Subframe installation question

JayW

New member

Equipment
B2400HD & 4672 backhoe
Jun 29, 2021
5
1
3
Salt Lake City, Utah
I haven't been able to find a subframe kit for my Kubota B2400HSD that I bought used (with a 4672 3 point hitch backhoe).
As many others have found, the tractor frame is not up to the stress the backhoe applies, and I've just had the frame fixed. To prevent it happening again, I would like to install a subframe similar to what is on the more recent models, but I can't find a kit for this older model.
It looks like it would be fairly simple to fabricate from some plate steel that would go from the rear axle to the loader mount.

One issue is the 4 holes on the outside of the axle casing are not threaded. They are about 1 1/4 inch deep.
Can I safely tap those to mount the subframe? If so is there a recommended size bolt I should use?