ACMOC
Login
ACMOC
Difference between Cat 12F / 12G

Difference between Cat 12F / 12G

Showing 1 to 10 of 15 results
1
1941D4DOZERBOY
Topic Author
Offline
Send a private message to 1941D4DOZERBOY
Posts: 42
Thank you received: 0
What’s the difference between a Cat 12F and a 12G?? I’m looking to buy a 12F this weekend and would like to know more about it. Thanks [attachment=53667]894C06C0-0128-47EF-B11C-B991F58D3A84.jpg[/attachment]
Attachment
Please log in or create an account to join the conversation.
Sun, Apr 28, 2019 12:23 PM
Deas Plant.
Offline
Member
Send a private message to Deas Plant.
Location: Currently - DowNunda.
Posts: 6,646
Thank you received: 12
Hi, 1941D4DOZERBOY.
The grader in your photo is NOT a Cat 12F series grader, regardless of what stickers it happens to be wearing. Atta guess, I would put it at about a 9K series, WW2 era. That said, it doesn't look to be in bad shape for its age.

If you look at the machine in your photo, you may notice that the blade lift arms project forward from the front face of the cab. The most noticeable difference between that machine and 12F is that the blade lift arms on the 12F project rearward from the front of the main frame. The control box in the cab was also hydraulic boosted controls which made them MUCH more user friendly that the unit in your photo.

The 12G was/is a whole nuther story. It was a part of the first line-up of Cat graders to go full hydraulic - hydraulic EVERYTHING - including articulated back end steering. Another difference is that there is NO differential in the machine in your photo. It is a totally locked up back end with all 4 wheels driving ALL the time. The 12G and all the G series and the H and M series as well all have a differential with an electrically operated diff lock.

Just my 0.02.

You have a wonderful day. Best wishes. Deas Plant.

Please log in or create an account to join the conversation.
Sun, Apr 28, 2019 12:54 PM
ccjersey
Offline
Send a private message to ccjersey
Posts: 4,422
Thank you received: 0
8T series most likely........there were lots more of them made. Could be a 70D or 71D which came after, still with the D318 engine and oil clutch........cant remember which was pony start and which was direct electric start. Late 8T also have oil clutch using engine oil pumped into it and returned by flywheel slinging it back into engine.

Serial number would help.
D2-5J's, D6-9U's, D318 and D333 power units, 12E-99E grader, 922B & 944A wheel loaders, D330C generator set, DW20 water tanker and a bunch of Jersey cows to take care of in my spare time😄
Please log in or create an account to join the conversation.
Sun, Apr 28, 2019 7:22 PM
1941D4DOZERBOY
Topic Author
Offline
Send a private message to 1941D4DOZERBOY
Posts: 42
Thank you received: 0
Reply to ccjersey:
8T series most likely........there were lots more of them made. Could be a 70D or 71D which came after, still with the D318 engine and oil clutch........cant remember which was pony start and which was direct electric start. Late 8T also have oil clutch using engine oil pumped into it and returned by flywheel slinging it back into engine.

Serial number would help.
Thanks for the help and info on here, I don’t have the serial of it yet. Here are more pictures of it. It has a 12F sticker on the cab. Also the owner says it’s a 1959. I still would like to know what the difference is between a 12G and 12F is. I also thought that a 12F had hydraulic over mechanical. I don’t think this does.

[attachment=53668]DBF7D24E-EB62-43E3-955C-218EE97EDB91.jpg[/attachment][attachment=53669]9D3F46AC-FC37-4F4A-944F-C72435F45677.jpg[/attachment][attachment=53670]0D4DCDDD-BE19-4E4C-861B-919824006062.jpeg[/attachment][attachment=53671]AB4FF6C5-F510-49AC-8739-575BB4137559.jpg[/attachment][attachment=53672]64788925-4A9C-4693-98E9-027AA7951815.jpg[/attachment]
Attachment
Attachment
Attachment
Attachment
Attachment
Please log in or create an account to join the conversation.
Sun, Apr 28, 2019 8:57 PM
Deas Plant.
Offline
Member
Send a private message to Deas Plant.
Location: Currently - DowNunda.
Posts: 6,646
Thank you received: 12
Reply to 1941D4DOZERBOY:
Thanks for the help and info on here, I don’t have the serial of it yet. Here are more pictures of it. It has a 12F sticker on the cab. Also the owner says it’s a 1959. I still would like to know what the difference is between a 12G and 12F is. I also thought that a 12F had hydraulic over mechanical. I don’t think this does.

