[EricZ]

My ‘04 Tundra 4.7 TRD with 180k miles recently starting leaking front diff oil from the driver’s side half shaft seal not long after I replaced the passenger side axle. Not sure why the opposite side started leaking. Anyway, it dribbles about estimated half teaspoon over a couple days of sitting. The leaking side half shaft was replaced a year ago so it doesn’t have many miles. As long as the leak doesn’t get worse I’d like to leave it alone until that axle boot rips and/or that axle is shot. My plan is to top off the diff fluid at every oil change while the skid plate is off. Am I risking differential damage if the fluid level drops to the lower edge of the axle seal? Can I run thicker diff fluid in the hope to slow down the leak? I think stock calls for 75/90 synthetic in the front. I don’t run a lot of extended highway speeds if that matters much. If I’m risking diff damage I will change it sooner, just hoping to not be bothered right now. Have a lot going on. Thanks in advance.

 

[EricZ]

Anybody have any thoughts or experience with this?

 

[dyogim]

Should be fine as long as it doesn't run dry. Otherwise, you will cause bigger issues. Eventually, you want to fix it sooner than later. The risk is that, the leak may increase the longer you drive. I understand you have personal issues, we all do. Just don't forget about it.

As for the fix, you disconnect the sway bar end link and the remove the 4 bolts at the lower ball joint, that should give you enough "play" to remove the CV from the diff and replace the seal.

 

[cheapskate]

Isnt an 04 a sealed tranny? If thats the case and you cant check the fluid level how would you ever know if its low or not? If it were me I would change it now if I couldnt know the level. I would worry too much the tranny runs low on fluild and got cooked. It would suck knowing I toasted a $3k tranny over a $3 dollar seal.

 

[cheapskate]

Stupid double post.

 

[EricZ]

Thanks Dyogim. Yeah I’ve done the axles twice before. You’re right it’s not very difficult. Never did the seals though. Do they require any special tools like a puller to pull the old seal or to install the new one? Is there just one seal in the differential housing? Any thoughts on thicker diff fluid like maybe a 75-140 synthetic until I get around to it? No chance of me forgetting to do the job. I park it over cardboard in the garage to monitor the leak rate.