99 yukon 5.7L with no cats
I towed my cousins car on my trailer had lots of power considering how much weight. My Yukon is lifted 6 inches with 35 inch tires, not geared just exhaust and chip. Helped out a lot! Only issue was fuel consumption on extreme performance mode, but would be fun off roading
I bought this for my 02 yukon expecting better mpg and hp. I have noted a 4-5 mpg improvement for highway driving, but no improvement for stop and go/city driving. As for hp I have yet to notice a difference. I have aftermarket intake and exhaust upgrades on my truck and expected this device to make a noticeable improvement but it's just so so. I may connect a back up camera to it in order to get my money's worth out of it. The shipment of this product was also extremely delayed by the manufacturer and Auto Anything only notified me after taking my money. Bottom line decent product but high priced, crappy customer service.