On Apr 23, 10:54*pm, "rb" wrote:
I'm considering using a 4"x4" for a crosspiece to put a chainfall on and
pickup the front end of tractors.

What I'd do is use scaffolding sections to get the height I need, use the
4"x4" for crosspiece, and honk up the front ends for blade changes.

About max weight would be 1000lbs of tractor. Front end would probably be
around maybe 600lb.

Will the 4"x4" hold these loads?

Risky. Use a pair of 2 x 6's nailed together and standing on edge
(vertically). If you're using standard 5' x 7' scaffold sections, an
8' long 4 x 4 could easily be overmatched. Doubled 2 x 6's close to
the scaffold verticals will give you the support and safety needed,
just as on a construction site. HTH

Joe