Hi everyone. Im considering buying a D7F dozer to do some work around the farm and would like to know what im getting into before going any further with it. I have read some information on them and got conflicting opinions as to the reliability of these machines. I don't have a lot of information on this machine as of yet but I do know it has the 6 cylinder engine and is a 1977. It has a semi u blade and 3 shank ripper. The under carriage im told is about 60% and total hours are unknown. It was bought at an auction 3 years ago and the owner has since passed away so his daughter is selling it now. She said he used it for about a week to clean up an old yard site and that was all. What sort of things should I be looking for on this series of machine and are there any real problem areas that I should watch for? My plan is to clear some brush and burry rock piles with it as well as cut down some high ridges and push the dirt into the low spots beside them. Will I be able to dig down decent for burying rock piles or will I be having to make a long trench to get a big enough hole? I will be going to look at it on the weekend and hopefully be able to run it and get some pictures and more information. Thanks.
D7F made in 1977?? I think this may be a typo. By 1977 Cat was well into making D7G's. Could be a real late F made in 77 I guess. I ran a 72 or 74 D7F and they are good machines. Pics are always nice. Good luck with it. Lowbed Driver
yep the D7G came out in 74. The early Fs were a problem but the last of them were ok; all depends on what serial number.
Hey mate if that dozer has been sitting that long b careful this could turn into a can of worms if it were me if I could afford it afford it I would try n find a G ur getting away from pilot motors ( cantankerous pigs at the best of times ) and get in to a 3306. The G is more common easier to get parts and info 4.better injection and stuff. That's my 2 cense worth any way.
I have a serial number!!!! 94n5775. I talked to the daughter again and she gave me her neighbours number who knows a little about the machine. He said as far as the year he thinks its more like an early 70s machine and from what he remembers it should have the newer smaller transmission, it does have the 3306 engine and injectors and turbo were supposed to have been changed just be for it was sold at the auction. He figures there might be a leaking or cracked valve body for the ripper control or bad cylinders because the ripper creeps down and has to be chained up. Other than that he didn't know to much more other than it was working good when the former owner was using it. I guess now if someone could tell if that machine does have the good transmission from the serial number and actual year of the machine then I could get a better idea of what to offer for it. Thanks.
Cat updated the transmission at serial # 94N 5192 and above so looks like you are good to go. If I remember correctly the early D7F had the transmission from the D7E and the F had more horsepower and that transmission was the weak link , so to speak, in the drive train. I have heard (but do not quote me) that the early D7F's with the weak transmissions are still a good machine for the hobby equipment owner or someone who is going to be easy on the machine. I think the problems would arise from heavy dozing, pushing a scraper, pulling a scraper etc. Contractors were starting to shy away from the F model so Cat updated the transmission. Cheers Lowbed Driver
Oh yeah ...I forgot...post some pictures for us to see..... grin...cheers again L.D.
s/n 94N5775 is a 1973 machine.
yep 94N5775 has both 3306; earlier was D333C; and the later smaller transmission; problem with the earlier D7E trans was it went from 1200rpm with the D339 to 2000rpm with the D333C and it didn't like it should be a reasonable tractor. Check the magnetic screen and filter, and id also drop the final drive oils to check for sadness. If alls good buy her
Ran a 1973 94N for many years pulling scraper and clearing brush, it was a great machine. Over the course of 15 years or so replaced one transmission and 3 or final drives. I always found the final drives to be the weak point on all the low drive dozers.