[attachment=53668]DBF7D24E-EB62-43E3-955C-218EE97EDB91.jpg[/attachment][attachment=53669]9D3F46AC-FC37-4F4A-944F-C72435F45677.jpg[/attachment][attachment=53670]0D4DCDDD-BE19-4E4C-861B-919824006062.jpeg[/attachment][attachment=53671]AB4FF6C5-F510-49AC-8739-575BB4137559.jpg[/attachment][attachment=53672]64788925-4A9C-4693-98E9-027AA7951815.jpg[/attachment]
Attachment
Attachment
Attachment
Attachment
Attachment
Hi, 1941D4DOZERBOY.
It may be as late as an 8T but I seriously doubt ccjersey's suggestion that it might be a 70D/71D as I think they had gone to having the instruments mounted in a panel beside the seat instead of in the box on the pipe column to the right of the control box like yours has - see photo 3 of your last post.

The 12F DID have the hydraulic over mechanical controls - hydraulic boosted - but the most noticeable difference from a distance was the blade lift gears being mounted on the front end of the main frame instead of being on the front of the cab.

If the current owner is selling it as a 1959 model and priced accordingly, methinks you ought to make sure what model it REALLY is and what the market value of that model is before laying down your 'hard-earned' - - - - - - IF you haven't already laid it down. If you can post the serial # here, somebody will likely come back pretty quick with a build year for you.

Re the differences between the 12F and the 12G, I thought...................................... See my earlier post.

On top of that, and in more detail, the 12Gs had hydraulic rams for the blade lift, braking on all four rear wheels, hydraulic side shift for the circle, hydraulic lock-pinned saddle frame carrying the lift rams and side shift ram to allow complete in-seat side shifting of the blade to one side or the other for cutting slopes, hydraulic circle reverse and hydraulic leaning front wheels. It also had the 'piano keyboard' controls which shared a control column with the steering wheel, said column being movable for and aft to suit operator reach and to allow easy access to and from the seat.

Just my 0.02.

You have a wonderful day. Best wishes. Deas Plant.

Please log in or create an account to join the conversation.
Sun, Apr 28, 2019 10:03 PM
Old Magnet
Offline
Send a private message to Old Magnet
Posts: 16,695
Thank you received: 17
Reply to Deas Plant.:
Hi, 1941D4DOZERBOY.
It may be as late as an 8T but I seriously doubt ccjersey's suggestion that it might be a 70D/71D as I think they had gone to having the instruments mounted in a panel beside the seat instead of in the box on the pipe column to the right of the control box like yours has - see photo 3 of your last post.

The 12F DID have the hydraulic over mechanical controls - hydraulic boosted - but the most noticeable difference from a distance was the blade lift gears being mounted on the front end of the main frame instead of being on the front of the cab.

If the current owner is selling it as a 1959 model and priced accordingly, methinks you ought to make sure what model it REALLY is and what the market value of that model is before laying down your 'hard-earned' - - - - - - IF you haven't already laid it down. If you can post the serial # here, somebody will likely come back pretty quick with a build year for you.

Re the differences between the 12F and the 12G, I thought...................................... See my earlier post.

On top of that, and in more detail, the 12Gs had hydraulic rams for the blade lift, braking on all four rear wheels, hydraulic side shift for the circle, hydraulic lock-pinned saddle frame carrying the lift rams and side shift ram to allow complete in-seat side shifting of the blade to one side or the other for cutting slopes, hydraulic circle reverse and hydraulic leaning front wheels. It also had the 'piano keyboard' controls which shared a control column with the steering wheel, said column being movable for and aft to suit operator reach and to allow easy access to and from the seat.

