overflowing diff fluid

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Mar 27, 2003
north of 49
Hi folks, I am getting plain tired of the problems I have been having since I got the axles redone about 2 months ago. I am either a serious mechanical hypochondriac or I can’t catch a break.

On the weekend I checked the front diff level for the first time since the work was done. About half a litre poured out before I plugged it up again and it was still flowing. It also did not look thick enough to be SAE90 gear oil which I use in my outboard leg all the time. Looks like 90 weight but pours like normal engine oil. &nbsp:Dark brown and opaque with no streaks. I called the mechanic who did the axle rebuild to ask. He doesn’t recall touching the diff oil. I pointed out that he had told me at the time that it was overfilled when it came in and had water in it too, and that he said he had taken care of that. He didn’t recall. I then asked him how he could have done the inner axle seals without touching the diff fluid. Oh I didn’t do the inner seals he says. I argue that he did but he stands firm that I didn’t because “he’d have to pull the gears to do that”. I know I specifically asked him to do them because I was working off advice given on the 80scool board as to what to do. He told me at the time he would. Now he says I absolutely did not ask him to it and he would have said no if I’d asked. The bill just says “replace seals”. The way the discussion ended, I can either sue this guy or move on.

So I assume the inner seals are leaking as I don’t know how you could overfill it that much. I am thinking with so much fluid coming out lots of grease must have migrated so I should just go to another mechanic and get it redone completely. This would also possibly address the stiff steering problem I’ve had since the job was done. Any other suggestions are welcomed.
Sorry to hear about this -- what a stress --

-- where did you get the work done -- a Toyota dealership? You can always bark upstream, if so --

-- also, did your bill reflect the amount normally charged by a dealer to do the seals, too?

-- I'm getting 180K service done on my Honda -- I always ask for the old parts (water pump/timing belt) when they're done --

-- I would go back to wherever it was done and raise hell -- the mechanic sounds like a jerk, and if you're in their face, it might serve you better --

-- eric :urinate:

I have been through this nightmare just recently, I had my 97 LX450 done at a dealership and they had to go in 3 times to correct the problem, as there are so many marginal errors that can be done if the mechanic is not familiar with LC Front Diff / Axle work.

With the help of C-Dan, Junk, Beowulf, Landtank as well as others on this board I was able to get the dealer to go in everytime and correct the inner seals install, as they failed every time they had them done.

If I am understanding you correctly, the mechanic is not admitting the fact that he had done the work, I would seek the advise of a reputable mechanic in the area to see if the job was really done, and from there you can just take the other mechanic findings and pursue the other in court.

(my openion based on what you said, I doubet that the job was performed period on your rig).

My question to you is: how many miles did you put on your rig after they completed the re-built of the front axle ????

Let us know

Not to be totally negative, but i feel you got hosed

This mechanic would of noticed "excess" diff fluid pouring out the axle seals when the birfield / axle was removed - period.

Now, if he only removed / replaced the disc brakes, then those wheel / brake seals would of been replaced, and he may not of seen any diff fluid.

Did he fill the knuckles with diff fluid, which could be the cause of the excess and / or "rough" steering feel as you describe.

I would be back there :urinate: all over the place, effectively detailing plans to file complaints with auto board, business association, etc. Even though you expect a professional serivce / job, if you didn't inspect / review the completed work before accepting / been some time, you are somewhat hosed again.

Sorry to hear you're still having problems.

I cannot remember if you did the axle breather mod. The instructions are part of the "diff breather extension" project. The reason for asking is that you are suggesting that the front diff fluid is overfilled and that the reason (I think) is that grease is flowing past the inner axle seal and into the diff. Christo posted a pic of a diff with this problem.  If your breathers are clogged (and sometimes if they are not) your diff will create a vacuum and suck grease past the seals.  Some people are pumping vast quantities of grease at the square plug at the back of the knuckle. Some people theorize that this grease will get pumped past the seal and into the diff.  Either of these could cause the symptoms you are seeing but the thing in common would be a definite discoloration of the diff fluid. The diff fluid will have a green milky look if there was grease contamination.

If you don't have this grease contamination then you have to guess that the diff was simply overfilled with gear oil. Not good, but not terribly bad either. Pull the fill plug and let it drain until level with the fill plug.

It sounds like you and your mechanic are having a "failure to communicate."   He thinks you are talking about a seal in the diff. You are talking about a seal just inside the end of the axle tubes (one on each side.)  

FWIW, you do not have to drain the front diff fluid to do the knuckles so maybe he didn't touch it as he said.  Joe is correct though, excess fluid would pour out the end of the axle tubes.

Thanks for letting me vent.

He says he did not replace the inner seals. I have no reason to disbelieve him. Maybe he did and thinks I'm talking about another set of seals.

There is not much to argue about here. I say I asked him to replace the inner seals and he says I did not. I could sue and it would be my word against his, plus I'd need a mechanic to come in and explain why logically he should have known to replace the inner seals (If I had such a mechanic he would have done the work for me)

At the time I asked that he use the moly grease specified in the owner's manual for the repack instead of his normal grease. He told me he did as I asked. I have added nothing to the knuckles since this job was done. There are no signs of contamination in the diff fluid but I also can't see how you could get an extra half litre plus in there. Green and goopy is how he said the diff fluid was when I brought it in. It is not that way now. I will drain off the rest tonight so I can figure how much extra I am carting around.

I have all the parts for the diff extension mod. I went to do it 3 weeks ago and found out the p clamp holes were too small. They are now drill pressed out and due for imminent installation. Maybe that will cut down on the problem.
Don't forget, Semlin, you can merely clean the breathers out and re-assemble them without putting the extensions on -- that'll likely rid you of your vacuum problem for now -- I found the whole extension-project too lengthy at the time I was doing it (it was getting dark!), so I just cleaned up the existing assemblies and modified the breathers, as Beo's instructions advised --

Semlin, I think you hit the nail on the head when you said suing would be your word against his. All you'd be doing is feeding a lawyer's dogs. (Even our dogs gotta' eat!)