I put several thousand hours on a D7F and found it to be one of the most reliably tractors we have ever owned and we have owned over 100 or so!! I would'nt hesitate one bit buying one that was in good shape to do land clearing on the farm. The 3306 cat engines were used in many application and are as bullet proof as any engine ever built. they are also very reliable and low maintenance. You will burn 5-6 gallons of fuel per hour if your working it steady. BTW I have never herd of a D7F with a pony motor for a starting system. They came from the factory with a 24 volt direct electric starting system. On another note the later model D7E's with a D333 turbocharge engine was rated at 180 horsepower the same as the D7F's with a D333 or a 3306 engine at the same R.P.M, and everyone will agree the later D7E's were wonderful tough machines with no weak links!! Yet the early D7F's that weighed nearly the same and had the same engine with the same horsepower and same transmission yet the every one claims the early D7F's had a very weak transmission and stay away from them!! Go figure! The fact is they started using the newer designed smaller lighter cheaper to build D6C transmissions in the D7F's. Frankly I don't see how it had anything to do with higher failure rates of the time tested D7E transmission, we've own and operated them both!! Yet my guess is there will be those who come and say -"No no those trannys were weak such and such told me so!!! Chum..
your all up the creek chum. ALL D7E had the 4 cylinder D339 that did 1200rpm at full load. That transmission was quite happy at that rpm. early D7F came out with the 6 cylinder D333C at 180hp at 2000rpm. The F used the same D7E transmission BUT with different transfer gears to slow it down. Trouble was the big heavier planetarys didn't like the higher rpm and they failed. Also the D333C was a lot lighter than the D339 which led to everyone complaining about Fs being lighter in the nose. Cat changed the trans to the lighter D6C style trans; but with more plates and stronger transfer gears at 94N5660. the D333C changed into the 3306, with its own 3N engine serial number and was fitted at 94N5192. a lot of people think the change occurred together but it didn't. But as chum rightly does say all later ones after that are good tractors the problems were fixed; but the reputation stuck so cat introduced the D7g in 74
Lots of good info and advice guys, thanks. Still haven't had a chance to go run the machine yet being minus 35 and wind pushing the temp down to minus 50ish I don't think the old girl would like the idea of trying to run and neither do I lol. I had a chat with a fellow who ran an early 7f and he said it was a great machine. Then they traded to a newer one with the 3306 and he said it dang near put them out of business with tranny issues so when cat put the smaller tranny in the last 7fs they traded to one of those and have been running it ever since and very little problems. He did mention that there was an issue with the transmission heating up if you worked up and down a steep slope for a long time but it was fine running on a side hill. Any thoughts on that? What about oil types, what does cat run for tranny and hyd oil in those machines? Thanks.
oil is a to4 spec 30 grade. hyd are 10w grade engine oil. D7F and Gs can get into trouble on slopes, if the oil level is low, especially climbing the trans can suck air; and there will be no go, no steering and not a lot of whoa either :eek more so on G, F is mechanical only brakes:. Cat recommend a 5 gallon overfill of the transmission when doing hillside work
Never been around or operated a Cat D7F... My uncle has. He started on the early 7E's then was impressed buy the "high horse" D7E that came in around 1970. His only complaint about the D7F that he ran was it did not have the snap & crack power of the older High Horse D7E . I'm guessing he would have been running an early model D7F. Then the 7G came along and he loved that model.
Hi TD25C any thoughts on how your uncles D7s compared to your HD16B; nosey people us crawler guys :drinkup
That's funny you ask that D6 Merv. My uncle had only ran Cat dozers his whole life working in the union. He calls me one morning and wants some clearing done. We dropped off the 16B and He climbed up on it and the first thing he said was..... " it's a little bigger than a Cat D7" . He ran it the 16 on the job while I ran the excavator. My uncle really enjoyed the tractor. Later he ended up finding a nice high horse Cat 7E that he still uses today. I'm still running the 16 .
I still have a pretty good 16B and no low track D7 of that era can compete with it, and I have had 3T, 17A E, F, and G's!! By the way D6 Merv, the 7F & G had way better balance than the than the old 7E's. The early E's were flat out nose heavy with there hyd pump in the front, always stuck!! and the later ones were still bad enough on soft ground or trying to back up hill. The 7 F was way a better overall balanced machine. Chum..
That's cool Chum Duffy , another 16B owner operator . Uncle & I were guessing the 16B was about a ton heavier than a Cat D7F or G . Is that pretty close ?
