Mounted rippers were not uncommon on 'U' series tractors, they were generally mounted differently to later tractors, they had a plate or long bolts that were attached forward to where the Drawbar pulled from, that way not all the load was on the studs in the housing at the back. In Oz many D4 7U tractors were fitted with rippers for soil con work.
D4D D5 D6C tractors to my knowledge all relied on the studs at the back like later tractors, in Oz it was common for those models to be fitted with rippers, there are very good aftermarket rippers out here that I believe are superior to Caterpillar rippers, even D6H and later tractors are generally fitted with variable pitch rippers.

Wombat

Hi All,
Wombat is correct as I have a D4 7U that has rippers on the back of it. It has connection bolted on the bottom of the mounting frame that goes back to where the original drawbar connects (the original drawbar is replaced) you can see it in the attached photo.

 

Regards

thanks for the replies guys...

-my neighbour has a D7e with a ripper, nice unit, uses it in a gravel pit along the river..
-but i haven't noticed a ripper on a 6? i think it is rather rare in North America as others have said..
-and i believe the shock loads on the back end can be crazy, ripper or winch
-it even surprises me how tough tree stumps can be to bust out...good thing Cats are built sturdy

Hi All,
A photo of the rippers on my D4 7U (forgot to post earlier)

 

Regards

Hi, PhilC.
Yes, there was/is another reason why few people fitted rippers to the older small crawlers quite aside from the fact that their back ends were not built for it - they didn't have the weight and horsepower to do any serious ripping. Yes, they could soften up most SOILS to make for easier working but they were almost as much use as a breast pocket inna G-string when it came to serious rock.

Just my 0.02.

Hi Daryl,
that looks like a Standen style ripper that we used to fit to machines sized from D4 to D7 at W Adams. back in the 1960's when I was an Apprentice in the New Equipment Bay-- Mr. Standen used to often appear when a new model machine or one they did not have rear mount stud drawings for and make a template to suit for the back plate.
Soon enough a nice new ripper would appear usually in Red Oxide paint. All part of the Australian built theme of the day as Cat Of Australia were producing D4 and D6 TTT's amongst other items of plant and attachments, including undercarriage items for same.
Cheers,
Eddie B.

yes darryl that is how i would mount em if i made a set for our machine. many farmers have snapped tractors in half mounting front blades etc simply becuase they dindt pick up mountings all the way along and particularly at the diff. here's something to if you want to make a machine to pull at its maximum run your chains to the front you get more traction as it is pulling the machine into the ground its also safer much less likely to flip the machine. and any machine will break if you abuse it.

Hi Team,
further to the Standen or any ripper for that matter, the lower edge of the ripper mounting plate is that it hangs down below the bottom edge of the rear case face and there is a ripper specific drawbar tongue that is to connect to the drawbar mount under the transmission case--there is a specified shim adjusted preload applied to the draw bar tongue to the ripper mounting plate/frame to ensure that the pulling power is taken via the drawbar mount and not by the studs on the rear case.
Will see if I have these specs from a Cat ripper somewhere here.
It is not all brute force and ignorance with these ripper mounts as you will now appreciate there is some science to it for a successful ripper out come and so not RIP the ripper off or the rear face off the rear of your machine.
Cheers,
Eddie B.

Hi, edb.
I never saw the ripper mounting brace that you have described onna small dozer but I saw a good few of them on Cat 941 track loaders, seemed to work well too.

Just my 0.02.

This came with the tool bar set up on my 7U D4. Almost all the force is on the trunion balls on the side frames.

Caterpillar called it a "subsoiler", not a "ripper". It also has a mole attachment for drainage work