yesterday i had a good day up in the mountains playing on some trails, i got home last night and i could smell gear lube so investigated the smell, it looks like the seal around the yoke is leaking and throwing fluid all under my truck, need help on what to do, should i take into a shop or try to fix it myself

 

sounds like the pinion seal. i know on older trucks like mine, the diff was setup with a solid spacer so you can change it yourself. i believe on newer trucks/4runners it's set up with a crush sleeve so it's best to take it to somebody who knows what they're doing

 

If it's not leaking too bad, you can live with it for a while. Mine's been leaking for about a year and I still haven't had to add any fluid.

 

it leaking pretty bad, the whole underside by the rear end it covered in gear lube

 

Sounds like the pinion seal. Part costs about $7.00.
Even a non-wrencher can do this one. I did. Took me three seals before I got it on straight
Just make sure you count the threads when you take the bolt off, and then put it back the same number of threads.
Biggest trouble was ensuring the seal is set straight, before you set it flush. Otherwise, it's easy.

 

Just like Blair said, it is an easy fix. I did mine in under 2 hours. There is a large nut beneath the flange that is "indented" to prevent it from loosening up. The FSM say to replace this, which I did.