Here is a question I have been watching dozer since I was a kid when did the D9 go from flat tracks to high tracks and has A D10 always been a high track machine,
I'll stick my neck out and say the first hidrive was a D10 and you are correct in there was not an oval track bigger than a D9.( by Caterpillar ) I think this was about 1979/1980, give or take a decade Then some realignment of numbering took place that I have never managed to get my head around, something like the 10 became a 9 when the 11 was built which was actually a 10 but twin stack :beatsme but I will now get lampooned :tong Fire away I can take it ( ducks behind prebuilt sandbag wall )
D10 was always "high drive".I think the d9h was the last flat track model,D9 got the high drive in the middle to late 1980's.I think you can still get a d7g with the flat track.Dont hold me on the exact year.
I think the D10 prefix 84W came out in 1978 then the D9L 14Y started in 1980 through to 1986-87 then the re jig of the numbers came about as AtlasRob mentioned. The D10 became the D11N in 1987( with many changes) and the 9L became the D10N in 1987 also, with an intercooler and a longer track frame and no doubt many other smaller changes. 25c is correct that the 9H was the last of the "flat tracks" in the D9 size.
D10 76W was first. The original prototype sits on the lawn outside building KK in Peoria. It was like a couple of years later that the much better 84W series came along, not that they didn't have their fair share of troubles. 14Y D9L's started in early eighties and early production models were down more than they were up I think. Powerful cats they were, to powerful for their undercarriages.
G day surfer-joe, what did you mean about the undercarriage being under done for the power? Here in the west of oz the 9L ( certainly not the D10) would go down as one of the best machines that cat has done. However you may have a bit more experience or been around a little longer than me (no Im not calling you old!) and as the owner of a 9L Im curious to find any issues that I might have in the future. Cheers.
Oh brother, I could write a book about problems with early D9L undercarriages. I lived, breathed, and slept with a couple of dozen of the dern things for two years in three Kentucky surface coal mines. Our serial numbers started in the 90's and went up to about 130 I think. In fact, there isn't any part of a D9L that I didn't touch in those two years. Any D9L in existance today has likely been recalled and rebuilt many times from the frame down, well, from the hardnose back, or is it from the rollers up? Anyway, I am betting that all the early lightweight roller frames have been replaced or heavily modified. The hard bars have all been updated, the pivot shafts and bearings have all been upgraded, and anything left over has been replaced a dozen times. That would include the roller brackets, the stops, the recoil spring and track adjuster housings, seals and tubes, the idlers, well, everything. The original D9L parts book was about a half inch thick. The last one I saw was about three inches thick and there were two of them I believe. I was quite happy when the D10N models replaced them. Cat finally woke up and beefed everything below the seat up to where it should have been in the first place. When the bean counters controlled Cat for a few years in the late seventies and early eighties, they about ruined the company I thought. Then there was the confusion over the model numbers about the same time. Not good. In later years I had some experience with later model D9L's and even many of them were heavily modified in the U/C area. There was a constant stream of PIP's about the machines for a long time. It took considerable experience in the field before Cat conceeded that they needed to make major changes to these tractors. I think they have it down pretty good now. What you need to do "nextdoor," is get your hands on all the Cat PIP bulletins that concern your serial number machine. Your local Cat house should be able to do that for you. It can be done online too, if you sign up for Cat's SIM's program. They will probably invite you to do that, but is is a little expensive. The paper bulletins are probably a better bet for you. Good Luck.
I believe the numbers game came about when Komatsu got serious about their big dozers. The D375 was just a little bigger and a touch more powerful than the D9L. Both had about the same undercarriage but the low drive Komatsu cost almost $30,000 less. They lasted about the same amount of time to start with but after a few years Cat made mulitple changes and got theirs lasting long enough more to make it interesting again. At any rate there came a big game of changing weights, sizes and horsepower ratings per each model. Komatsu changed a bunch of models and Cat seemed to do the same to mate up better against the new competition. The same thing is going on in excavators right now. An example might be the 400 model excavators. It seemed they have all become 450 excavators. The only difference I see is that they have added extra counterweight.
As informative and understated as always, a true gentleman. :cool2 :drinkup
Gday surfer-joe, sorry Im a day or two late but Ive been a bit busy and thanks for your info. Im due to start a major job on the undercarriage shortly (have been putting it off for ages!) and I will post some pics when we do it. The machine is just used around the farm but I still want it kept good condition (despite the fact that it only does 100-200hrs a year) so I may call on you opinion when we get it stripped. The main issue is that the cannons are leaking so I want to jump onto it before the problem gets worse. Cheers.
G,day Nextdoor.....I'll come on out and give you hand...no work down here...Narambeen isn't it??
I dont want to rain on your parade Squizzy but that 1/4" drive socket set you usually have handy for the mini digger probably wont be quite man enough for that job :tong
As Joe said, the later D-9L's and those that survived enough updates, are pretty good now. I have one in the high 1400 serial # range, and it has all PIP's done. It is a very good tractor. Still some problems, but none you would not expect working anything in hard rock. I have never had much use for the D-9N. It will barely outdo a D-8 of any series but an "N". The only good thing is the bottoms lasted longer. I think it is because you can't get enough work out of one to wear out or break anything. Same with the D-8N. When they went to the D-9R and D-8R, the game was definately improved. The D-9R will nearly get as much work done as the "L", even though it is lighter and less power. It is enough faster and better balanced to nearly make up for it. The D-9R does have a tendancy to snap the EQ bar on a regular basis. I had the records when I got it used, and it had the EQ bar replaced 4 times in the first 9,000 hrs, and I have gone through 5 more in the next 10,000 hrs. Made nearly 17,000 hrs on all original components though, except U/C of course.
Its alright Rob...I got a coupla big spanners up the shed.....last gearbox I re-built was a David Brown...only 25,000 Shafthorsepower.
Make sure they are not whitworth
Now, now Rob arent they an invention from the old country!! lol.
Don't get me started..... Whitworth was the easy part...ringing Colchester to get custom made lead screw gears to screw cut Two Start, Left Hand sqare "Admiralty Pattern' thread takes the cake for British engineering.
Ye, I just assumed Squizzy would have took his tools when he left us after all you all started from here didnt you? :tong :dizzy
My family didn't have to pay the 10 quid....we got a free trip