Just my 0.02.
Worlds apart!!! to begin with the 12F (say 13Kxxxx) will have a D333c engine.
The 12G (say 61Mxxxx) will have the 3306 engine, direct drive powershift, articulated frame, all hydraulic controls, oil disc brakes and all the modern features.
Your looking at one of the D318 engine models, totally different affair.
Please log in or create an account to join the conversation.
Sun, Apr 28, 2019 10:25 PM
ironman3406
Offline
Chapter Leader
Chapter Twenty Seven
Send a private message to ironman3406
Posts: 252
Thank you received: 0
Reply to Old Magnet:
Worlds apart!!! to begin with the 12F (say 13Kxxxx) will have a D333c engine.
The 12G (say 61Mxxxx) will have the 3306 engine, direct drive powershift, articulated frame, all hydraulic controls, oil disc brakes and all the modern features.
Your looking at one of the D318 engine models, totally different affair.
Hey 1941D4DOZERBOY,

Ive attached 3 pictures comparing the grader that you are looking at, to a 12F and a 12G.
Red circles are showing the differences of the drive gears and the shafts that a few guys have made reference too. Rear driven, vs front driven.
The machine you are looking at is most definitely not a 12F, as i'm sure you have read more than once in this thread.


12F:
Caterpillar D333 six cylinder diesel engine
6F-4R gears, direct drive.
Hydraulic over manual control with Hydraulic assist
Rigid frame
14' moldboard
Side shift
Optional 2' left blade extension
30,925 lbs. base operating weigh

12G: Total redesign model
Caterpillar 3306 six cylinder diesel engine
6F-6R gears, powershift.
Fully hydraulic controls for all blade functions
Articulating frame
14' moldboard with optional 2' extension
Hydraulic side shift
29,525 lbs operating weight

Hope this helps you out
Cheers
Nate
Attachment
Attachment
Attachment
Please log in or create an account to join the conversation.
Mon, Apr 29, 2019 6:20 AM
1941D4DOZERBOY
Topic Author
Offline
Send a private message to 1941D4DOZERBOY
Posts: 42
Thank you received: 0
Reply to ironman3406:
Hey 1941D4DOZERBOY,

Ive attached 3 pictures comparing the grader that you are looking at, to a 12F and a 12G.
Red circles are showing the differences of the drive gears and the shafts that a few guys have made reference too. Rear driven, vs front driven.
The machine you are looking at is most definitely not a 12F, as i'm sure you have read more than once in this thread.


12F:
Caterpillar D333 six cylinder diesel engine
6F-4R gears, direct drive.
Hydraulic over manual control with Hydraulic assist
Rigid frame
14' moldboard
Side shift
Optional 2' left blade extension
30,925 lbs. base operating weigh

12G: Total redesign model
Caterpillar 3306 six cylinder diesel engine
6F-6R gears, powershift.
Fully hydraulic controls for all blade functions
Articulating frame
14' moldboard with optional 2' extension
Hydraulic side shift
29,525 lbs operating weight

Hope this helps you out
Cheers
Nate
Attachment
Attachment
Attachment
Thanks for the help gentlemen. Anyone think this might be a cat 112?? Where can I find a list of serial identification numbers for the years of grader? Or can you tell me what engine this grader has?? Thanks!! I’m very greatful!!!
Please log in or create an account to join the conversation.
Tue, Apr 30, 2019 8:01 AM
1941D4DOZERBOY
Topic Author
Offline
Send a private message to 1941D4DOZERBOY
Posts: 42
Thank you received: 0
Reply to 1941D4DOZERBOY:
Thanks for the help gentlemen. Anyone think this might be a cat 112?? Where can I find a list of serial identification numbers for the years of grader? Or can you tell me what engine this grader has?? Thanks!! I’m very greatful!!!
I’m thinking it could be a 112F. Check out this video.