TD25, Yeah I think closer to two tons difference the 16B weights over the 7F or G!! And even though the book says not. The 16B has way more wallop than the cats, and I like the cats but it is what it is, that ole' 16B is a heck of a tractor!!! Chum..
Ran a 16B for a while for a friend of mine when his operartor went mia. Was a nice dozzer to run consider the age. Pretty quick. Was a litlte more thirsty then my 7E though. after a 13 hour day on it there wasn't much fuel left in the tank. Was push loading buggies so not solid steady work but it was working pretty good when it was pushing. It's to bad parts are getting harder to find for em. Ryan
I really like the 16B machine . Just wish I could get parts easy but that wont happen . However with technology moving forward & being what it is there are places that can tool up & make a part like a gear & such . Its expensive but an option . I will probably look for a mid 1980's Cat D7G in the future to replace the 16B . Although they don't come cheap either . From what I see on machinery trader asking price is around 50 to 80 thousand . That's allot of cash for an older machine .
Hey Merv, how many times have you yourself had a D7 F/G lose transmission prime on a steep slope then have any trouble controlling it with the either brake??? Chum
Yes they do loose prime chum, all cats will loose prime climbing hills if the oil level is low and the pump sucks air, then they go full speed astern ! D7F and D6C the brakes are mechanical only and will still stop you. D7G and D6D you will have to stand on the brakes a lot harder to stop you as they are hydraulically assited. And have had know this to happen on a D8H as well because it had a suction leak. I knew of one guy who was killed on a D7G because of this. Also Cat don't make that specific statement concerning D7Gs without reason. obviously they are well aware of it. Also disagree on D7Fs being better balanced that D7Es. Both ones I drove were bush rigged for logging. And the F would not climb as well, but yes probably backed up abit better. Also the E pulled big logs easier. A lot of people plated the blade on Fs to make them more front heavy. A bare back D7E yes would be nose heavy. esp with the early nose mounted hydraulics, have only ever seen one of them. a lot depends on how tractors are set up. My 6 with rippers outbacks its sister with a winch. weights are similar but rippers extend more to the rear.
With all due respect Merv the question was; How many times have you yourself had a D7 F/G lose transmission prime on a steep slope then have any trouble controlling it with the either brake??? Chum ..
Never have experienced the loss in prime on a slope with the 16 . My uncle talked about the same condition as Chum Duffy & D6 Merv describe with a Cat D7 on an uphill grade . He said most of the time you could let it roll back down on it's own and it would regain prime . Once in awhile if it would not roll on it's own they would use another piece of equipment to pull it back down off the slope . I don't have much experience on a D7 so this thread is interesting .
let me see chum you are the same f wit who just stated D7E and F have the same engine and trans. Obviously you never poked your head under the bonnet to check either. And you said you owned both ??????? As for brakes like I said D7E and F is mechanical you will still have brakes if you loose drive. D7G you will loose alot of your braking effort if you loose pump prime as they are hydraulically assisted. And no 'I' never ran out of drive or brakes on any machine because im smart enough to put my head under the bonnet and check fluid levels and fix anything if it goes wrong. And NO im not full of it either, I spent the first 10 years of my life fixing gear for the local cat dealer and even have a 'caterpillar service training passport' to prove it, so I DO know what makes things 'tick' Owning and driving dozers, yes I consider myself competent enough to hold my own. All my work is forestry roading, no pegs, make it up as you go along, just make sure trucks can climb it !, mainly on D7H and D6D. Maybe you do own a lot more machines than me; but you sure as hell never worked on them
Which D7 is this then? the decal on the tank says its a G, but its only got a 4 cyl engine in it.......so is it an E?
That looks like an early 1960's direct drive D7E Richardjw . What caught my eye was the flat fenders that don't have the 90 degree bend on the outer edge . Like this one www.machinerytrader.com/listingsdetail/detail.aspx?OHID=9814255 Then notice on this 1967 model it has the bent edge on the outer fender www.machinerytrader.com/listingsdetail/detail.aspx?OHID=9023699 That's my best guess .
