My rear diff is leaking from the driveshaft side, it has been slowly getting worst. Which leads me to believe the diff seal is shot. My question is what would make the seal go? Is there a breather tube that might be plugged somewhere? Thanks

 

age/mileage plays a factor

 

I just had my rear diff. seal replaced as well as the pinoin seal on my truck. I have about 70,000 miles on mine. It was like $130.

 

Wirelessly posted (Timberwolf)

My rig has 68,000kms (41,000miles) though. Shitty luck I\'m guessing.

 

45,000 miles on my 07 F150. Already had to do an axle seal and ball joints. Doesn't really matter what make vehicle you buy anymore. The big 3 cant seem to make a reliable truck anymore. So chances are the seals just bad from being poor quality like my axle seal was. I Might get a toyota for my next truck. O_o

 

did you get it done? Ive had mine replaced twice now and im around 78,000 miles. I got it replaced a year ago but a shop who just threw a new seal in it and I literally this past weekend just spent all weekend doing it the proper way and taking everything out of the rear diff and putting a new crush sleeve in. I hope I dont have anymore issues after this, but anything from your vent tube being blocked, to dirt n dust getting around and in the seal, pinion flange starts to get a groove in it, offroading, etc etc trust me ive not been happy about the seal issue either.

 

I eventually did, and it solved the issue. New gear oil and a new u-joint, runs like a top now. The guy I bring it to is a good friend, so at the very least I know he is gonna do a great job. Plus a case a beer seals the deal. Rotten luck on the shop that did your seal man.

 

ah I guess they didnt do to bad of a job, the seal lasted a year and like I said just getting mud/dirt, and offroading or going across fields causing the rear to bounce up and down fast can cause it so who knows if it was them or me, obviously it lasted a year lol.

I assume you all just threw a new seal in it, didnt go all out and do the proper way?

 

"I assume you all just threw a new seal in it, didnt go all out and do the proper way?"

How do you mean?

 

MOST, myself included usually just upbolt the driveshaft, mark the nut, take it off and pop the flange off and put a new seal in and put it all back together while making sure that the nut goes back exactly where it was or maybe 1/16th of a turn past it to keep the proper pinion bearing preload from the crush sleeve. Almost every shop will do it this way and as well as most people do it this way. The problem is the crush sleeve is just that a metal ring, and once crushed it will not loosen up. In theory if you just put the nut back where it was it will keep the same preload it had and everything will work out but that doesnt work everytime.

Proper way is to take of wheels, take of drums, drain rear diff, remove carrier pin bolt and carrier pin, push axles in and remove c clips, then slide axles out, then take off bearing caps, and pull the entire carrier and shims out. Then go around and take driveshaft off if you didnt already and use an inch pound torque wrench to measure the rotational torque to see how much preload is on the pinion bearings. Then you take the nut off, take flange off, take of seal, and bearing, then spin around and pull the pinion gear out. At this point the rear is completly empty and you will then slide the old crush sleeve off the pinion. Then you put a new crush sleeve back in its place, put pinion gear back in and install bearings back on it. New seal, flange back on, and put the nut back on (or some use a new nut.) You then have to torque the nut back down until you start crushing the new crush sleeve, once there you slowly tighten the nut little by little, stopping and checking the new preload until your within specs, then reverse it all back together like normal.

That was obviously the quick run through version but you can see why almost no one does it the "proper" way as well as why hardly any shops will do it for a good price, its just so much work to do for a cheap seal and crush sleeve both of which are cheap as hell. Its just the nature of a crush sleeve application.

The first time I had a shop do it and they just did it the cheap way of popping a new seal in and putting the nut back where it was at, and going by "feel" or the drag of the pinion flange. It lasted a year before the seal went out again and my bearings looked fine, so obviously it worked out for me just like it has for lots of people. BUT there have been people that the spec didn't stay within the limits and it ruined the rear and had to have a new rear, or a rebuild done. I got away with it once, I def wasn't going to try and chance it a 2nd time especially with still the same crush sleeve. I literally just did this, this past weekend and I hope I dont have to do it again for a LONG time, and so far so good, so I guess I did a good job. All the shops around here would only do it that way if it was marked as a rebuild price which really doesnt make sense to me, providing that you put everything back the exact way it came out, all the tolerances and settings should still stay where they were at, which IMO is the hardest part of the actual rebuild process. SO I dont see how with that out of the equation why they can do it, but most shops told me straight up that if they did if for a cheap price, they couldnt afford to pay their guys that many hours to do it and still make money off of it. He basically went out to say that its just ALOT of work for alittle seal which is why they dont do it, that if I just want the standard way done to give him a call and goodluck. I appreciate his honesty and the truth but that didn't help my situation lol. I actually only know one person that has a shop that will do it the proper way for a cheap good price and he's nowhere near me so I did it myself. I figure for the rebuild price id have to pay, I could do it myself and worse comes to worse if it messes up, well im out the same price as I woulda been originally and ill just regear now.

SO that explains the "Proper" way to replace it but like I said, now you see why hardly anyone does it that way. Its just up to the individual person if they want to take the risk. Hope that sheds some light.

 

^ you got writers block?


hahaha jk

 

actually i did in a few parts lol, it was so much that I had to stop and recollect my thoughts. I havent reread everything I typed so im sure its all choppy and hard as **** to read but it basically is the step by step process of taking half the damn truck apart and emptying out the rear diff and building it all back, so it kinda has to be long lol. Its like someone telling you how to build a most of a motor, you just CANT explain anything in any sort of detail without just spewing into tons and tons of info.

