I have 4WD back!
I really think it was excessive force that broke it.
Broken zip-tie:
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Tried to take a couple more pictures, but the camera doesn't focus well close up.
May have cracked in the cold and sudden force. I really think that if I had warmed it up it wouldn't have broken.
Except for that break, the zip-ties seemed fine, not affected by the gear oil.
So like I said, I replaced both ties like last time but added two more short ones so that the actuator is held out more evenly all the way around.
Two new LONG zip-ties (just like before):
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I looped one around and zipped it up, and positioned it so the head of the ziptie was down at the bottom. Then I zipped the other one over the first one, and zipped it so the head was towards the top. I made sure the second tie didn't rub against any moving parts, where the first head is.
I then added two more shorter, regular-length zip-ties, and positioned the heads more-or-less 90deg away from the 1st two.
The ties in place:
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And underneath:
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TWO ties overlapped the head here so I used a 5th white baby zip-tie to keep them together.
Filling the differential:
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So that's basically it. Had it back into the car last night, drove it home with the hubs locked but in 2WD. Finally tried it out tonight. Working good!
James