No need to get nasty. Yet!! Question was!! "Hey Merv, how many times have you yourself had a D7 F/G lose transmission prime on a steep slope then have any trouble controlling it with the either brake??? Chum" Answer is!! Exactly as I thought Merv, The answer is no, you have not!!! Yes Merv I did use the wrong model number ,I did say D333 instead of D339, I certainly do know the difference! My mistake, methinks a case of to many numbers over to many years!! One could call into question your statement; Merv's quote "I spent the first 10 years of my life fixing gear for the local cat dealer and even have a caterpillar service training passport' to prove it, so I DO know what makes things tick" Now I would like to think that I am reasonable enough to know what you meant to say..?? [I spent the first 10 years of my WORKING LIFE fixing gear] Also I have the up most confidence that Caterpillar Tractor Company was not going to allow one of their dealership to employ an new born infant and then work this baby as a full time employee for the next 10 years!! (or until you're 10 birthday) A bad publicity move on Cat part, I would think!! LOL Nor at this point do I feel it is necessary to call you names or belittle you just because YOU MISSPOKE !!Or you disagree with me! But when people(you) make statements (especially about safety) that I know for a fact are very misleading (such as the quote below) then yes I will ask questions and usually(as in this case) will find out that that person is going on what he thinks or has been told and NOT what he knows to be a FACT!! Merv's Quote; D7F and Gs can get into trouble on slopes, if the oil level is low, especially climbing the trans can suck air; and there will be no go, no steering and not a lot of whoa either :eek more so on G, F is mechanical only brakes:. Also Merv; It may surprise you to know there are sometimes reasons that a crawler tractor can be in a position of being on a steep slope without power to the transmission system, some of which have little to do with the sticking ones head under a bonnet !!!!!! ?????? Remember Merv, It was not I who started throwing stones here just simply asking questions and while I am at it, how many early model D7F(suspect) transmissions have YOU ever tore all apart on the shop bench and rebuilt!...??? How many broken gears have YOU needed to replace...??? Have you had the opportunity to run a D7E side by side with a D7F building oil & gas field location's (pad's) and the roads to them, And then moving (towing/skidding) the drilling rig's skid loads and moving the trailer mounted loads with a tow dolly hooked to the D7..?? (some weighing over 90,000lbs) day after day, in every kind of condition Western Pennsylvanian and Western New York had to offer!! Steep side hill, Heavy hardwood timber, Steep road grades, Frozen ground, Soft bottom ground, Deep mud, Sometimes even easy good ground!! And today you may of been on an E and the next day you may of been on an F, some days you may split your day between them...??? All with angle blades, all with towing winches. We (I) have!!!! We(I) have spent thousands of hours doing this, Taxing these tractors for more than they were designed to do day after day after day!!!! We (I) also built have built hundreds of miles of logging roads and skid trails with D7's So Merv, admittedly I am and have previously been impressed with your mechanical knowledge that you have shared on this site, although on this topic of brakes and balance. I'll put my several personal experiences of recusing crippled equipment which required towing them up and then easing them down steep logging skid trails to the landing, and also coping with temporary loss of transmission pressure on steep slopes!! up against your; "Caterpillar service training passport'" all day long!! With me it thousand of time tested hours!! of day in and day out use!! And last but not least having the knowledge and experience to know whether a 7F has better balance than a 7E!! Not claiming as you did because;"the 7F would not climb as well, but yes probably backed up a bit better". it has better balance..????? Well I know your smarter than I, but doesn't that make the 7E nose heavy..??? Therefore a 7E not as well BALANCED!!! Just like I said!! I thought so!! And as far as the weak 7F transmission..?? Well all I can say is I am glad no one told us or our tractors (At least while we owned them) they had weak trannys because they sure as hell didn't know it!! And just kept plugging away giving us excellent service with very little down time day in and day out !!!! Chum..
