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[Encycloman]

Posted some pics. Sure could use some advice on whether to keep the stock wheels and tires - or shoot for larger wheels and tires to boost the rear end ratio for better highway mileage?

 

[Pappibri]

Welcome and I have to find them pics you posted and check out your rig...

 

[SuperBuickGuy]

Average is about 14-15 mph. Actually recorded a max of about 19 mpg on Interstate 40 after a hunting trip...

my 5.3 is lucky to get 14, best is 15 - so swapping to a 6.0 or 6.2 may be in the cards, plus it'd be nice to have a bit of extra power

 

[Schwarttzy]

Welcome to the forums here!

 

[Encycloman]

Try my "secret recipe" for mileage! I used to run a BMW X3. No matter how I drove it, I'd end up with 21.2 mpg. Found out the factory oil was compatible with something I've used for years. Added it, did NOT change the way I drove, and the onboard computer jumped to 22.7 mpg. The secret? Standard STP Oil Treatment! About $3.00 at WalMart.

 

[Encycloman]