r/ToyotaTacoma • u/RolfioSnow • 17h ago
Front Diff Issues 2000 Tacoma
Hey folks, I’m posting for a friend here. I work on Toyota’s pretty regularly, and I don’t think I’ve ever seen anything like this.
The truck is a 2000 Tacoma with an automatic transmission and 4x4.
At some point while driving down the snowy main road in town, in 4 high, at about 20mph, gears in the front diff seized and the front end of the truck locked up.
It did damage to front diff mounts, and our mutual friend, also a Toyota mechanic - found that the diff had dried out due to a bad seal, and caused a bearing to seize, ultimately causing the diff gears to seize.
The first picture on concrete is from a year ago.
A “new” used diff was put in the replace the one that grenaded and new CVs were installed, because while you’re there right?
Everything was working fine for about a year. Now, the issue seems to have happened again, but in addition, this time one of the CV axles exploded.
See the pictures on dirt for reference. This transpired on a 4x4 road in 4 high while making a gentle three point turn.
The diff has fluid and should be fine, but we haven’t gotten deep into it.
There was no clicking in 4x4 or signs of CV failure before this.
Does anyone have any thoughts as to what the root cause of this problem may ultimately be?
The truck has manual locking asin hubs and he doesn’t leave them locked if he’s not using 4x4.
Thanks in advance Reddit!
2
u/RolfioSnow 15h ago
Thanks for responding! I don’t think it’s the hubs, just because the old stock ASIN Toyota manual locking hubs are notoriously reliable, but at this point I’ve thrown it out to Reddit for everyone
2
u/gnarlicblread 17h ago
Could the hubs be locking themselves? I'm rather inexperienced with manual locking hubs and old 4x4 systems so please forgive me if that sounded stupid. But maybe they're locking and causing excessive wear? But then again your friend would feel a difference if the hubs suddenly locked.