Lockrite diff failure

[OVOXO]

Hey guys, Got a Lockrite locker from T-Boon on here, that was in his surf for ages with no problems.

I then put the diff head in my Landcruiser and used it for a number of months. All of a sudden, i drove home and it decided to make a major clunking. Dropped the oil and few shards came out.

Pulled the diff out, there was no teeth missing on the crown wheel (which is what I thought had happened) but the lockrite pin was all damaged. Spun it round by hand, and its making contact with the pinion.


Anyone have any light on how or why this would have happened? And also, how I could prevent it from happening again? Fixable?

[suzolla]

Bit of a bugger,
The cross pin should be held in place by a small pin that goes through the carrier and the end of the cross pin, I would remove crown wheel, take pin out, clean up end, check that the locating pin holes are clear, refit and fit new locating pin.
Probably want to dress any damage on the end of pinion to prevent damage to ring gear.
Cheers
Tim

[madlux]

Yep, the center pin in mine cracked in two so the end that wasn't held by the retaining pin, droped down and everynow and then would hit the pinion and make a loud clunking.

[suzolla]

Yes, good point about the cross pin being possibly broken.

[tweake]

just watch what cross pin you use. factory ones are a lot stronger than a lot of the aftermarket ones.

also i would check the locker clearance cause that looks to be way to loose.

[MNC]

Where in NZ are you?

That pin should sit flush with the carrier. Looks like you need a replacement pin, retaining bolt, and pinion.

What size (inch) and ratio landcruiser diff is it?

[OVOXO]

I'm fairly sure it's a 9 1/4" diff, and I know it's 3.9 ratio.

However, I need a 4.3 ratio, so may be looking at getting a whole new setup, as this is the second diff i've blown in less than a year.

[T-Boon]

You just daily drive too hard !

[tweake]

by the looks of that photo the locker clearance is way to much. i guess your missing the shims. i was trying to find a pic to confirm the clearance.
with the locker unlocked like that in the pic, the two halves of the locker should be almost touching each other, not have that big gap between them.

with so much clearance it will have a big gap between pin and the locker driver, so the pin gets slammed into the locker which is probably what broke the pin.

[Petemcc]

I'm fairly sure it's a 9 1/4" diff, and I know it's 3.9 ratio.

However, I need a 4.3 ratio, so may be looking at getting a whole new setup, as this is the second diff i've blown in less than a year.

\

So you put a locker from a 8inch surf diff in a cruiser diff? That might explain the clearance issues. I am pretty sure the lockers are different.

[T-Boon]

I'm fairly sure it's a 9 1/4" diff, and I know it's 3.9 ratio.

However, I need a 4.3 ratio, so may be looking at getting a whole new setup, as this is the second diff i've blown in less than a year.

\

So you put a locker from a 8inch surf diff in a cruiser diff? That might explain the clearance issues. I am pretty sure the lockers are different.

No it was the entire head, crown wheel and pinion assembly.

[tweake]

for an 8" this is what a lockrite should look like.




many thanks to Zuk.