Yep I would say you were right TD25c. Looks like a nice 47A model. I often think about getting another one to play with set up like that only maybe with a cable blade!!! I loved there unique engine sound, turbo whistle! Probably why I can't hear now!! BTW the head being off brings back some old memories!!! (not good) Chum..
Yep I would say you were right TD25c. Looks like a nice 47A model. I often think about getting another one to play with set up like that only maybe with a cable blade!!! I loved there unique engine sound, turbo whistle! Probably why I can't hear now!! BTW the head being off brings back some old memories!!! (not good) Chum..
Yeah Chum.. I thought that was an older 7E model . Yes the 4 cylinder in the 7E sure did have a distinctive sound about it .
Heres a pic from my cockpit chum; and yes I did a lot of the roading in this pic, show us one of yours ; and no im not being cheeky here:; and no its not a D7 :drinkup
Wow D6 Merv ! That is quite a view .Would Make for a great post card from New Zealand
Well im going to kiss the 7F goodbye and look for something else. I went to run it the other day and once we got it to start with a cotter pin and a lot of welding on the starter it all went down hill from there. The U/C is more like 20% with missing and seized rollers, the sprockets jumped when under load pushing snow and the tracks had seized links and lots of loose pads. There is no 3rd gear in either forward or reverse and when shifting between 1st and 2nd in either direction at lower rpm it hesitated then took off like dumping the clutch on a standard tranny, high rpm wasn't as bad but still jerky. The brakes were almost non existent and when they did grab they would stick and not want to release right away. Other than that the engine did run good and the hydraulics seemed to work good but I think that machine is more for parts or scrap unfortunately. I am turning my attention towards a couple D6C's I have found with hopes of a lot better results. Thanks for the info on the 7 from everyone and ill see you when I start asking questions on the 6s.
At least it was an easy decision ironage . Good luck in your future search for the D6.
Some of the toy's the luckiest guy in the world had/has in his toy box to play with!! Merv, here is a little look of what matters and can be seen in my world. I don't have many pictures of my youth until my mid 30's. Please enjoy a look at some of our equipment over the years. I know I sure enjoyed looking them over again!! BTW, we start them a little early on this side of the pond!!LOL LOL Chum.. http://s1200.photobucket.com/user/dozerduff2010/library/Chums world
I own a d7F its been a good machine. Like any piece of equipment common sense while using it with good maintence goes a long way. Mine is a former military machine with a 3 shank ripper semi u blade and power shift
Nice photo album Chum Duffy:thumbsup I enjoyed looking through all the different brand machines & vintage dozers .
Thank you TD25C! The pictures are nearly all taken by my wife Ronda the wonderful woman who has put up with me since 1984!! I regret I do not have a lot of pictures from my mid sixty to mid ninety years in this photo bucket. I think I just did not worry about or readily carry the photo equipment to take pictures during that time frame sadly! There would be a lot of oil and gas felid construction and rig moving pictures also forestry road building pictures including the use of the 15 to 18 yard Allis Chalmers and Cat two wheel drive rubber tire scrapers, and also the International 433's/444 and Terex TS 14 double barrel scrapers we were running then. We also had a Terex 82-20 crawler dozer with a angle blade and a Cargo 80 winch which was a very good dozer and we all liked it very well. I would say size wise it was between the D6C/D's or TD15C's and the D7E/F's, or TD20C all with angle blades and winches that we were also running at that time, also the International's 15C and 20C could/ would out work the Cats 6C/D and 7E/F by a fair margin. We also had a pair of D8H-46A's and rented TD25C's as needed. Again the International 25C's would easily out work the Cat 8H's however I will point the 25C's were a bit bigger!! Don't get me wrong I am not knocking the cats they were good tractors and I liked them very much however they were not the last or only answer in bulldozers!! We also had 4 oil/gas field 5 axel winch trucks and a tandem rollback we moved rig's with that sadly I have very few picture's of. It was not uncommon to expect an 80 hour week back then and at times we worked over a 100 hours a week, week after week!! I don't want to seem like I am bragging or complaining just saying spending all this time doing what I love to do and earning a