BUT he asked the proper way so that helps give him an idea.

 

Dave, how much of a difference did you notice after the seal and fluid change?

 

@Taylor, Well, the bottom of my diff is dry now. Compared to a slime coated slow leak diff it was before. I was never really worried about it till I decided to re paint my rear end and noticed how caked on this gunk was. More of a appearance eye sore resolved, and no real change in "feel" from before. Correct me if I'm wrong but I would bet that a prolonged leaky seal not repaired could lead to some diff damage. i.e. low fluid/over heat.

@ZWilson07 I'm trying to wrap my head around all that work you have done to fix this problem, holy smokes man! So far so good on the seal here.

 

@ZWilson07 I'm trying to wrap my head around all that work you have done to fix this problem, holy smokes man! So far so good on the seal here.[/QUOTE]

well its not that ive done alot of extra work to fix a problem, its just the proper way to do it when dealing with a crush sleeve application. I just had to explain out every step, but the actual general idea is pretty simple. Also like I said I as well as many others have had it done before with just the normal throw a new seal in it and put the nut back where it was at and got by, BUT I could have ended up needing a new rebuild and there have been people, even on this site that has had to do that. So for when the seal went out again like a year and a half later, I didn't want to risk it for a 2nd time.

In general, you have to replace the seal and in doing so you have to take off the nut off that holds the pinion flange on to get to the sela behind it. That nut crushes the metal crush sleeve, which in turn preloads the bearings on your pinion gear. Even if you put the nut back exactly where it was at with the old crush sleeve, alot of times the preload still isn't within the proper range that it needs to be which in turn could cause your bearings to go bad which will lead to you having to rebuild the differential.

So theres only one way to properly do it all and thats to put a new crush sleeve in and redo the preload on the bearings but you cant access it through the end of the rear diff that your seal sits. So the only way to get to it is to take the pinion gear out and slide it off, which obviously where that is located at requires you to completely empty the rear differential and put it back together. Thats just the design that it has, and it is what it is I guess. Hope that helps give a quicker understanding without having to wrap your head around the step by step.

 

Don't feel bad about it going out in a year, I did a front axle half shaft seal and it made it a whopping two months, and yes, I did it right and yes, it was lubed and not put back together dry. Then, just to get in my face, the front pinion started leaking a few months after that. I'll be doing the crush sleeve, new nut, torque wrench for correct preload boogie real soon here, and no, I wouldn't dream of doing it the quick and easy way. Really, the parts cost is pretty cheap. Glad I always do my own work, someones gonna get paid for the labor on this job, and with shop rates as they are, I really like the tax free income in my pocket.

Gut instinct tells me that the vendor(s) for this seal have a little material quality issue. What I can't remember is if the National seal that I installed was made in a country I avoid buying from (ie, china).

I see people talk about checking the front axle vent tube for plugging. I did that to mine yesterday and predictably, no problems found. I really have to wonder if anyone has somehow plugged that vent given its location and design.

 

Hey sorry about not getting back to you last weekend, apparently all the pics I took when I did mine were on my now dead desktop......did you take any pics for a write up? Glad it went well, it's really not tough, just need the dial type torque wrench and be sure to mark the carrier bearing caps so they go back on the same way. A good write might help people in the future.

 

Feel like doing up a "how to" when you get the time? I honestly did not know about this correct method.

 

I honestly was going to but once I got into it, its just so hard to stop and and take pictures. When dealing with the driveshaft and rearend stuff your hands just get sooooo filthy with dirty and gear oil. Even when I wore gloves, id still have to take them off and on and even when dealing with vinyl gloves they like to stick to your hands and are a pain to take off and on. So I just ended up saying F it and didnt take abunch because I needed to get it done, but I might end up doing something with it here when I have more time to let it sit or with my luck itll start leaking again. Like buckgnary stated its really not THAT hard to do and wrap your head around especially once you get in there and you know how everything works and what does what, its just really time consuming and if you dont take proper steps on certain things, it could end your day in a hurry.

If anyone needs help with it they can ask me w.e they need and ill walk them through it. I didnt have a how-to to go by, but I had Toreadors4x4 as well as some others help at all times through text and I got some nice vids I found that helped alot that I saved if anyone needs them. So just let me know what you all need.

 

Not difficult at all to do. If you have access to the necessary tools then go for it.

 

Blah blah blah blah blah. All I understood from that is that you are a cheap bastard that doesn't want to pay for the work that needs to be done. If they have to put 6 hours of work into it, then you need to pay them for 6 hours of work. Who cares if the seal is $18, you need to pay them for all that work. If you want it done your way for cheap, go ahead and do it yourself.

With that said, I had my front pinion seal replaced a couple years ago, they did it the "cheap way" (aka the way I would have done it, if I felt like fukcing with it). Its been to the dunes 3 times and withstood 4 winters with no problems what so ever.

 

I don't even have a garage. I park out in a lot within my complex. So my work is done out there. I fix what I can within my limitations and space(minor engine/all fluids/brakes/suspension, but overhaul work like that I won't attempt in my parking space. Kudos to your knowledge @Zwilson07, but I am way to busy at this time till the new year to attempt something like this (proper way). I believe there will be a time when I am willing to learn this method when I have more free time...from this forum of course and some tech buddies of mine who would be willing to have a few and jump right into this without a doubt. Still blows my mind for all that work for a $20 part.