This is why I almost always do the work myself. Unless I know the business personally, they don't touch my rig. (Handy representing the Toyota dealership... 8) )

If I were you, I'd redo the inner seals myself, check the breathers, and try to verify what new seals/bearings etc. were put in by the previous mechanic, just for my own peace of mind.

Um, WOW.......................

It is not un-heard of for the fluid to expand. Giving the guy the benefit of the doubt, in say for example a Dana 60 axle the inner seals are right at the diff and it requires MAJOR surgery to get to them. He may have that configuration in mind when he is saying he didn't do that. I would specifically ask him if he changed the little seals at the end of the axle tube at the knuckle. He may say " oh those ones, yes" or maybe "nope". It is possible to overfill the diff if the vehicle or the housing is on an odd angle. Before you do too much, see what he says after you narrow down the geography. He may have overfilled the diff and replaced the seals, or maybe he's worthless. Does the RO detail part numbers replaced?
I guess where I'm going is, find out as much as you can before you un-load on him. You will have much better ground to work from and will be much less likely to embarrass yourself.

My .02 Dan
I'm thinking along the same lines as Dan. There are very few wrenches out there who don't do the work they say they do. There just is not a lot of percentage in it. Fluid certainly expands and is easy to overfill if the front is higher than the rear and you are using a pump to fill it. It does not mean the axle seals are leaking. i would not call the axle seals you are referring to as inner axle seals. The cruiser does not have inner axle seals. It has one set of seals on the outer ends of the axles.
Your RO ought to have at least the parts numbers and costs for the parts that were installed.
For what it's worth, I changed my seals and repacked the Birf. 2 months later, like you, I checked the diff oil level and the same thing happened - oil pouring out.

Like you I have concluded that the 'extra' must be made up of grease. The opinion of the group at the time was that I should change the diff oil and wait and see. I've done that and so far the diff oil has stayed the same.

There are two possible conclusions: Either I overfilled the diff the first time (truck not level) or, the level has stayed the same because I've already washed all the grease out !
Either way, I've had enough of worrying about it.

Don't know what you can do about your mechanic.

Cheers, Jim
My question is: what would cause the heavy / stiff steering that semlin is experiencing ?

Would it be The Diff. oil migrating to the knuckles ?

Since the purpose of the differential is to allow the wheels to turn at different rates of speed I'd sooner think that grease is getting into the diff making it harder for it to do it's job and producing some windup. Haven't experienced it first hand but have seen a nasty pic from Christo showing a diff full of grease.
It does not sound like there is a significant amount of grease in the diff according to what Semlin said:

" Looks like 90 weight but pours like normal engine oil. &nbsp:Dark brown and opaque with no streaks. "

Jim your experience is reassuring (I think). How much would you say poured out of the check hole? Was it green and streaky indicating grease contamination or dark brown like mine? As you say, maybe the solution is to wait and see and think happy thoughts. Maybe someone overfilled my axle (or my knuckle) leading to this problem.

I checked the bill last night. Maybe we are talking at cross purposes. There is no parts breakdown but it refers separately to replacing the axles seals (plural) on each side. The overall price for parts triggered a memory that I talked to him specifically about the seals because his parts estimate was half the parts estimate of the other mechanic I got a quote on the job from. I seem to recall the explanation was the other guy was going to order a kit and was marking it up big time, while this guy ordered the parts separately (which was cheaper) and didn’t mark it up. Anyway I am now dead certain I confirmed with him he was ordering the outer and inner seals because of this discrepancy. I will bring the bill in to work tomorrow so I have the invoice number and call his office to find out what parts they ordered.

I was also billed $10 for gear oil so he must have replaced some.

C-Dan, I have gone out of my way not to get mad at this guy although it is hard as he lacks a bedside manner. If I have embarrassed myself by jumping to incorrect conclusions it’s because he won’t take the time to work with me to understand the problem. Although I have a steering problem since I took the truck in this is not connected to the work and not his problem. Although my diff fluid is overflowing since I took the truck in, it must be the guy before whom overfilled it and this is not his problem.

BTW, my stiff steering problem has been roughly the same since the work was done (it got a little better after I had the power steering flushed and cleaned). I therefore doubt it is due to diff fluid leaking into the knuckle, and I cannot believe he would have filled the knuckle with diff oil to begin with. Is there anyway to check that? What should my knuckles look like right now in terms of extruding grease or oil?

Anyway, I am going to change the diff oil this weekend and see what comes out.
My diff oil had grease in it. Hard to say how much but it looked contaminated rather than the nice clear honey colour oil I put in. I would say I had about a quarter of a pint spill out when I took the nut off the diff. If yours had grease in it I think you would notice the same as me. My guess is that yours was just overfilled.
Did the stiff steering happen after the seal replacement? I wonder if he took the whole knuckle off and did not pre-load the knuckle bearings correctly.
I did not find it neccesary to take the knuckles off to replace the axle seal, but that's the only seal I replaced the last time.
The 2 easiest mistakes to make on a rebuild are probably getting the inner seal in backwards and mistakenly thinking the knuckle should be "packed" with moly. Either one will give you problems but both together would probably be disasterous. Something like fresh playdoh through a funfactory I'd imagine.
Since your changing the diff oil this weekend maybe you can see something through the fill hole. If you jack up one wheel and have the transfer in Neutral you couold spin the diff internally and maybe judge better what might be going on if anything at all. I've never tried this, maybe someone else can comment either way on the idea.

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