Seems to me that weight is a problem.
Not if the aircraft in which you plan to move it in can cheerfully handle either, and is limited from carrying a third vehicle inside due to bulk and spacial limitations rather than weight.
I'd think a more real limitation would be found in Korea, where many of the bridges are Class 50s that won't take the weight of either a Crusader or an Abrams tank. But noone has suggested getting rid of all our Abrams tanks to take on North Korean tank divisions with good intentions instead, should it come to that.
We sold the South Koreans a bushel basket of our reworked M48A5s for a little over $1000 each, a real bargain, and just light enough to be workable over those bridges, [even M60A1s were over-heavy] while American M1A2 Abrams tanks did the job where they could. A similar mix of Crusaders and M109A6/A7 Paladins would seem to be the redleg equivalent.