| Do a search on mouthpiece, that will help, I was getting 18 reliably before the mod, have not had it on long enough to see how much better it is but as you will see, it helps. The size of the tires will make a difference too. Is the truck stock or has there been modifications done to it? Like bigdaady said, there are alot of variables.
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'05 GMC 2500HD, CCSB, LBZ mouthpiece, A.R.E. cap, N-FAB nerf bars.
Winter truck- '98 GMC K1500 ECSB Z71, 125,000 one owner miles, custom buckshot dents in driver's side cab extension and front of box compliments of 2am drive by. www.performancetruckproducts.com |