<span style="font-family:Arial">Some may recall my posts last May when my lovely wife of 32 years “allowed” me to get a D4-6U (44” Narrow Gauge) Cat for Father’s Day (Dad had a 1950 6U when he farmed, but traded it in for a John Deere Model R before I was born)! Well, it’s been quite a summer doing un-related home improvement projects and also constructing a building to house the D4 and my new equipment trailer. (I just can’t stand to see equipment sit out and deteriorate!) Anyway, so yesterday I finally got the D4 inside, with the trailer, one day before the rains began for the winter! I hope the old girl likes her new home! Plus, I’ve now got a place to do maintenance and restoration!</span>

<span style="font-family:Arial">I also have to say that our newest “family member” really earned her keep already! Besides pouring a concrete slab for the new equipment building, we added to our existing concrete driveway. When I had to dig down about 8 inches below grade for the gravel base and the new slab, the soil was so hard and compacted that had it not been for the rippers on the D4, it would have been a real struggle to remove the approx. 20 yards of material! As was said on this site by someone back in May when I went to see this D4 for sale, a D4 with rippers (and a blade) is a very functional combination! Boy, were they spot on!</span>

<span style="font-family:Arial">Enjoy the photos! Yes, that’s my daughter Renee; right after her first time “behind the wheel” just before I put the D4 in the shop. She drove all of 20 feet in 1st gear, then back in reverse! What fun – her Grandfather would be so proud!</span>

<span style="font-family:Arial">Lastly, I still don’t know the make of the Rear Rippers. I only know three things about them. 1. They work great! 2. They are NOT homemade as the heavy (1/2” to 1”) plate is professionally formed and they have two heavy support bars that extend from either side of the rear mounting plate forward to the drawbar attach point. 3. While I haven’t seen any I.D. plate yet, the hydraulic cylinder housings appear to be a Cat part number – “1K5830”. So guys, who designed/made these rippers???</span>

Can't identify the manufacturer for sure but appears to be a heavy duty knock off of the scarifier attachment that was available for the HT4 Shovel (would fit all D4's)
Nice piece.....lucky to find one.
Main difference is that you could still mount a PTO on the Cat version.
Very nice out buildings.

That unitis called the 1K94 Hydrulic Scarifier, first came out in 1950 as the Trackson and went with the Trackson HT4 Traxcavator Shovel that were attachments to the D4. In 1951 Cat bought out Trackson and made the intergated Caterpillar HT4 Shovel that was a basic 7UD4 but looked totally diff from and in 1956 they came out with the No 4 ripper and changed the design of the ripper to 1 cyd paralellogram type so if its 50-51 Tracson, Late 51-55 its Cat The 1K???? numbers were used on both Cat and Trackson Loaders
Very nice looking and usefull machine you need to find a front gaurd for it and would look even nicerand protect the Rad. and hyd unit too

Doesn't quite match the 1K94 either....

Be cause you are looking in the Brown Cat Parts book you need to look in the pre Cat YellowTrackson Co. parts book

OK, thanks
Can you post the parts breakdown picture for Trackson.

I cant find it I only find the T4a nd IT4, HT4 is missing and the 1K?? is only Parts no.s and parts groups the ser no. are HT101-HT2800 and 35C1 up but when Cat took over and reprinted their own books they only have the Cat upgraded parts

Also if you look close his is 60in model with only 5 shanks for the 6U and the 80in has 7 shanks for the 7U

Yes, I got the narrow vs wide option but it's the mounting frame and the lower draw bar bracket attachment (under the tractor) that I was interested in.

Wow, you guys are a fountain of information!

I am guessing the Rippers were added later in its life, as it has a homemade selector valve set up. Additionally, as the photos show, the rear vertical flange on both Fenders was torched out so the tops of the cylinders had room to fit! Do either of you have parts diagrams looking from the side of the 1K94? It looks so much like mine except for the difference in the mounting plate! If you guys could nail down the maker, perhaps I could get lucky and get manuals for the Rippers! Are there any images of the 1K94 unit for a 6U? Like Mike Mc, I’m always open to your suggestions and knowledge!

Willie, I have the Front Guard (and the engine side guards) I took them off for the pressure washing she got right after I got it home in May. My radiator grille is off too as I need a new one since a previous owner cut off the vertical center bars!

Overall, this Cat needs a lot of TLC to fix stuff that others messed-up over the last 55 years such as; a broken off bolt in the Nose Guard attachment. Fix the cutting torch cut-outs on the engine side panels where the belly pan attaches in the front. Replace the hacked up Radiator Grille, Re-do the homemade plumbing & selector valve to switch between the front blade and the rear rippers. Replace the non-Cat Hood (however the galvanized sheetmetal reproduction is not too bad.) Replace the Pony Motor exhaust pipe as it was cut and re-welded at 90 degrees so its all under the hood with a door hinge flapper for a cover!?! A messed up Battery Box with no Lid. Perhaps change back to original, the conversion to a dry air filters (primary and secondary). This may have really been beneficial for the engine as non-maintained oil bath filtration isn’t good!

My 5 (to 10) year goal is to restore this D4 and correct all the stupid things and bring her back to all original Cat parts and configurations to include new paint and decals! The big plusses are that the undercarriage is at 40% wear (except it could use new grousers) and that she runs and steers great! I’ve already bought several hundred $$ of parts, filters, and new lubricants from my local Cat dealer – Holt of CA. I also bought complete manuals from Cat reproductions for all but the Ripper. I have yet to take off the “curled” inner Track Roller Guards, so I can take off the Belly Pan to change all of the fluids. I’m at the beginning of a long journey, but I can visualize the results already! So much to do ………… and so little time!