Differential seal question (1 Viewer)

[DoctorJay]

So tonight I'm pulling into the garage, and there's a big puddle of gear oil under where the rear diff would be. I looked under the truck and there's a leak from the part where the driveshaft goes into the diff, I'm thinking it's a bad seal.

Several questions:

1. How involved is it to replace the diff seal? I'm thinking about new shocks (Bilsteins); would it be wise to replace these at the same time?

2. Will I damage the diff by driving it 10 miles to the mechanic?

3. Did I damage it by driving it 12 miles to work and back?

3a. Could the switch to Mobil-1 diff oil in January have anything to do with this?

4. How much is this going to cost? If you're playing along at home, I've owned my beloved LC for 14 months, and spent $4500 on it in that time ($900 brakes, $1600 90K, $2000 fuel injectors). It has now eclipsed my 1988 Prosche 911 as the most expensive vehicle ever owned. I really love this thing, it's far and away the nicest vehicle I've ever had. I'm just developing trust issues because I keep winding up in my wife's Honda.

 

[spressomon]

Bummer...you definitely have not had a good LC experience! The pinion seal can be replaced without pulling the diff (assuming the pinion shaft is not scored). You'll need to drop the rear diff side of the drive shaft and you will also need two different kinds of pullers assuming my '99 is the same as your '01...which I am relatively certain it is but maybe someone with an '01 can verify to 100%... (1-flange puller and 1-seal puller). PM me your e-mail address and I can e-mail you the FSM pages for this.


Strange it would start leaking. Did something (wire, rope, etc.) get wrapped around it by chance?

Pull the top diff filler plug and try to determine how much lube you have left. Worst case install HD diff lube (90/140...for the thicker viscosity) to get you to your mechanic (assuming it's not pouring out as fast as you pour it in ).

 

[matt 105]

Maybe this would be a good 1 for the FAQ?- with pics. - next time someone does it.
Seems to come up often enough.
Checked your diff breather?
Was your diff overfilled?
Can you move the pinion companion flange up and down?
Sometimes the leak is down the splines.
Never doen a UZJ - only HZJs - 105s, 80s, 7x, 4x etc, but assuming its the same, you'll need a hammer and a pin punch, a big screw driver and 2 x 14mm spanners, and a 30mm (1 and 3/16) socket, ....and a liter of oil to top up. Some sealant too, if your keen. Some ppl like to use a new nut, as well.
Havnt used a puller before.
Allow 1/2 an hour to do it on your front lawn.
Hope this helps

Matt

 

[matt 105]

Thought I had 1 here.
A 105 uses a BH6832E.
Toyota P/N 90311-41009
Regards

Matt

 

[DoctorJay]

Thanks for the input, guys. Spresso, thx for the offer on the FSM pages. I'm going to wind up at the shop again for this one, though. Assuming it's the pinion seal, they say $380 P and L. I called another dealer and she said 1.5 hrs labor (@$88/hr) and $10-15 for the part.

You insiders (lexusben) have any idea which is correct? I'm making some more calls to find out.

As an aside, if there were a local DIY shop (like they have lifts and tools, etc) where I could rent a slot and do the work, I would tackle this. In my hands, though, it winds up being 4 trips to Sears to buy tools, sealcoating my driveway with diff oil, and lying on my back and banging my head every time I sneeze.

 

[spressomon]

To answer the second part of your #1 question above: The only overlap of labor when doing the two jobs would be lifting the rig. Having said that the challenge when replacing the rear shocks is the upper mounting nuts: Tough to access (especially on the exhaust/muffler side)...and I, since they were very rust corroded, needed to cut the OEM's off (removing is relatively easy compared to installing/tightening the upper rear shock nuts...assuming you have some basic tools).

 

[DoctorJay]

To answer the second part of your #1 question above: The only overlap of labor when doing the two jobs would be lifting the rig. Having said that the challenge when replacing the rear shocks is the upper mounting nuts: Tough to access (especially on the exhaust/muffler side)...and I, since they were very rust corroded, needed to cut the OEM's off (removing is relatively easy compared to installing/tightening the upper rear shock nuts...assuming you have some basic tools).

thanks. When I saw the puddle I had visions of them dropping the rear end, but it doesn't sound like that's the case. In fact, one of the shops thinks it may just be a plugged breather tube. We'll see....

