like to put larger tires on it. Any suggestions?

 

[Brandon-w]

33s are equivalent to stock tire size just wider. I run 33x12.50r20 on mine with no difference.

 

[Toddramhemi]

Thanks Brandon. This is good to know. I definitely want a wider tire. Do you have any experience with the Falcon wildpeak A/T? I’ve owned them on 1500’s that I’ve owned and there M1 series as well. What brand of tires are you currently using?

 

[Brandon-w]

I had toyo at2 extremes I'm running firestone mt2

 

[Toddramhemi]

Thanks for sharing. Those have massive cleats. I’m think I’m going to go with a less aggressive tread.

 

[Brandon-w]

Yeah the tread blocks are huge. They're not actually that loud though surprisingly.

 

[mtnrider]

33's are pretty much stock so you won't see much if any decrease in mpg as mentioned. I'm running 11.5x35's and still getting acceptable mpg for a 8000lb truck (and my style of driving).
As far as mods to get better mpg, None. Leave it alone, period. Stock Truck already has the best airflow and filtration system so just wasting money (and getting inferior filtration) by swapping it out.

The only way to improve power is to tune and delete. But that comes at a cost of no more warranty and to be honest I see a lot more people having issues after tuning then leaving it stock. Not to mention even slight increase's in HP can destroy the 68RFE transmission unless you are very careful. And even with tuning mpg gain for these late model truck will be minimal if any. If it's a 2011,12 etc you will gain some tuning those.


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