How long should axle seal last ?

[Kalawang]

I changed both my front axle seals less than a year ago and now I see grease sneaking out again. I really don't want to have to do this every year and I'm tempted to ignore it for a while and just add grease until the problem worsens. So far only grease is coming out so I doubt I'm doing additional damage. However I'm not all that certain.

I used substitute seals when I changed them last. They looked the same and cost a third of the Toy originals. Would Toy originals last long enough to make the added cost worthwhile ?



Kalawang

 

[topend yobbo]

Should be a yearly or 40,000 klm job anyway.
Cruiser = BIG $'s.
Thats life.
Would you rather drive a 100 series corrola?

 

[cool dad]

saw your post at 4x4 ph a while ago. well I have the same problem and have not given much attention to it till you raised it. So is it just a short mechanical job without too much expense?

 

[Kalawang]

Cool Dad it's more like a Birf job and done professionally, about a 3-4 hour job per wheel. That included an oil seal change as I was already that deep so I changed them regardless they didn't need it. If I hadn't run out of cash I would have changed the wheel bearings too.


Kalawang

 

[RavenTai]

If it is only a small ammount of grease and no gear oil than that is normal.

be careful adding grease do not add to much or it will wind up in your gear oil.

the spec is 3/4 full, with is pretty hard to judge from the little hole looking at grease slung all over the place.

 

[elmariachi]

The next time you tear one down and have it all cleaned up for reassembly, slide the Toyota seal and then the aftermarket seal on the axle and up onto its smooth perch and compare. The only aftermarket seal I have ever found fit like crap. Doing this really helps you better understand how it fits and why you have to be gentle on it when sliding the axle back in place. If the Toyota seal were $25 and the aftermarket seal were free, I'd still pay the $25 to keep from having to go back in. At least with Toyota I feel reasonably certain its going to give me max life. But like RavenTai says, a lot of times its not the seal, its overfilling the knuckle cavity.

 

[photogod]

But like RavenTai says, a lot of times its not the seal, its overfilling the knuckle cavity.

Can you guys point me to the page in the FSM that tells you not to over fill the birf??? I can't seem to find it and the only thing I can find says to "Top off" the cavity. Where does it tell you 3/4 or is this just a judgment call? Inquiring minds need to know.

 

[SteveH]

Also, remove the Toyota vent cap on the diff vent, and extend the vent hose into the engine compartment with a cheap fuel filter on the end. Many seal failures are due to pressure in the diff. from the axle heat and the crummy Toyota vent cap design.

My last (genuine Toyota) axle tube seals went 55K miles and 4 years without leaking - may have gone a lot longer - who knows.

 

[Rookie2]

Should be a yearly or 40,000 klm job anyway.
Cruiser = BIG $'s.
Thats life.
Would you rather drive a 100 series corrola?

What...?? That seems a little over excessive. I would expect the axle seals to last as long as a typical birf job interval.. 75k to 100k.

Get the Oem seals. A $3 seal can't be to good.

 

[lx450landcruiser]

My last (genuine Toyota) axle tube seals went 55K miles and 4 years without leaking - may have gone a lot longer - who knows.[/QUOTE]

my truck had never had the seals replaced when i got it, 143K many have gone farther.

 

[RavenTai]

Can you guys point me to the page in the FSM that tells you not to over fill the birf??? I can't seem to find it and the only thing I can find says to "Top off" the cavity. Where does it tell you 3/4 or is this just a judgment call? Inquiring minds need to know.

RM482U
1996 LEXUS LX450
page SA-19
SUSPENSION AND AXLE –
STEERING KNUCKLE AND AXLE SHAFT INSTALLATION
step #11

11. PACK MOLYBDENUM DISULFIDE LITHIUM BASE
GREASE, NLGI NO.2
Pack molybdenum disulfide lithium base grease, NLGI No.2
into the knuckle to about 3 fourths of the knuckle.

same quote is all over the archives here also.

 

[Kalawang]

I'll follow Raventai's advice and just add a bit of grease periodically, sort of estimating whats coming out as I put in. Best I can see, it's just grease and no apparent mix of gear oil. If Gear oil were part of the mix I'd expect it to flow and not just ooze.

I'm truly reluctant to go in there again. The Toy parts cost me in the area of $200 as against the replacements' $50. Wheel Bearings and Oil seals would also add to the cost, but it just doesn't make sense to me to go that deep and not change everything I see if only as a bit of assurance that I won't be going in there again anytime soon.