 

[spressomon]

thanks. When I saw the puddle I had visions of them dropping the rear end, but it doesn't sound like that's the case. In fact, one of the shops thinks it may just be a plugged breather tube. We'll see....

Not coming from direct experience with your issue; however I would think a plugged diff breather would result in a slow seep type of leak...will be interested in hearing their diagnosis.

 

[matt 105]

Howdy,
Ive just read your other thread, and seriously think you should do this youself.
If R/R rear pinion seal took me 1.5 hrs, someone would want to know why.
If it took 4 hours, - I would get the sack!
Check the breather first - when you pull the hose off the diff - can you hear air escape?
Check the levil cold,- how much oil have you really lost?

Matt

 

[sleeoffroad]

We will only replace a pinion seal with the third member in the truck, if we explained the possible causes to the customer. You have no way to confirm that you have the right pinion pre-load when you do it on the truck. Yes, they explain how to do it in the FSM, but it is still a gamble. If you loose your pinion pre-load, your diff is not going to last very long.

We would ideally pull the diff, do it on the bench so that we can verify the pinion preload with a torque meter.

 

[DoctorJay]

Resolution

Not coming from direct experience with your issue; however I would think a plugged diff breather would result in a slow seep type of leak...will be interested in hearing their diagnosis.

Diagnosis: plugged breather tube. They charged me for parts only, no labor (quickie job) and it came to about $15. And they washed my truck, too, so now it's shiny again. They said the differential oil level was fine, but this makes me nervous still. Can/should I check this myself?

Thanks for all the input here guys. I've found that it's much easier to deal with these shops if I understand the steps involved in the process before we speak. I did speak to the service manager about the ASM who quoted 4 hours on the job. He was obviusly disappointed that his guys quoted that time, he said there's 'no way' it should ever take that long. My impression was that he had no idea that his guys were coming up with numbers like that. I'd also speculate that when they hear "Land Cruiser" they assume (generally correctly) that the person on the phone has no idea what goes into these jobs, has money, and won't question their judgment. It's brinskmanship, and I can now honestly say that this site has saved me about $400 on this one. I'm going to go buy my star.

 

[e9999]

yea, good job, and good call on the star!

 

[spressomon]

Diagnosis: plugged breather tube. They charged me for parts only, no labor (quickie job) and it came to about $15. And they washed my truck, too, so now it's shiny again. They said the differential oil level was fine, but this makes me nervous still. Can/should I check this myself?

Thanks for all the input here guys. I've found that it's much easier to deal with these shops if I understand the steps involved in the process before we speak. I did speak to the service manager about the ASM who quoted 4 hours on the job. He was obviusly disappointed that his guys quoted that time, he said there's 'no way' it should ever take that long. My impression was that he had no idea that his guys were coming up with numbers like that. I'd also speculate that when they hear "Land Cruiser" they assume (generally correctly) that the person on the phone has no idea what goes into these jobs, has money, and won't question their judgment. It's brinskmanship, and I can now honestly say that this site has saved me about $400 on this one. I'm going to go buy my star.

Great! Checking your rr diff fluid is easy...just pull the upper plug (22mm?...I can check the exact size for you when I get home)...when the truck is sitting level/on the ground the diff fluid should be just below the bottom of this bolt hole. If it was leaking that much before they fixed the breather and they didn't refresh/add diff fluid it might be worth checking.

 

[KathmanduCruiser]

Oh, Man!

I am glad to hear how this resolved.

After the last unexpected expense you had to incur on the fuel injectors, you deserved a break. Thank goodness.

Was it the same mechanic who did the cylinder jobs for you?

Diagnosis: plugged breather tube. They charged me for parts only, no labor (quickie job) and it came to about $15. And they washed my truck, too, so now it's shiny again. They said the differential oil level was fine, but this makes me nervous still. Can/should I check this myself?