decent living for and with my family has made me one of the luckiest guys in the world!! I truly owe this all to my GOD for giving me the strength and dedication!! My Mom and Dad for teaching me how and when to work!! MY Brothers and Sisters for always being there when I need help the most!! My children for giving me the reason to continue on and who are going to have to take care of me in the manner in which I am going to become accustom to $$$, soon!!! LOL LOL !! My best buddy Michael, my little brother and constant business partner from the day he was born until June 14 2012 when he died!! But mostly to my loving wife Ronda!! Who has done an excellent job raising our beautiful children always seeing that our needs were taken care of!! Unselfishly allowing me the time needed to focus on our companies needs!! Always being my own personal cheerleader!! Quietly doing her best to fix the mistakes I have made along the way!! Keeping me focused on what has truly been important in our lives!! And always making me think it was me that was doing it all, when in fact most of the time it was really her!!! All while still being able to make my heart skip a beat even after 30 years!!! Me lucky..?? No I'd say truly Blessed.... Chum..
Very well put Chum ! A lot of truth in that . I really enjoy the dozer jobs ,be it clearing ,road building , Pond/Lake . At times I feel like a paid tourist on vacation while operating as I like so much . Just something that gets in your blood I reckon .
I'm looking at a really nice D7F online with serial number 77E3072 From the "94N" serial number discussion above, I can't tell if this is one of the problem machines vs a good one. It's advertised as a former military dozer if that helps Appreciate guidance from anyone with knowledge on this. Thx.
77E is the blade S/N. If it is ex-military the tractor S/N will most probably be 61G-something. That's the number you really need. AFAIK a 61G is the equivalent of a 94N machine prior to 94N5191. That would be prior to the transmission update and a number of other mods. EDIT: This confirms whatr I was thinking.
that's helpful Nige -- the seller went and found the REAL serial # which is 61G579 based on that, would this be a tractor to stay away from?
I wouldn't like to express an opinion one way or the other. With a tractor that age a lot will depend on its physical condition rather than the S/N. From the information that's out there the 94N-prefix tractors from 94N5192-Up were preferred over the earlier series 94N1-5191 mainly because of the transmission upgrade and later with the change from the D333C engine to a 3306. Whether that makes the earlier ones a "bad" machine I'm not sure. Here are a couple of threads regarding D7F tractors that might help you.
Military tractors are generally lightly worked. But the earliest D7F's with the D7E transmission had harsh transmission gearshifting, particularly when carrying out directional changes at full throttle. Cat always claimed their powershift transmissions were able to be changed between any gear, and either direction, at full engine RPM's. But the earlier D7F transmissions gave repeated trouble under heavy working conditions, thanks to a lack of a transmission modulating valve. A transmission modulating valve temporarily drops the transmission oil pressure to the clutch packs, to ensure a smoother change (especially a directional change) when the engine is left at full throttle during directional gear changes. When Cat started to realise the early D7F transmissions were proving troublesome under hard operating conditions, they redesigned the transmission control valve to include a modulating valve. This was a major engineering change involving a new transmission valve body and lines that cannot be retrofitted. I can't recall the exact D7F serial number when the transmission modulating valve was introduced, it's been over 50 years since I bought my first D7F, and nearly 30 years since I sold my last one. The fitment of the transmission modulating valve to the earlier D7F transmissions assisted in reducing transmission change shock-loading, but the change shortly after, to the later 2P model transmission from the D6C was the biggest transmission improvement ever to the D7F, and this then made them a very reliable tractor. If you're not doing heavy contracting work on a consistent basis, and you decelerate the engine RPM's when changing direction, the early D7F transmission will more than likely give you a satisfactory reliability level. I owned 3 x D7F's from the early 1970's, two with the very early transmission, and one with the later transmission, and they were all worked very hard on contract work, pushing 2000-3000 yds a day, all day, every day, ripping very