I know what you mean about real life height. I actually had purchased a 2006 Dodge Ram 2500 Laramie last year. It was located about 3 hours away and was ready to go pick it up. My last second thought was would it fit in my garage since my current truck was a dodge ram 1500 and was VERY TIGHT in height clearance. Turns out that the 2500 was around 5-6 inches higher, I ended up canceling the deal because of this issue. I will not park a $50,000 vehicle outside!

As for the Tahoe, I seem to remember my garage being around 78-79 inches and no problems at all with clearance.

 

I haven't measured my garage door. But my 07 LTZ (4x4) fits in the garage just fine. It is a little close but not a problem.

I also have 24's with 33" inches of wheel+tire overall, which makes it sit an extra 1.5 inches higher than stock.

My tahoe is actually taller than my co-worker's 03 1500HD 31" tire combo.

 

Just checked my stock 4X4 w/ factory 20s and it measured 76" (6' 4")at luggage rack over rear tires. That was the highest point I could find.

I also had to worry because my driveway is on an incline and the floor is level of course. As I back in, the rear is really ramped up compared to normal ride height.

 

Thanks again guys... no it is just a matter of time until I have one. Thanks again.