D7F serial number

[1bigtime379]

I am looking for a cat for my acreage and there is a D7F for sale that is local to me
The fellow that owns it told me it’s a Japanese machine. Serial number 92E1533

I am aware of the transmission problems in the earlier D7F’s. I am curious if this machine came with the better transmission or the older D7E transmission. What should I look for when I go look at the cat in person?

 

[Nige]

What should I look for when I go look at the cat in person?

You will need to lift up the floor plate in the cab. If it has the transmission derived from the D7E it will fill the space between the frame rails almost entirely. If it is the later transmission derived from the D6 you will almost be able to have a dance in the space around it.

92E is a Japanese-built tractor equivalent to a US-built 94N-prefix tractor.

From the information I have all 92E tractors up to around S/N 1750 were fitted with the D7E-derived transmission.

 

[1bigtime379]

You will need to lift up the floor plate in the cab. If it has the transmission derived from the D7E it will fill the space between the frame rails almost entirely. If it is the later transmission derived from the D6 you will almost be able to have a dance in the space around it.

92E is a Japanese-built tractor equivalent to a US-built 94N-prefix tractor.

From the information I have all 92E tractors up to around S/N 1750 were fitted with the D7E-derived transmission.

Perfect thank you, that is extremely helpful

 

[.RC.]

D333 engine as well.

92E1752 up is the changeover S/N to the 2P transmission arrangement.

 

[1bigtime379]

D333 engine as well.

92E1752 up is the changeover S/N to the 2P transmission arrangement.

D333 engine as well.

92E1752 up is the changeover S/N to the 2P transmission arrangement.

Is the D333 something to stay away from? I mean I am expecting to do some work as it is a 50 year old machine.
The undercarriage is in excellent condition which makes this dozer priced right for me

 

[Nige]

We’ve had this discussion before. If you are not working the machine hard 60-70 hours a week like a contractor would then IMHO the D333 engine/D7E transmission combination should work just fine. Yes the 3306 engine and the new-style transmission were an improvement but that does not make the previous setup something to shy away from.

 

[FWD]

I agree with the fact that the OP is not going to be hard on it, but who knows what the previous owner has done with it.
FWD

 

[Nige]

I agree with the fact that the OP is not going to be hard on it, but who knows what the previous owner has done with it.

I agree. A complete unknown. The only two things I am taking into consideration are the OP’s comments “I mean I am expecting to do some work as it is a 50 year old machine” and “The undercarriage is in excellent condition which makes this dozer priced right for me.” Most dozers the age of this one usually have the undercarriage hanging in tatters……..

 

[.RC.]

What I find straight up bizarre is the magnitude of questions about the D7F and the lack of questions about the D7G, when the F series was only made for a handful of years.

Surely there must be heaps more G's for sale then F's? Just by weight of manufactured units alone.

 

[tkfarms]

What I find straight up bizarre is the magnitude of questions about the D7F and the lack of questions about the D7G, when the F series was only made for a handful of years.

Surely there must be heaps more G's for sale then F's? Just by weight of manufactured units alone.

There have been tons of D7G for sale in alberta this spring and summer.... I found it funny...seems everyone here decided to sell them this year.

 

[Nige]

What I find straight up bizarre is the magnitude of questions about the D7F and the lack of questions about the D7G, when the F series was only made for a handful of years.

I suspect it is all down to the somewhat "chequered history" in people's minds regarding the D7F. All the talk about early/late transmissions plus the upgrade from the D333C to the 3306 with precups then a 3306 with direct injection has people asking all sorts of questions. Sometimes it appears that the only definitive information in respect of all those differences is here on this forum.

In comparison all the various iterations of D7G/D7G Series II were pretty much the same from the time the model was first introduced until the time it was discontinued for the first of the high-drives. For example the same 9P-5382 Transmission Arrgt was used in every D7G tractor built.

 

[LCA078]

D333 engine as well.

92E1752 up is the changeover S/N to the 2P transmission arrangement.

