My brother and I helped Dad with a brake job on the tractor. Each axle weighs about 500lb, and the brake discs are up next to the differential, not out at the wheel hub. So, to change them, you’ve got to remove each axle from the tractor’s central case. Tractors are far simpler than automobiles, but they are a lot heavier.
Pictures for your enjoyment.
Awriight! Inboard disk brakes! Jaguar’d be so proud!
Wonder why they do that on a tractor?
I figure it’s got nothing to do with unsprung weight, but maybe I’m wrong…
Edit: Ah. I see now. Thanks to the Canadian Redneck, eh.
Yup, gotta have space for your balls. 
As a fun factoid, the end where the tire goes on is actually a planetary gear set which gears down the main drive shaft RPM for better torque.
These are amazingly fun and useful little machines.
Yeah buddy.
I actually was just looking into that, and pondering asking, but I finally found a diagram with the layout.
http://www.agriline.co.za/tractorparts/series200/265/differential.php
So…
Is there any “gear changes” that go on with those gears, as far as “shifting” or the like, or are they always doing the same thing?
The fixed planetary in the hub can’t be changed.
Up in the driver’s seat, you’ve got H-N-L and then 1-2-3-R, plus another High-Low lever. That gives you twelve forward ratios and four reverse ratios.
http://www.tractordata.com/farm-tractors/000/7/4/746-massey-ferguson-165-transmission.html
Most industrial gear with planetary hubs have no selectable gearing at the planetary, other than some will have a cap on the outside that can be flipped over and screwed on backwards that disconnects the input shaft for shipping.
Tractors are generally built with huge service factors compared to cars and designed to withstand considerable shock load as your plow or front loader catches a massive buried rock.
The brakes are usually individually selectable, so they can be used to enhance steering, or feathered to keep the wheel with less traction from spinning, and allow for a lot more total pull. Though differential lock pedals are a more common solution on newer tractors, they still retain the ability to brake one side only for enhancing turns.
That’s so cool.
I love tractors (well, of course, they have an engine!).
I love going to the small-town festivals (you know, "watermelon festival, peach festival, harvest festival, pumpkin festival, etc.) and see the old tractors putting around. I can watch yootoob for hours with the tractor shows. I think I MAY actually like that better than the car shows, but it’s close. : Tractors tend to have less chrome trailer queens. Too bad I know so little ABOUT tractors. We were too poor for one when I lived in farm country… 
I will add, I have found myself on a 30 HP tractor, stuck in a gully, spinning one front wheel, and the opposite rear wheel. I think I wound up using both the differential lock and some push from the front loader to get myself back out.
Also keeps brakes out of the mud mch more. On Jaguar probably more to do with unsprung weight and suspension design.
My 1965 Land Rover Pick up had a five brake drums, emergency brake at the rear of the transfer case at the drive shaft. When engaged it locked all four wheels. FWD all the time.
US military hummers(buckets oh shite) have inboard brakes as well - all well and dandy until a CV joint brakes and you have zero braking on that corner.
I’ve done my share of inboard Jag brakes-lots of labor…
That’s 4WD in new money.
http://www.consumerreports.org/cro/2012/12/2wd-awd-or-4wd-how-much-traction-do-you-need/index.htm
And then there is the UNIMOG…nothing “automatic” (the way driving should be)
That last bit about awd not being better in cornering - by consumers report is incorrect - but then again it is “consumer report”
Thanks for posting the MF repair!
I’ll confess not having read the report. I just was using it to illustrate popular, well-published usage of AWD, RWD, FWD, and 4WD.
Glad you enjoyed it! I enjoy working on large equipment far more than compact cars, as it is easier to get at the bolts.
I believe that in conjunction with traction control and stability control AWD is significantly better than alternatives… but without it I wouldn’t expect much improvement in adverse conditions…
Edit: Thinking about cornering as in racing, I could also see where it would be a big improvement over a RWD car, but not FWD… since you are probably already pushing against the traction limit in the back that is keeping you from swinging out, there’s not much extra torque you could put to the road and expect it not to lose traction faster I would think.
That’s just a guess though.
Ur Ur-Quattro has a response.
To steer this beast back to topic, Massey Ferguson builds nice stuff.
Wow! Very interesting! Thank you for sharing! I would have loved to have loved to have checked out the tractor live!
Unlike most modern 4WD that have gearbox option of 2 or 4 wheel drive or hubs you could unlock so they’ll spin free, Rover had only hi-lo gear band selection, all wheels drove all the time.
I probably caused the confusion, FWD at that time (when dinosaurs roamed the Earth) meant 4 Wheel Drive not Front Wheel Drive.
