I've been working on my diffs, I figured I'd make a few notes on the difference.
I've got both diffs out of my 1999 100 series for gearing. Last winter I shredded the ring gear up front and decided to change both of them to 4.88s in the process.
The Toyota locker:
Is super simple - It simply adds a splined hub that is shifted along one axle shaft by an electrically operated shifter fork. (Which also has a vacuum line for some reason)
Here's a shot of my locker on the bench with the ring gear removed. The big teeth on the end match the hub to create the locking mechanism.
Pros: you can access all the major wear items on the outside of the axle housing.
The drive motor on the 100 has a drilled shaft, so no adjustment is needed.
The shaft moves left to right to lock the diff, and right to left to unlock. I *think* the vacuum line is there to prevent the shaft cavity from sucking up gear oil and allow a decent seal.
Beyond this motor assembly, there's just the shift fork that bolts to the shaft, and the hub section that slides along the axle and keys into the diff body.
This thing is DAMN simple. I suppose it could be improved by the addition of a manual engagement/disengagement method.
Con: could fail in locked or unlocked position.
Useful service note - if you're pulling the diff, lock it first to get the fork and hub out of the way, otherwise they'll catch on the way out of the diff housing.
ARB Locker:
We all know about them, they've been around forever.
The ARB locker works on the same basic premise - a splined hub engages between one axle shaft and the pinion assembly to stop the pinons from spinning.
In ARBs case, the created a hollow air piston that engages the hub. When air pressure is added, this creates and air spring that shifts the hub into place.
When air pressure is removed, a spring washer pushes the air piston back out of the assembly and the diff becomes open once again.
My air locker torn down on the bench. The wavy washer is the spring washer, the flat star hub next to it meshes with the right on the right side to lock. New piston seal is in the bag.
You can see damage to the side of the locker where broken ring teeth got chewed up.
Pro: This can be added to just about any diff.
Pro: (depending on persepectve) Failure mode will be in unlocked position.
Con: Requires external compressor and eventually needs to be rebuilt once in a while. Rebuild normally means replacing a couple of o-rings, but sometimes requires removal of the ring gear and dissasembly of the locker itself. (This is what I did, due to my shredded ring gear)
Con: While a simple concept, these are a bit more complicated.
Pro: Decent/responsive tech support and parts availability.
In my case, ARB reccomended inspection of the thrust washers, replacement of the piston seal and the o-rings. I decided to replace my thrust washers after inspection.
Anyhow, today's project is re-install of my rear locker diff and then maybe I'll get back to work on the front diff rebuild if I can still move after that.
I've got both diffs out of my 1999 100 series for gearing. Last winter I shredded the ring gear up front and decided to change both of them to 4.88s in the process.
The Toyota locker:
Is super simple - It simply adds a splined hub that is shifted along one axle shaft by an electrically operated shifter fork. (Which also has a vacuum line for some reason)
Here's a shot of my locker on the bench with the ring gear removed. The big teeth on the end match the hub to create the locking mechanism.
Pros: you can access all the major wear items on the outside of the axle housing.
The drive motor on the 100 has a drilled shaft, so no adjustment is needed.
The shaft moves left to right to lock the diff, and right to left to unlock. I *think* the vacuum line is there to prevent the shaft cavity from sucking up gear oil and allow a decent seal.
Beyond this motor assembly, there's just the shift fork that bolts to the shaft, and the hub section that slides along the axle and keys into the diff body.
This thing is DAMN simple. I suppose it could be improved by the addition of a manual engagement/disengagement method.
Con: could fail in locked or unlocked position.
Useful service note - if you're pulling the diff, lock it first to get the fork and hub out of the way, otherwise they'll catch on the way out of the diff housing.
ARB Locker:
We all know about them, they've been around forever.
The ARB locker works on the same basic premise - a splined hub engages between one axle shaft and the pinion assembly to stop the pinons from spinning.
In ARBs case, the created a hollow air piston that engages the hub. When air pressure is added, this creates and air spring that shifts the hub into place.
When air pressure is removed, a spring washer pushes the air piston back out of the assembly and the diff becomes open once again.
My air locker torn down on the bench. The wavy washer is the spring washer, the flat star hub next to it meshes with the right on the right side to lock. New piston seal is in the bag.
You can see damage to the side of the locker where broken ring teeth got chewed up.
Pro: This can be added to just about any diff.
Pro: (depending on persepectve) Failure mode will be in unlocked position.
Con: Requires external compressor and eventually needs to be rebuilt once in a while. Rebuild normally means replacing a couple of o-rings, but sometimes requires removal of the ring gear and dissasembly of the locker itself. (This is what I did, due to my shredded ring gear)
Con: While a simple concept, these are a bit more complicated.
Pro: Decent/responsive tech support and parts availability.
In my case, ARB reccomended inspection of the thrust washers, replacement of the piston seal and the o-rings. I decided to replace my thrust washers after inspection.
Anyhow, today's project is re-install of my rear locker diff and then maybe I'll get back to work on the front diff rebuild if I can still move after that.
