Depends on the axle. They can be anything from a 2.41 to a 3.73. They can take a fair amount of abuse with normal weight wheels and tires. Those 22's probably weigh 35-40 lbs each. For reference, my 16's weigh about 20 lbs each at most. You are talking about another 40 lbs of rotational mass you need to accelerate. Think of the axle like a fish scale. on one end you are holding it up, on the other end you have a fish. The fish is inertia keeping you from accelerating. You holding it up is engine torque. The drivetrain is in the middle. If you put too much weight on it, the spring in the scale will go beyond it's ability to spring back into shape and will break. The same goes for your axle, driveshaft, transmission, etc. It's a tug of war. Eventually, given enough force on either end without the other side giving in enough, the rope breaks. I have no experience with wheels that big on a G body because to me they do not make sound engineering sense (and I am going to college for Mechanical Engineering rt now...). It may well take it if you don't drive like I do. Then again, it may not. Remember that a heavier object resists movement more than a lighter one. So, it is easier to spin a lighter wheel than a heavy one. This is why many of the actual performance oriented import people run 15 in wheels that weigh around 9-11lbs each, like the Konig Helium or Volk TE-37 on their Civics and Sentras. They also run very light flywheels for the same reason. A Honda B16A (1.6 liter DOHC VTEC 4) with a 9 lb aluminum flywheel will rev VERY quickly, almost like a bike engine as compared to a stocker which has a iron flywheel that probably weighs 20-25lbs. Heavy rotating parts take a lot more power to accelerate vs light ones. Rotational weight reduction therefore is the best kind of weight reduction since it helps acceleration far more than static weight like hoods or doors. Also, with your 29.5 in tall combo, you are close to what a Jeep Rubicon has in stock tire height, which is 31 in tall, IIRC. The Jeep has stronger axles though, with a Dana 44 front, and a beefy rear. You have a GM 7.5.