s 373d 4wd not engaging

dlrepic · Dec 19, 2014

Update - I lifted the front tire and it spins freely and independently with it in gear and 4 wheel drive engaged, so this points to? - so next step?
I assume this brings me back to the drive shaft and the gears not alligning properly in the gear box?
Thanks
Danielle

Ilikeurtractor · Dec 21, 2014

It should NOT spin freely. Therefor there is a problem in the front differential or one of the final drive assemblies. Was the front wheel you were not spinning on the ground and not rotating while you were doing this?

dlrepic · Dec 25, 2014

Morning tractorbynet friends - Merry Christmas:grinch:

Ilikeurtractor,
I had to go back and do the test again to be sure, but the front tire spins freely while the other is on the ground - then the jack fell and Blue said to leave him alone :tractor:

So, I will need to find the front differential, u joint or drive assembly that has failed - where's the easiest place to begin

Thanks again for all your help
Danielle

Ilikeurtractor · Dec 25, 2014

What was the front drive shaft doing when you spun the tire? You'll need to remove the shaft guard to see what is going on if I remember correctly.

dlrepic · Dec 26, 2014

well, looks like the front end needs work. The drive shaft is turning but the front wheels are not. I'm hoping it's just a broken gear or something. Taking it apart to get to the carrier assembly (where I think the trouble is) will take me a while since I have no garage - already covered in mud (and other unmentionables) getting under there to take the shaft guard off.

If you disagree, please let me know where I should look first.
Thanks again & as a friend said - here's to having less tractor trouble in 2015

Ilikeurtractor · Dec 27, 2014

From my experiences the final drive assemblies (gear trains next to the wheels) tend to have more problems than the differential unit but you might as well have a look at all of it if you end up pulling the whole axle. There should be drain plugs on both final drive units IIRC. It's likely you'll see a lot of shavings in one of those and that may help indicate which one is giving you the problem. The 373D does not have u-joints in the front axle which makes for a much better axle design in my opinion (mainly since it can allow for tighter turns) so you won't have a broken u-joint in the axle itself.

grainger12002 · Dec 28, 2014

fairly easy to pull either of the side hsng (knuckles) off and see whats turning, then, if needed.. proceed to the ring and pinion, please keep us posted on your findings, for what its worth the ring is harder than the pinion shaft but you usually cant do one without the other

pswift408 · Dec 30, 2014

Twice I've had this problem with my Beaver. Both times, the bolts holding the ring gear to the differential have come loose one by one and fell into the bottom of the case. This leaves the ring gear in place turning, by itself unhooked to the diff. and not driving the axles. No damage to anything-just the old bolts-they turned into round metal balls from being rolled around between the ring gear and case, before the ring gear finally came unattached.Easy fix if this is the problem. Paul

dlrepic · Jan 9, 2015

Well, here's an update. I took the left front wheel off and drained the oil - let's just say I think I missed a section on where this oil is supplied/changed...apparently it's different than the transmission/hydraulic fluid that the rest of tractor uses. Is it part of the engine oil as I don't find anything except the drain & the check level plugs....anyway - the drain plug had a think layer of oil with shimmery silver specs - yes I know that indicates gears or something being ground. So I put the tractor in 4 wheel drive, the drive shaft turns, AND when I look inside the front assembly, the gears are turning in there as well. I put it in neutral and put the hub back on and in gear the wheel housing turned a bit and then stopped until I pulled it out a bit and then it turned again......so - do I continue and take the other wheel off to get to the drive assembly - OR do I put the tire back on and use it in 2 WD

Paul - where would I look for the bolts that have caused you issues?

Thanks
Danielle:turtle:

pswift408 · Jan 12, 2015

Danielle,
these bolts are in the differential part of your axle,which is in the center of the axle. There is a pinion gear [driveshaft turns it] and a ring gear [pinion turns it], which begins the process of turning the axle shafts. The bolts hold the ring gear in place. Sounds confusing-I"ll send a diagram. Do you have the repair manual?
Make sure BOTH L&R final drives "hubs" are ok before going further.
The axle uses 80w90 gear oil-the fill is a pipe plug[square head] on the top of the axle housing.
You"ll find the problem-you sound patient & cautious. gotta go, Paul