To answer your question 8c 361, the D8 was used very successfully in the all the hills of northern San Luis Obispo and southern Montery counties. It included all models from the old slide bar up through the 36As. I don't know of any D8K's that were used but I'm sure that had more to do with the economics of the grain industry at the time they were offered for sale. There was even a hi-track D8 used in Shandon for a while. Another ran a late model IH TD25 which was a bit more animal than the 36A. The later equipment pulled 42 ft offset discs while the 2U and 13A & 14A D8s pulled 30 to 36 foot discs.
There was a large number of D7's also. The 3T was very popular and in good numbers the 17A was also popular but the numbers were low. There again, I believe it was due to the economics of the times. When things got better, quite a few D7E's and several D7G's were sold. I don't remember any direct drive D7F's.
My grandfather used to disc the coastal almond orchards in the 30's and into the 40's. he had two Cat 35 diesel. When the D2 and D4 came out the grower bought a fleet of these smaller lighter tractors.
Grandpa said that they used to roll one or two of them over every year from making turns at the bottom of the hill at full speed. When they replaced them with the 4R and 9U D6's the overturned tractor became a thing of the past.

Casey Root

It would be true that a 9U with a dozer would be way too clumsy on a hillside doing farm work.

However, the 4R and 9U and I would guess the follow on D6B and D5 were the best tractors up to their time for both power and stability on hillsides. ( I was gone by the time the D6B hit the hills so my knowledge thins out there)

I have considerable experience with the 9U and I can tell you it was an extremely stable tractor on the hillside due to it's balance. It did not yaw or dig a hole. If you set it and essentially left it alone it would migrate across steep slopes and not leave a mark.

With combines it would slide a little but always in a controlled way, that is it would not nose up as some tractors tended to do. I've pulled a 36B along steep slick hillsides with the 9U where the uphill track is ticking the mark and the header is barely taking 4ft.

I loved the 9U and would defend it without hesitation.

These days in this area things have changed considerably, minimal tillage has changed the terrain and the size of tillage machines has grown in response. In this area anyway, steel tracks have given way to rubber and Quad Trac.

Where we used to load cats and machinery to move they just take off down the hiway now.

In the 70' and early 80's we ran both a D6C 74A and an AC HD11 AG. We had them setup to where the power was identical. The HD11 was a far better balanced tractor and negotiated the steep hills with ease. On a steep side-hill with a reasonable load the "C" would nose up hill, climb on the sprockets and bounce along. A most uncomfortable ride and a berm of dirt below the track that would often plug the implement being pulled. Especially a disc. We found a great deal of relief to this situation by lowering the draw-bar 3 inches. Doing so put the point of pull farther forward and created a much better balance. Cat also recognized this problem and remedied it in the D6C SA 17R. They put the draw-bar lower, farther forward and a weight block under the radiator. It is my understanding that the SA models, in the D4, D5, D6 and D7G were all a well balanced unit. I would like to have owned one, especially the D7. HP is fun!

Casey

Pic of 180 hp D7E with 15 bottom plow.

I have farmed a lot of ground with a 9u D6 and a hydraulic pump and hardnose with rams on the front in some places would be better without,but some times it helps.I cultivated a very steep walnut orchard for a neighbor and he wanted me going up and down so I used a smaller disc and was still spinning and just making it up the hill and I had done the same ground 10 years before and didn't remember that much spinning.Then I remembered I used the D6 with the hardnose on it more weight on the front keeping it from having to spin down until the full track is making contact with the ground ever time I crossed a disc berm.But going across the hill it would make the front fall so you do more steering to stay up the hill.

"ROME/KG" wrote:

Pic of 180 hp D7E with 15 bottom plow.

Interesting transmission setup but no D7. Looks like something I would do.

Hi, O-I-H.
LOOKATTITT! If'n yer look VERY carefully in between the two transmission diagrams, yer may just catch a glimpse of a horizontally oriented long, narrer-gutted foter of a D7E pulling TWO plows in tandem. Er at least that's what my pore, tired, ol' eyes are telling me is there.

Just my 0.02.

Goog on ya Deas I didnt see the picture until you wised me up to whats going on thanks mate

Paul