https://youtu.be/SlQiNgZw59A
Please log in or create an account to join the conversation.
Tue, Apr 30, 2019 8:15 AM
oldbeek
Offline
Member
Send a private message to oldbeek
Posts: 781
Thank you received: 0
Reply to 1941D4DOZERBOY:
I’m thinking it could be a 112F. Check out this video.

https://youtu.be/SlQiNgZw59A
Get a serial #. Every picture there is identical to my 1949 8T cat 12 right down to the air filter. It has a 318 engine, 6 cylinder. A 112 would be a 4 cylinder. The price depends on condition. The big gears on the front of the cab that lift the blade will tell a story. If they are in fair to good shape, you will be able to push the levers forward and lift the front end off the ground. If they are severely warn, the levers will kick the hell out of you. They can be turned to a new wear spot but that can not be recognized from the outside. Lift arm ends another place to look. Any slop? New they had a shim pack at the ball. Any shim pack left? How much wear on the circle gears and top and bottom of the circle. Lift front off ground. King pin and wheel bearing slop. Old 12s are good old machines and don't have hydraulic pumps and controls to go bad which can get expensive. Big farms in CA keep them around to straighten up their roads. New China tires are about $600 ea. Watching a you-tube vid, 1952 had pony controls inside the cab. This one they are all outside. 1948 and earlier had a different engine also.
Please log in or create an account to join the conversation.
Tue, Apr 30, 2019 8:55 AM
oldbeek
Offline
Member
Send a private message to oldbeek
Posts: 781
Thank you received: 0
Reply to oldbeek:
Get a serial #. Every picture there is identical to my 1949 8T cat 12 right down to the air filter. It has a 318 engine, 6 cylinder. A 112 would be a 4 cylinder. The price depends on condition. The big gears on the front of the cab that lift the blade will tell a story. If they are in fair to good shape, you will be able to push the levers forward and lift the front end off the ground. If they are severely warn, the levers will kick the hell out of you. They can be turned to a new wear spot but that can not be recognized from the outside. Lift arm ends another place to look. Any slop? New they had a shim pack at the ball. Any shim pack left? How much wear on the circle gears and top and bottom of the circle. Lift front off ground. King pin and wheel bearing slop. Old 12s are good old machines and don't have hydraulic pumps and controls to go bad which can get expensive. Big farms in CA keep them around to straighten up their roads. New China tires are about $600 ea. Watching a you-tube vid, 1952 had pony controls inside the cab. This one they are all outside. 1948 and earlier had a different engine also.
Deas, there was an engineer that bought a 120g with no differential to lower the bid price. He bought it that way under protest by CAT. He also had rippers installed on the rear. ( more rear weight) It was bought for road dept use. Every time it was used to lay new asphalt, it would blow a wheel planetary. When I took over the shop, I wanted to put a differential in it. He would not admit his mistake. I had my machinest groove the final axles. Made them the sheer spots. They were easy to RandR. After the guy finally retired, CAT gave me a good deal on replacing the spool for a differential.
Please log in or create an account to join the conversation.
Tue, Apr 30, 2019 9:11 AM
Showing 1 to 10 of 15 results
1
YouTube Video Placeholder

Follow Us on Social Media

Our channel highlights machines from the earliest Holt and Best track-type tractors, equipment from the start of Caterpillar in 1925, up to units built in the mid-1960s.

Upcoming Events

Veerkamp Open House 2025

Chapter Fifteen

| Placerville, CA

Stradsett Park Vintage Rally

Chapter Two

| Stradsett, Nr Downham Market. Norfolk PE33 9HA UK

Chapter 2 The Link Club's AGM

Chapter Two

| Faulkner Farm, West Drove, Wisbech, Cambridgeshire, PE14 7DP, UK
View Calendar
ACMOC

Antique Caterpillar
Machinery Owners Club

1115 Madison St NE # 1117
Salem, OR 97301

[email protected]

Terms & Privacy
Website developed by AdCo

Testimonials

"I became a member recently because the wealth of knowledge here is priceless." 
-Chris R

Join Today!