Thanks for all the input here guys. I've found that it's much easier to deal with these shops if I understand the steps involved in the process before we speak. I did speak to the service manager about the ASM who quoted 4 hours on the job. He was obviusly disappointed that his guys quoted that time, he said there's 'no way' it should ever take that long. My impression was that he had no idea that his guys were coming up with numbers like that. I'd also speculate that when they hear "Land Cruiser" they assume (generally correctly) that the person on the phone has no idea what goes into these jobs, has money, and won't question their judgment. It's brinskmanship, and I can now honestly say that this site has saved me about $400 on this one. I'm going to go buy my star.

 

[DoctorJay]

Oh, Man!

I am glad to hear how this resolved.

After the last unexpected expense you had to incur on the fuel injectors, you deserved a break. Thank goodness.

Was it the same mechanic who did the cylinder jobs for you?

Me too, brother. I've had a bit of a run of bad luck with those injectors, and I was sure ready for something to be cheaper than I expected. Different shop this time. The guys who did the other 7 injectors did fine, but they're 15 miles from my house. I would've taken it back there, but at the time, all I knew was that my diff was leaking and I didn't want to risk toasting it on a long drive, or wasting 5 hours waiting for the tow truck and escorting him there.

 

[ShottsUZJ100]

Here's a dumb question:

OK....the tube was clogged so the seal began to leak. By unplugging the breather the seal will no longer leak? Really?

 

[Dandon]

Here's a dumb question:

OK....the tube was clogged so the seal began to leak. By unplugging the breather the seal will no longer leak? Really?

I understand the seals are not designed to withstand pressure. That's why the diffs need to have vent tubes. If these are clogged, then the hot air inside the diff expands and, having no other way to alleviate prssure, forces the oil through the seal. With an open vent, the inner pressure and atmospheric pressure are always equal.

 

[Letsgomoreplaces]

agreed

yeah, what he said. Even if you have done 1000's of diffs, its still a gamble that you will have proper preload on the pinion bearings w/o a full tear down. If you have too much preload it will smoke the pinion bearings quickly as well.

We will only replace a pinion seal with the third member in the truck, if we explained the possible causes to the customer. You have no way to confirm that you have the right pinion pre-load when you do it on the truck. Yes, they explain how to do it in the FSM, but it is still a gamble. If you loose your pinion pre-load, your diff is not going to last very long.

We would ideally pull the diff, do it on the bench so that we can verify the pinion preload with a torque meter.

 

[LEXUSBEN]

We will only replace a pinion seal with the third member in the truck, if we explained the possible causes to the customer. You have no way to confirm that you have the right pinion pre-load when you do it on the truck. Yes, they explain how to do it in the FSM, but it is still a gamble. If you loose your pinion pre-load, your diff is not going to last very long.

We would ideally pull the diff, do it on the bench so that we can verify the pinion preload with a torque meter.

I agree as well.

That being said. I have done hundreds of pinion seals in the car, Trucks, old tercel wagons, l/c's, and never had a problem. True you can't check the pinion preload with the diff in vehicle, but you can compare before and after for a close estimate. Also reuse the nut, don't put a new one on. Usually you can reuse it once, this way you can stake the nut in the exact same spot or maybe just a hair tighter.

Jay - the time for the pinion seal in the vehicle should be 1.5 + the seal. The 4 hour estimate is high, unless they are quoting pulling the 3rd and checking the preload, then its a deal.

 

[ShottsUZJ100]

I agree as well.

That being said. I have done hundreds of pinion seals in the car, Trucks, old tercel wagons, l/c's, and never had a problem. True you can't check the pinion preload with the diff in vehicle, but you can compare before and after for a close estimate. Also reuse the nut, don't put a new one on. Usually you can reuse it once, this way you can stake the nut in the exact same spot or maybe just a hair tighter.

Jay - the time for the pinion seal in the vehicle should be 1.5 + the seal. The 4 hour estimate is high, unless they are quoting pulling the 3rd and checking the preload, then its a deal.

Hey Ben....can I hijack for one quick question? What does book say for labor hours on a rear main seal in an LX450. 450 not 470. End hijack. And thanks!