Prerunner rear diff noise help

Recently I went through a auto carwash that sprays the underside of the truck and while leaving the wash, there was a metal clicking that increased with speed coming from the mid/rear under the truck. The next day, it was gone. Now, a few weeks later, there seems to be alot of backlash in the gears as I can grab the drive shaft and rotate it probably 1/12 a turn back and forth. Doing so, I can hear the gears click/tap together. I hear the sound when going from drive to reverse while holding the brakes and when going from a stop. It's getting worse and this is my only vehicle so I can't have down time.
Any idea why it is doing that?
Could water have gotten in through the diff breather and damaged it?

Plz Help! I can upload a short video later tonight when I get off work. And I have the LSD.

 

Did you intend to say 1/12 of a rotation? That’s totally normal. If you meant 1/2 rotation, that’s a little excessive, I would be concerned that the pinion pre-load is out of spec. Not sure how that would be caused by a car wash though.
Water may have entered through the diff breather, I would recommend draining the diff and seeing if there is any water/metal shavings/small furry animals in there. Pretty easy to do and could give you a lot of information on the situation.

 

Are you sure it's not a u-joint?

 

Yeah, 1/12 turn.

The sound is coming from the diff for sure. I replaced one u joint a few years back and they are all still good. It honestly sounds like there is alot of space between the gears. I will be tarring it apart on Sat so I will post back what I find and load a vid tomorrow. Thx

 

Well, I have some time today so I'll be tackling the diff and post back what I find.

 

What did you find,,,,, inquiring minds want to know