Took it on a 5hr trip last weekend. Keep in mind i have NO O2 sensors hooked up and the MAF disconnected so its running on the revert MAP tune only (less than ideal for mpg’s), no overdrive , running stock 4.56 gears. It got 17.4 MPG. I was actually impressed with that considering all the above. Just with the OD trans it will be in the 20 range and when i do hook up the maf and o2’s and do a little laptop tuning magic it should have no problem getting into the mid 20’s range. Im assuming it will get about what a new gm gets. Probably around 27mph highway. Cant beat that while cruising in style!
