Can anyone help ID this blade which is on Cat D6 #5R4638? I looked through the blade manuals in the ACMOC library but couldn't match any part numbers. The large left cylinder leaks and I'll need to have it rebuilt in the not too distant future.

The blade itself measures 118" wide, just shy of 10'. On the back side (facing the operator) it says "Ag Only". It looks like some of the mounting brackets were moved, so this blade may not even be intended for this machine. The only thing I know about it is that the previous owner replaced the smaller tilt cylinders about 10 years ago.

The only two parts numbers I could come up with are 1J509 and 1J51021, neither of which is "valid" on Cat's website.

Thanks in advance!

That's a shop made blade (non-Cat) with Cat tool bar mounting.
Found this on the 1J0509.....
cats.klaxon-parts.ru/caterpillar/82-54122/
 

Thanks Old Magnet! In the ACMOC library, there's a parts catalog for the No 6 Toolbar, 76C1-up. The diagram on page 8 is very similar to the one you linked, and includes 1J509.

I am new to heavy equipment. What does the "ag only" on the blade mean?

Your blade looks like it was built for pushing silage. It would not stand up to the abuse of cutting dirt or pushing out stumps. You could probably get away with some lite grading on loose dirt or gravel. The blade might be able to be reinforced for dozer work but as is I'd be careful.  Might work fine for snow removal 

Thank you d2gary, I think you are on to something. From what I understand, the machine was used for road maintenance and snow removal the last 10-15 years.

This morning, we walked around the property where the machine currently is, and found a second blade. Can anyone id this blade? It's 95" wide, and ~81" from the top of the blade to the end of the mounting arm. There's a little yellow paint on it still but not much.

 

 

 

 

 

That looks very much like a Dakota blade. A after market brand from 60's to 80's. Just guessing, this second blade is the width for a wide gauge rather than your narrow D6.
Looking at the turions on your tractor it looks like the second blade arms would fit if the current arrangement was cut off of them.

My first thought was your blade had been extended higher to push loose brush like orchard pruning's. But if improving a blade for that teeth on the bottom like in d2gary's avatar picture would be more important in my limited experience pushing pruning's But once pointed out the piling of silage make perfect sense for your blade. I would not want to guess just how tuff your current blade is. But have seen some ruff and tumble operators beat on a Dakota blade and not break it. But it was weeks of work not years..

Thank you Ray54. I'll try to get some more measurements when I go up there tomorrow.

I was hoping to use this machine to reopen some roads on a property that was abandoned the last 30 years. I also need it to drag a poison oak-infested D2 to a better location. We'll see...