Unfortunately swapping in another non oem trans would be cost preventative as opposed to having yours rebuilt. Should it have held up longer, sure , but I dont think you'll find to many people praising Chrysler built automatic. Doing a manual swap is probably more reasonable but still the AX5 is not considered a HD trans. My 91 runs 31's has a 4 and AX5 and it has 150K on it now and works just fine for trails and highways at 70. I will admit I rarely use 5th gear though.