Thanks Grant. So I am hoping to transfer the track frames to a 7u d4. I do have the oil pan from traxcavator. So possibly swap also if needed. I have a picture of D4 7u I'm going to purchase when things dry up in spring. I can't load picture, i can't get any blue line to happen. It has ok undercarriage, I think bottom rollers a done. Needs shoes too. I have the track frames and chains from traxcavator, so I figured I may try this. Traxcavator chains need shoes also, I would consider shoes from a 955 if I could find some. Also I would try for manual angle and hydraulic tilt on this machine. I want it for grading my roads. This d4 I plan to buy also has a carco model A winch on it, which is a bonus also, my property is forested so I chop quite a bit of firewood.

I have read the instructions for adding pictures, seems so simple, then I realize, so am I.

I would advise against putting the 5 roller frames from the loader onto the D4, it can work, but you will end up with a ridged (non oscillating) frame dozer with extra long track assemblies. The loader frames are longer than the standard 5 roller frames for the D4, so not only will the tractor be longer and rigid, and thus harder turning, the standard dozer C frames will not fit, and you will need to swap the oil pan and other parts.
Best to keep the D4 standard and learn how to use it.

Hi All,
Yes the oil pan is different on a solid bar to a equalizer spring type D4 tractor.

Regards

Good info for me because I have a 7u traxcavator and a 5 roller 7u dozer. I considered this conversion until I started looking at everything that had to be swapped and modified. I wasn't aware of the track frame length difference but I did measure the 2 sets of frames and the traxcavator is quite a bit longer.
I will be using the tracks and will salvage as many of the bottom rollers that are useable. The sprockets have been rerimmed so those will go on my dozer.
Looks like I will have to shorten the chains a couple of links. I havent counted the links yet but I thought I was cutting a fat hog because the traxcavator tracks have alligator master links.

Hi d2gary,
On the Traxcavator it will have larger front idles you may want to put them on the 7U too if yours don't have them and then put the chains on, as you may only have to remove one or two links.

Regards

Even trying to use the large idlers from a loader on the standard 7U may be difficult, several different idler assemblies used on the loaders and all different from what used on the standard tractor, not saying it’s impossible, but best to do the research on what idler assemblies you have on the loader/donor and what parts and modifications it will take to work.

What are potential issues with loader idler. Would the mounting setup be different, or is larger diameter problematic, or both?

I am in the process of scanning the 955, 12A 01-up & 955, 42D 01-up parts book Master Copy for the library. Then I plan to scan the 955 12A 01- up, Service Manual. Somewhere in the information it is described why the Traxcavator D4, 955C needed the extra rigidity because the extra load on the front and extra lifting capabilities.
An interesting thought is the 955A Bulldozer 42D a Traxcavator with a dozer blade.
2K4725 Bulldozer Arrangement, 9F2348 blade group... 42D 01 - 42D 0311
2J7145 Bulldozer Arrangement, 2J1136 blade group... 42D 0312 - 42D 0328
3J0854 Bulldozer Arrangement, 2J1136 blade group... 42D 0329 - up

The major issue with using large idlers from a loader, (depending which loader idler group you have) is the idler bearing group is different and mounted to the track frame in a different way than the standard idler. It's likely that you may have to modify the track frames by adding a strip assembly, 7B5955 or other strip assembly to the inside of the track frames to be able to use the big idlers, you should be able to see these parts in the parts book.