Post by Neil on May 8, 2012 2:05:05 GMT 2
I had a bit of time to pull the old 2 way lsd apart today and examine the causes of the failure. Poor maintainance by Me was the likely culprit 
But it never does any harm to dig a bit further!
I was quite surprised to see nothing was ripped to shreads but the next series of photo's will hopefully show you whats lurking inside that diff case.
So call this a "How to dismantle your 7.5"lsd diff guide"
Nice clean bench to start with. Drained diff oil and loosened diff
back plate.
Now you can see the sprung plates in the Diff body.
A bit more closely...
Time to loosen the rear bearing carriers with a 14mm socket.
And now is a good time to punch match marks on the casing
before it all comes apart.
I did the same to line the casing with the crown wheel too.
To pop out the half shafts i just used a short pry bar between the back of the 14mm drive stud and casing.
The shafts are held in with sprung C clips so don't need a crank puller.
Once they pop out.
You can remove the bearing cradles and bolts. If you eat as much Chinese Takeaway as i do, the plastic food containers are awesome for keeping the Left /Right side separate.
LABEL EVERYTHING!!! THIS IS VERY IMPORTANT!!!
Your now ready to pull the diff from the casing. Needs to be wiggled a bit but comes out ok.
Clean up around the bench and put everything else to one side.
...Not like this Shit Nest i got going on!
Spiral grooves inside the inner race of the bearing are a nice touch. If you have a 3 leg bearing puller to hand at this point, use it. doubt your gunna be stupid enough to re use the old ones?!
Photo of the inside of the casing with pinion wheel at the back.
Now, Vice time
Take the C clip off the half shaft and use it to stand the diff up in the vice. Break the tension of all 8 14mm bolts with a windy gun.
In the above shots i have rotated the Diff Casing against the resistance of the shaft clockwise. You can see the big top plate
above the springs hit the right side of the slotted casing.
Now, when i rotate it counter clockwise it hits the left side of the slotted casing. This is not good, there should be more resistance.
Once the Top cover bolts have been freed off put the diff back on the bench.
The top cover is under tension from the springs so all bolts need backing off.
Once undone you can remove the top cover.
This is the bit you need to label up and NOT Mismatch
Three clutch pressure plates, one of which was worn to shit!
Also notice there is an unused spline on the gear shaft.
These diffs had no clutch discs from the factory, The only thing locking the diff is the friction between the plates and the back face of the gear!!!
ie Toyota pussied out on giving this car a proper locking diff in the final design stages.
But the weir kit will make use of those splines ;D
Put those to one side for now.
Now to remove the Internals.
With brass thrust washers on top.
why my diff failed?!
Snapped spring would account for the noise and shit lock up!
Bottom gear with Brass thrust washer left on top. See the grooves for Lubrication.
Three bottom clutch friction plates left.
I need to stack these up and replicate the thickness to my new weir kit so need to keep these safe.
So, that's how you take one apart. Now time to order a solid crush sleeve from weir to make sure nothing is a weak link to fail again..
As you can see the Weir maxgrip kits i already have contains 2 new Splined clutch discs and 4 new friction plates instead of the weak standard 6 friction plates, So will essentially make these Diff's lock up properly as they are pretty naff once the friction plates have worn.
But it never does any harm to dig a bit further!I was quite surprised to see nothing was ripped to shreads but the next series of photo's will hopefully show you whats lurking inside that diff case.
So call this a "How to dismantle your 7.5"lsd diff guide"
Nice clean bench to start with. Drained diff oil and loosened diff
back plate.
Now you can see the sprung plates in the Diff body.
A bit more closely...
Time to loosen the rear bearing carriers with a 14mm socket.
And now is a good time to punch match marks on the casing
before it all comes apart.
I did the same to line the casing with the crown wheel too.
To pop out the half shafts i just used a short pry bar between the back of the 14mm drive stud and casing.
The shafts are held in with sprung C clips so don't need a crank puller.
Once they pop out.
You can remove the bearing cradles and bolts. If you eat as much Chinese Takeaway as i do, the plastic food containers are awesome for keeping the Left /Right side separate.
LABEL EVERYTHING!!! THIS IS VERY IMPORTANT!!!
Your now ready to pull the diff from the casing. Needs to be wiggled a bit but comes out ok.
Clean up around the bench and put everything else to one side.
...Not like this Shit Nest i got going on!
Spiral grooves inside the inner race of the bearing are a nice touch. If you have a 3 leg bearing puller to hand at this point, use it. doubt your gunna be stupid enough to re use the old ones?!
Photo of the inside of the casing with pinion wheel at the back.
Now, Vice time
Take the C clip off the half shaft and use it to stand the diff up in the vice. Break the tension of all 8 14mm bolts with a windy gun.
In the above shots i have rotated the Diff Casing against the resistance of the shaft clockwise. You can see the big top plate
above the springs hit the right side of the slotted casing.
Now, when i rotate it counter clockwise it hits the left side of the slotted casing. This is not good, there should be more resistance.
Once the Top cover bolts have been freed off put the diff back on the bench.
The top cover is under tension from the springs so all bolts need backing off.
Once undone you can remove the top cover.
This is the bit you need to label up and NOT Mismatch
Three clutch pressure plates, one of which was worn to shit!
Also notice there is an unused spline on the gear shaft.
These diffs had no clutch discs from the factory, The only thing locking the diff is the friction between the plates and the back face of the gear!!!
ie Toyota pussied out on giving this car a proper locking diff in the final design stages.But the weir kit will make use of those splines ;D
Put those to one side for now.
Now to remove the Internals.
With brass thrust washers on top.
why my diff failed?!
Snapped spring would account for the noise and shit lock up!
Bottom gear with Brass thrust washer left on top. See the grooves for Lubrication.
Three bottom clutch friction plates left.
I need to stack these up and replicate the thickness to my new weir kit so need to keep these safe.
So, that's how you take one apart. Now time to order a solid crush sleeve from weir to make sure nothing is a weak link to fail again..
As you can see the Weir maxgrip kits i already have contains 2 new Splined clutch discs and 4 new friction plates instead of the weak standard 6 friction plates, So will essentially make these Diff's lock up properly as they are pretty naff once the friction plates have worn.
