Czar

I know the J&M cart is very well balanced with not excessive tongue weight (unlike the Brent or Kinze) of 4,200 lbs loaded

Are you saying it's bad to shift more weight from a 70,000#+ load (includes e.w.) off of 1 axle (I assume 1 axle cart) to the rear of a tractor, that would probably have duals on it anyway (here!)? Personally I don't consider the wt xfer a bad thing. When we had the MX240 on a cart, we added the CNH drawbar support kit. I think it was good for 12,000# or something. I'm sure that much weight did NOT go on the tractor though.