hard rock regularly, and with a range of operators, some of whom were not the kindest to the tractors. The tractor all did around 2,500-3000 hrs annually each. The two machines with the early model transmission gave regular transmission problems, the major problems being related to excessive shock loading in the transmission when changing direction, and the second source of problems being the low operating speed of the transmission, which put high torque through the planetary gears and their needle roller bearings, which all suffered from premature wear, thanks to the high loading. A transmission overhaul for the early transmission nearly always involves complete replacement of all the planetary gears and shafts and needle rollers - an expensive exercise, particularly when you add in clutch plates, all the bearings, and any other damaged gears. The early D7F transmission design is such, that the needle rollers run directly on the planetary gear inside surfaces, and directly on the planetary shafts - there are no replaceable needle roller races, it's a relatively poor design that relies on bearing hardness quality for the planetary gears and shafts. But the gears and shafts hardness always seemed to be less than regular bearing race hardness. We always operated the tractors at full throttle with no engine deceleration on directional changes, because this is what Cat told us they were capable of doing constantly. We found otherwise with the early D7F. Also, we preferred constant full throttle operation, as regular deceleration on directional changes increases fuel consumption.
so the one I'm looking at has the 3306 which would suggest it's one of the later models produced; i can give the Cat guys a call with the military serial number but can anyone on here tell me what the upgraded transmission serial number would be?
The upgraded transmission has a 2P arrangement # and the tag should be located on the top of the transmission. The later model transmission is only 2/3rds the physical size of the early transmission.
The 61G machine is not in the Cat online system, only the reference to tell whoever is looking to refer to the 94N1-5191 S/N range for parts and service information. Based on the information I have seen all 61G machines were originally built with a D333C engine and the “old style” transmission, just the same as all 94N machines up to 94N5191 were. The engine Serial Number will confirm what model of engine is in it. If it is 61G579 the same as the tractor it is a D333C. If it is a 3306 the engine S/N will start with 3N. The easiest way to tell what transmission it has is to take a look under the floor. One of the threads I linked has an image of the 2P transmission.
This is what the "old-style" 9S-5250 Transmission Arrgt, as fitted to 94N machines from first built up to 5191 (and I think to all 61G machines), looks like. This is the "D6 style" 2P-3663 Transmission Arrgt fitted to D7F machines from 94N5192-Up. Physically it is only about two-thirds of the size of the transmission fitted to earlier D7F machines.
the seller found that the transmission was rebuilt by Ziegler in 2002 which is good news but also found a "5S" casting number on the transmission case. that is obviously different than 2P so still not sure whether they rebuilt the old or replaced with the updated any additional thoughts??
Whether the transmission is 9S-5250 or 2P-3663 that is the number for the complete assembly and should appear on a data plate somewhere on the side of the transnmission case just below the top cover. The plate will probably also have "Arrgt Number" or something similar on it. Can you get the seller to send you a photo of the transmission (not just the "5S" casting mark) taken from at least a couple of feet away and post it here.?
a few pics
do these help
The 5R-862 (5R-0862) on the tag with the green paint is the Transmission Arrangement tag. Apparently the military 61G D7F used a slightly different Arrgt to the early 94N D7F. The differences between the 5R-0862 and 9S-5250 are a different control valve and some minor differences in a shaft, and a couple of clutch plate & friction disc Part Numbers. To all intents & purposes the transmission in the D7F S/N 61G597 that you are looking at is an "old style" D7F transmission IMHO.
really appreciate all the research and guidance Nige!
I learned something as well. I never realized up till now that the military transmission was different in some respects to the "civilian equivalent" transmission. Now the challenge is to find out why...!!
So they can charge the military a lot more. Seems anything for the military always has an outrageous price. A $25 shovel for the military suddenly becomes a $50 shovel to meet military spec's.