The early U series still had the thinner plate fenders with the formed outer edges.

Hi, cr.
Just out of curiosity, do you have the serial # for the changeover?

Just my 0.02.

That tractor has some stories behind it, the draw bar shows a lot of wear. Looking like what ever put that wear there had a good amount of tongue weight. I am not an expert on dozer blades, but this one looks more like after WW2 to me. Or at least this was much less cumbersome than other early hydraulic dozers. Not that latter builders did not find they could leave a bit of iron in the shop that they put on this one.

So, what kind of work did the tractor do before this blade was added. As for the brush canopy, it looks as if it could of been built a bit stronger. But anything helps if you have ever been slapped by a tree branch. Why I built brush canopy on all my D6's used in orchard cultivating.


Have never got into D4's so not up on the serial number changes. But the D6's went to the heavy fenders in the mid 50's. Probably at the 9u 13263 when most of the other changes were made to the U series D6. Would guess the D4 would of been real close in this change.

I didn't notice the draw bar wear you reference. What do you look for? I did notice in pictures where the draw bar became thin from sliding on other machines, but the draw bar on mine is locked, with 2 additional bars added for pulling strength. I didn't notice it getting thin.

I think without a doubt this D-4 was used in logging. I got it in prime Oregon logging country. It may have belonged to a logging company at one point, but spent it's last years in private hands logging a 20+ acre homestead. Probably the last 25 to 30 years in the shed I pulled it from. The 35 year old quart of oil under the seat hints it could have been at least that many years. This picture I'll include here  is right outside the building it was stored in. It gives an idea of the country side. This is logging country, about 6 miles from the closest sawmill.

I certainly hope this dozer will run again. It's on 80+ acres of forest land right now. The land already has been logged for the most part, but if the dozer has some life left there is plenty of work for it. Any D-4 can be brought back to life, as I have witnessed on YouTube, but if it requires too much to get running again, it probably won't be me.

  Drawbar wear

Thanks for pointing that out, but does that spell work for you at that angle of wear down low, or just a clevis, or the like dangling, rubbing with every tractor movement?

My D4 6U serial #6070 has the heavier fenders. The Hyster that came off of my fathers RD4 originally came off of a T. The early Hyster mounts for RD4s/D4s came with long reinforcing plates that you removed the fenders and put the plates under the fenders. I measured, and my 6U fenders are thicker than the Hyster reinforcing plates. The photos of yours make it appear that the upper mounts are bolted to the underside of the seat. Is that what I am seeing? I will take a look at my winch tomorrow and see if it makes sense to me. I will try to remember to measure and see if the winch is too wide for a narrow gauge D4. The D4N winch may be wider than the straight D4 winch. The fenders on yours look to be torch cut, so probably shop made since the originals were so weak. We are always learning. Grant.

Grant, The right side is torch cut for the brake. I didn't look too much at the left side. Light weight fenders wouldn't make any sense in a logging environment, and I think that's where this dozer spent most if not all of it's time. I wonder if Cat would have sold fender upgrade kits after the heavier fenders came out.

6U 5843
7U 11952

Here is the link to the Hyster, now Allied Systems manual archives, you can see the books for the Winches, which will also show how the fenders are to be cut along with the other items for mounting the winch.

www.alliedsystems.com/pubs/pubs.php#

The Hyster D4, D4N and D4D could be used on the D4 tractors from the beginning up through the U series, and wide or narrow made no difference.

The canopy on that tractor looks like a Fleco, fairly common on logging tractors back then.