Are Skidder axles locked differentials?

[mjeselskis]

I'm working on beefing up the Vermeer trencher I picked up by adding a winch, tires, etc to make it more of a mini skidder. One limitation it has is that both axles are open differentials so when it gets stuck only two wheels spin. I'm thinking about locking up the rear differential but I don't know if locking the front will affect steering. The front is a steering axle and it does articulate in the middle also.

When I was thinking about this, I got wondering...Are skidder axles locked front and rear for true 4wd all the time?

Also, any way to lock the diff without welding the spiders solid? I'd like the option of removing it if need be. I've heard of people pouring molten lead into the spider gears? I've had a welded rear diff on a Jeep and it made a huge difference offroad.

Trencher pic here:
https://forestryforum.com/board/index.php/topic,48460.msg705771.html#msg705771

[mad murdock]

depends on the machine.  I think that most may be.  I have operated some that had a lock-in control on the floor, you would step on it to lock the front axle if you needed the extra traction, otherwise under normal conditions the front axle would not be in a locked condition.  the rear one was locked all the time.

[SPIKER]

not sure about the dif, you might be able to add a air locker to it with a small compressor addon through a switch.   
might have to find out WHO makes the dif, most of these smaller machines like this use a modified dif based off of something else.   just need to find out what the OTHER thing is and then aftermarket add on search...

mark

[Hanson]

My cousin just picked up a JD 540 and it has a solid rear and a locking front, I'll have to take some pictures of the operation and post them. I've only cut for firewood before now, but we've been out the last couple of weekends cutting pulp and will be till breakup 8) Its a new game for me.

[Maine372]

some are some arent. varies by brand and model. having the option for open diffs might be nice on a custom machine like that. so you can run on a driveway or lawn without tearing things up.

[shinnlinger]

WHile you could just weld it up and probably never regret it, I'm with Spiker.  Crawl under the machine and see if you can ID the make of the diffs and you might just then me able to find a locker for at least the front on and weld the rear.

Dave

[bill m]

You don't want the front locked all the time - it will not steer very well.

[barbender]

My pettibone skidder is locked up all the way around, an old Timberjack I used to run was the same way. I've read on the forum that JD440's snake through the woods really nice because you can unlock the differentials.  Mine tends to push, especially when you are backing up, the lighter back end doesn't get as much traction so you go what way the front axle wants to.

[Bobus2003]

The JD440 has a Pedal in the cab that is for Diff-lock. Mine hasn't worked as long as i've known the skidder and never been in a position where i needed it. Any 4x4 rig that has a Locked front end will be very hard to steer only wanting to go straight

[oldseabee]

Clark Ranger skidders had "No spins" in both axles. These would make all four wheels pull but in a turn, the outside wheel could over run the no spin and free wheel, but if the inside wheel was spinning the outside wheel would lock back in. The no spin was similar to what hot rodders called a "Detroit Locker".

[grassfed]

My JD 440B has the locked rear and lockable front with an on off foot switch. It works really well and about the only time that I need to lock the front is when I get hung up driving over a downed tree. Sometimes I forget to unlock it and it steers much worse (pushes) and tears up the ground a lot worse. I would not lock the front if I was you. 

[ephnyb]

My Timberjack 560 has a limited slip front axle and a lockable rear axle. this setup works very well.