What is happening here?

Yesterday, when I was installing my catalytic converter protection plate, I noticed oil slung into the transmission tunnel.

It appears the front part of my driveshaft? Is leaking and slinging oil when rotating, what is the cause of this and how do I fix it?

 

That looks like the transmission tail shaft seal is leaking. Here's a vid of someone replacing one on a Tacoma, its basically the same. Good luck.

https://www.youtube.com/watch?v=aC8yfiTiw3M

 

Good catch, by the sound of the music, it doesn't look that hard but I am sure that he edited out all the cuss words.

 

Dropping the shafts are 99% of the job.

 

Appreciate the reply and video. May wait until spring when it warms up again.

 

That doesn't look too bad honestly. Leave it alone, but keep an eye on it. If it begins to drip then worry about it.

 

Just an update - it has become worse. Towing my travel trailer to/from Colorado - everytime I stopped I could smell only what I could describe as "hot". The trans fluid slinging onto the exhausts made a terrible smell. I worry I might be losing more than before. We made it back no problems, trans temp stayed in the normal spot - but I am tackling this soon. I'll report back how it goes.

This is a good time to do my trans fluid change too.

https://www.tundratalk.net/threads/5-7-tundra-diy-transmission-fluid-change.106946/#post-769802

 

Yes... tend to it now, plz.

 

It also depends what your driveshaft maintenance interval is. My 2010 has grease fittings at the u-joints. It slings grease for a while after maintenance.

IMO, unless you see oil dripping off the housing, and it's the oil from the x-fer case, I'd leave it alone.

The reason being the seals are pretty good. If the seal got knocked out, it's likely the tail shaft bushing needs replaced which isn't hard but requires some basic tools most don't have.

 

check to see if you fall under that TSB for the driveline. My driveline was replaced along with that tail section in 08/09 when it started leaking.

 

Since I am 2WD, most likely. However it wouldn't be covered as its not a recall. I'll change the seal out, clean everything up and see if the splatter stops. Otherwise I will replace the driveshaft.

 

As I wrote above, check the freeplay of the yoke in the bushing. If there is up/down free play, it likely needs the brass bushing in the tailshaft replaced as well as the seal.

And well, why would the bushing go bad? Are the u-joints binding, or maybe the center support (if equipped). With the shaft out, test the joints.

 

Is it not possible the seal just cracked/dried out? This truck sat outside in hot Texas sun its whole life. All the rubber on the windows was disintegrating when I bought it.

Not discounting what you are saying, I will definitely do what you recommend. It’s just odd for it to start randomly.

 

Well I replaced it this past Saturday. Old seal came out with the $7.99 harbor freight seal puller, but it was a little difficult putting the new one back in. Used a PVC section to tap it back in. I've been driving everywhere in the truck (despite gas being $$$) and randomly crawling underneath it - so far no slinging ATF.

I also went ahead and did my trans flush with 4 gal of Valvoline Maxlife ATF. So now I am ready to go pick up my new travel trailer on Saturday (~1300 mile trip)