You should see a tag on the transmission that looks like one in the pic I attached. I have a D7F with the "old" transmission. Sounds like the "new" transmission will start with a 2P.

What I find straight up bizarre is the magnitude of questions about the D7F and the lack of questions about the D7G, when the F series was only made for a handful of years.

Surely there must be heaps more G's for sale then F's? Just by weight of manufactured units alone.

My guess is that most of the regular D7G's have been retired whereas a lot of the D7F's (the military ones) went through rebuilds, sat unused for decades, then hit the auctions as low hour machines in the past decade after units starting turning in old equipment from the wars. And there's been quite the number of ex-military D7F's at auction in the past few years. I assume that's generating all the questions

 

[Nige]

You should see a tag on the transmission that looks like one the pic. I have a D7F with the "old" transmission. Sounds like the "new" transmission will start with a 2P.

Only military 61G-prefix machines use the 5R-0862 Transmission Arrgt.
A low S/N 94N with the "early" D7E-derived transmission will be a 9S-5250 Arrgt.
A high S/N 94N with the "late" D6C-derived transmission will be a 2P-3670 Arrgt.

To go from a 5R-0862 to a 9S-5250 involves a change of Planetary Transmission Group and a different Hyd Control Valve. There are significant differences in both of those components but I have no idea for the reason behind that.

 

[Welder Dave]

I think the D7G were regarded as one of the best Cat dozers ever made and thus were a lot less problematic. Cat may have realized they missed the mark with the latter D7F models.

 

[LCA078]

Only military 61G-prefix machines use the 5R-0862 Transmission Arrgt.
A low S/N 94N with the "early" D7E-derived transmission will be a 9S-5250 Arrgt.
A high S/N 94N with the "late" D6C-derived transmission will be a 2P-3670 Arrgt.

To go from a 5R-0862 to a 9S-5250 involves a change of Planetary Transmission Group and a different Hyd Control Valve. There are significant differences in both of those components but I have no idea for the reason behind that.

Nige- Your observation of differences in the planetary from the 5R to the 9S transmission makes me wonder if there is a deliberate difference in gear ratios across the drive system? Maybe the military realized the weakness of the 9S and requested better ratios that level the stress better across components in the older transmission system? I'm just completely guessing as I assume the rpms of the D333 and 3306 are fairly close in this application.

 

[Nige]

Maybe the military realized the weakness of the 9S and requested better ratios that level the stress better across components in the older transmission system?

Don’t credit the military with that much intelligence……

Let’s face it they hung on to their D7Fs far too long in the first place and then piled insult on injury by refurbing them so that when they finally came on the market they were 30+ year-old technology. The only people who got anything out of it were those like you who managed to buy at the right price.

 

[LCA078]

Haha- maybe so but it's also quite possible that Cat offered an improved gear solution since they originally sold a "weak" design to the military. I can easily see the military scrapping it's entire fleet of D7F's to be replaced by JD's because of an abnormally high transmission failure rate. Cat knows this is quite possible and thus offered a solution through SLEP that improved the reliability while also keeping acquisition costs low for the military. I don't know of a larger "fleet" of heavy equipment owned by one owner than the fleets in the military so there is substantial influence on the Cats, JDs, Boeings, AMGs, etc. to offer unique solutions.

Again, I'm only guessing and have no factual information to back any of this up. Maybe it's just the optimist in me thinking the military did a few things right.

 

[Nige]

Cat knows this is quite possible and thus offered a solution through SLEP that improved the reliability

Did the SLEP program actually address the inherent design issues with the transmission.? I wasn’t aware that it did.

 

[LCA078]

Did the SLEP program actually address the inherent design issues with the transmission.? I wasn’t aware that it did.

I have no idea if it the SLEP program addressed transmission design issues or not. I'm only speculating that the SLEP program probably wouldn't stuff different gears into the transmission unless there was some sort of upgrade or fix. Probably the only way to tell is compare the differences part by part and see if there is a change in tooth ratios.

 

[pittsburgh cat man]

We did quite a few of those Cat would send all the parts. I can’t remember much for transmission other than bearings seals and discs