4x4 went out when put on rear dif lock

   / 4x4 went out when put on rear dif lock #1  

mffarmall

Gold Member
Joined
Sep 16, 2005
Messages
396
Location
Colorado
Tractor
Farm Pro 2425, MF 50, JD B, Farmall Super MTA
I was stuck in the mud and it was late and cold. I was not thinking and already had her in 1 low 4x4 and then put on the rear dif lock and when I put it into gear heard a loud crack in the gear box. I felt it through the gear box. I can drive but I have no front power. I think it must be the gear box link snapped or came off. Any ideas, I'm not the only one to do this. But atlease I can still run in 2x4 and get work done. Power stearing, front end no leaking, 4x4 power switch will go in but no action. Put front end up and wheels will spin when turned by hand but with a clicking noise.
 
   / 4x4 went out when put on rear dif lock #2  
You broke something either in the driveshaft, the transfer case, or between the transfer case and the transmission. First remove the driveshaft housing, select 2wd, and spin the front tires again. If they in turn spin the driveshaft properly (no noise or vibration), move on to the transfer case. The transfer case itself is easy to drop for troubleshooting. While the gear oil is draining is a good time to disconnect the driveshaft at the transfer case end. Then unbolt the transfer case from the transmission case. It should drop right off. Once you have the transfer case in hand, you can turn the output shaft to see if it turns the middle gear (that's the big one at the top). If that's ok, the problem's in the gear train that drives the middle gear. You may have broken the claw. If so, you're going to have to split the tractor.

Either way, there are likely broken pieces to worry about. So - whether or not you end up splitting the tractor - try to get all the broken pieces out of the transfer case (easy) and/or the bottom of the transmission (not so easy). Even if you elect to put it back together and run the thing in 2wd for a while, you still don't want loose metal getting churned around in the gear oil.

//greg//
 
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   / 4x4 went out when put on rear dif lock #3  
Take the cover off the 4 x 4 driveshaft,see if the snap ring broke, and the drive ball bearings have came out.You should have 6- ball bearings in each coupler.Also once the cover is collapsed so you can see the shaft you can turn the front wheels to see if the 4x4 shaft is turning

Tommy
Affordable Tractor Sales
"Your Jinma Parts Superstore"
www.affordabletractorsalesco.co
 
   / 4x4 went out when put on rear dif lock #4  
Take the cover off the 4 x 4 driveshaft,see if the snap ring broke, and the drive ball bearings have came out.You should have 6- ball bearings in each coupler.Also once the cover is collapsed so you can see the shaft you can turn the front wheels to see if the 4x4 shaft is turning

Tommy
Affordable Tractor Sales
"Your Jinma Parts Superstore"
www.affordabletractorsalesco.co

If the snapring is OK, While the cover is off see if the front driveshaft is still hard coupled down to the front axle. IE: cannot rotate driveshaft. If you cannot, lift the front wheels off the ground and then try and rotate the driveshaft. You should be able to rotate the front wheels smoothly via the driveshaft(one will spin forward, one will spin backward). If that works, the problem lies in the main gearbox. My next point of inspection would be to lift the top creeper cover and inspect the 4X4 pawls/claws, and specifically their pins that join them to their respective shafts...
 
   / 4x4 went out when put on rear dif lock
  • Thread Starter
#5  
Thank you for the starting point. I will check on each item until I find what needs to be fixed. I will take pictures and put them on to this link. I have always learned more from fixing my tractor then anything else.
 
   / 4x4 went out when put on rear dif lock
  • Thread Starter
#6  
I did find one good thing. I had to get her home because I ran the battery down. So I pulled her backwards with the blade down like I was scraping the road. I was able to pull her and my front tires did not turn at all. The bucket was like a rudder and kept everything in line. I was even able to turn. I did this with my F150 in 2x4. I have 65s on the front and 75s on the back and didn't want to damage my gear box. I have enough work to do. I have a feeling that by taking everything apart it will help me when I need to do the clutch.
 
   / 4x4 went out when put on rear dif lock
  • Thread Starter
#7  
The problem will be near the front axle?
 
   / 4x4 went out when put on rear dif lock
  • Thread Starter
#8  
Take the cover off the 4 x 4 driveshaft,see if the snap ring broke, and the drive ball bearings have came out.You should have 6- ball bearings in each coupler.Also once the cover is collapsed so you can see the shaft you can turn the front wheels to see if the 4x4 shaft is turning

Tommy
Affordable Tractor Sales
"Your Jinma Parts Superstore"
www.affordabletractorsalesco.co

For the location: I will take it that this cover is that square that is infront of the 2/4 wd shifter or are you talking about the front drive crank case. When it broke I was in pousie and put it onto 4 and from under me I heard a pop. It was from under the seat or just front of me in the gearing.
 
   / 4x4 went out when put on rear dif lock #9  
Has this been broken over a year and not fixed?
 
   / 4x4 went out when put on rear dif lock #10  
The cover is on the front drive shaft itself. It is a rubber cover. Remove it and you will see the coupler underneath it that uses six balls in grooves in the drive shaft to connect it to the transfer case. Put down a tarp or something under the tractor before you remove that cover because if the snap ring has broken and the balls have come loose from the coupler, they'll fall on the ground when you take the cover off.
 
 
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