Another Front Diff fluid leak thread (pics)

[PProph]

Hi all, I've gone through a number of these already, I just want to cover my bases and get things done right.

I have a fluid leak that's causing a mess on my front diff and the oil pan. When I was underneath to diagnose my eventual U Joint replacement a couple months ago (thank you to everyone who helped then), I could clearly see that the driver's side seal out the front diff is leaking. There is an awful lot of mess and my first question is is it possible that the passenger side seal is also leaking? From what I understand this is way more difficult to change than the driver side. It's -25 out and I'm not looking forward to working on this. I'm also due for an oil change, and I am also of the understanding that there is in fact a passenger side front diff job that would require an oil pan drop, so I'd rather not put new oil in before that. Unfortunately I could not get to work on this before the snow flew and temps dropped. I'm trying to avoid use of 4wd also, but again, snow and ice the extra grip is required sometimes. I'm a little concerned that my fluid might be getting low and at the very least I'm going to get it up and level this weekend to check that out.

Anyways, my question is aside from the driver's side seal, what should I be checking out next? I haven't had any problems with the 4wd itself, though I thought I heard some unusual noise when I used it briefly this morning. I just need help diagnosing to make sure I solve what I can myself and worst case scenario get help on the rest. On the up my car guy is looking for work again so worst case I still should have to take it to a shop and have someone I trust to work on it.

Here are some snaps from what it looked like a couple months ago:








Help me diagnose properly and you may even receive a gold star or a cookie.

 

[The_Roadie]

Best way I know of to localize a leak or two is to pressure wash it all clean, and then monitor for fresh traces. If you replace the outer seal, you might be able to keep ahead of a small inner seal leak with more frequent top-offs.

 

[PProph]

Boy about the only thing I hate more than auto work in -25 is pressure washing underneath a vehicle in -25

Yeah I've got some superclean as well that I might use to clean it up I guess. The more I look at my own pictures the more I think the outer seal is my obvious problem that needs immediate attention. I just hope I didn't push this off too far, strapped for time on that ujoint job I didn't check my front diff levels when I had it level on blocks :blush: and I've been too busy to return my attention that way since. I'd hate to think my levels are low and causing any damage the few times I do require 4wd engaged.

I guess I'm gonna have to get the seal and tools required to try and get this done this weekend. Hopefully it's not too messy a job and I can do it in my parents' garage I'm headed to. I've never personally gone into a job like this, anything special I should know about taking off the parts I need to to get at that seal? I've noticed a lot of posts are very specific about things like getting the tripot out and whatnot which is great, but even more basic things like step by step from the moment I get the tire off would be helpful, I'd hate to make a stupid rookie mistake (or rather would love to make as few as possible).

Hey I finally got my heated seats done though! Thanks to the write up from the OS, and boy I'm glad I don't work in upholstery.

 

[PProph]

double poast.

after thinking this over I've decided to bring in help on this job. Winter is not the best time for me to tackle a new auto project, especially one that I do not yet have the proper tools to use. Thankfully I have a mechanic friend who has recently become more available for backyard work. He has the tools and knowhow to make it a quick job, and I'll be able to help and learn some of these processes for future reference.

Quick question, is the whole drop the oil pan to get at the inner seal thing a myth? When I first bought this TB I took it to a shop with the service 4wd light on, they told me about these seals and the oil pan drop thing. Frankly I probably should have replaced the outer seal then, but that's a moot point right now.

I just want to know if I should hold off on changing the oil, because I'd hate to do that and then have to do it again soon if that other seal is in fact giving me issues.

Either way I'll be doing this outer seal next week, I'll get it up and level tomorrow to check the diff fluid level and avoid using my 4wd til then. And hopefully it's warmer after I get the seal changed so I can wash up underneath without freezing my everything off.

 

[AtlWrk]

A. Getting to the inner seal does NOT require dropping the pan. You do have to remove the entire front differential. I think the confusion here is that in order to drop the pan you have to remove the diff, but not the other way around.

B. While not impossible, it is unlikely that you have a problem with your inner seal. It is not exposed to the elements like the outter seal is or take the abuse of a CV shaft. If you're really worried about it you can pull the splined disconnect on the passenger side. With a flashlight inspect the tube in the oil pan that the intermediate shaft runs through.

C. Be sure to inspect the pinion seal for leaks as well. I thought my outter seal was failing, only to find the fluid was originating farther back at the pinion seal and running forward. Like Roadie mentioned, clean it all off and reinspect to be sure.

 

[AtlWrk]

Service manual does say to remove the oil pan. Must be a clearance issue to physically remove it from the vehicle once it's all apart. Only someone who has actually done it could tell you for sure. Point remains that I'd bet your inner seal is just fine.

 

[HARDTRAILZ]

FWIW...I did not drop the pan when I swapped my front diff.