Adding a bit of grease and cleaning off the old can't be all that bad I guess.


Kalawang

 

[photogod]

RM482U
1996 LEXUS LX450
page SA-19
SUSPENSION AND AXLE –
STEERING KNUCKLE AND AXLE SHAFT INSTALLATION
step #11

same quote is all over the archives here also.

I read that but that is when you are doing a rebuild not a mantainance lube. I doubt that you could pack the ball full at that point. Just a thought. Page MA-14 under Repack front wheel bearing states to "Remove the screw plug from each steering knuckle and repack with lubricant." I guess if you fill it with lube from your gun it would settle out to about 3/4 full??? My question was slanted towards the maintainance side rather than the rebuild side.

 

[Rookie2]

I read that but that is when you are doing a rebuild not a mantainance lube. I doubt that you could pack the ball full at that point. Just a thought. Page MA-14 under Repack front wheel bearing states to "Remove the screw plug from each steering knuckle and repack with lubricant." I guess if you fill it with lube from your gun it would settle out to about 3/4 full??? My question was slanted towards the maintainance side rather than the rebuild side.

Same for either rebuild or maintenance lube, and yes you can overfill it from the fill plug, in fact you can get it fuller that way than if it's opened up. When I originally purchased my rig, I decided to add grease through the plug hole until I couldn't add no more (wasn't aware of this site at the time and that I was only supposed to fill 3/4's full). Within a month I had birf soup oozing out of the knuckles. For whatever reason (heat expansion of the grease, stirring by the axle and birf, or whatever...) packing the knuckle full of grease WILL cause axle seal failure. You got to leave some room in there for it to move around.


Rookie2

 

[IdahoDoug]

Kalawang,

I'm not clear on if you actually have a problem here, or are mistaking normal grease accumulation on the spherical axle ends for a problem. This area is supposed to have a fine film of grease on it at all times and the movement back and forth leaves a line of crud like an eyelid blinking. That's normal. If it has a thin component that actively flows like gear oil then you've got a bad seal.

Along with the possibility of low quality seals, I'd also add two other candidates that are just as likely. 1 - a careless moment during install or failure to lube them or the install will ruin their molded lip edge. 2 - loosing track of, or not knowing the super thin metal shims for reassembly are supposed to be back in the same spot will change where the axle runs in the seal. Meaning the seals could be pulled into ovals from misalignment and quickly wear out on one side.

These are a couple reasons many find it useful to learn how to do the simple axle repack themselves personally. Lots of shops claim to know how to handle things like this with varying connections to reality.

DougM

 

[Kalawang]

IdahoDoug,

Very kind of you to comment on my query. I too doubt I have a real problem. I just don't like the look of grease building up at the axle ends. There's no gear oil mixed in there. It doesn't flow. Just hangs there as a disgusting mass that begs for cleaning. I'm betting that replaceing the grease that comes out will do no harm other than to my clothes.

The fellow who did my repack was Toy trained and was actually teaching two other mechanics on how to do the job and what tools were needed. He did each wheel in 3 hours and could have gone faster if he weren't teaching. I doubt there was an error. I try to get him for my 80 every time I go to that shop.

I compared the seals to the original and could not find a difference in material or size. Only price. It was also made in Japan. Anyway, I was suffering from a thin wallet that day so I took the alternative.

I may go for the OEM when I eventually make the change, but for now I'll do the grease thing for a few months and see what happens.


Kalawang

 

[TLCgrappler]

I think the knuckle wipers leaking some is no big deal. Since they "wipe", there is some leakage designed into it.

The axle seal that keeps the differential fluid out is a different matter. Having done only one birf repack, its clear to me that keeping a fluid-tight seal around a rapidly revolving axle is no small matter. Also, it seems to me that what the seal is called upon to do varies depending on how full the front differential is with fluid (you'd assume that any overfilling problem would have been taken care of by the location of the fill hole), and how much of the fluid is "pressing" against the back of that seal trying to get into the knuckle. The latter is going to be mightily affected by whether your truck is driven on steep sidehill angles. The more of that you do, the more likely it is that you'll work some differential fluid into the knuckle, IMO. Not based on any experience, but just on logical conjecture.

I suspect that many birf jobs are faulty and end up losing the little spring ring that holds the rubber of the seal tight against the axle. It looked to me when doing the birf repack like that spring would be easy to unseat if you weren't careful. That wouldn't help, of course.