Front Drive Shaft / Differential leak; Oil Seal & dust cover replacement

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Put a straight edge across the end of the tube. If the sharp rubber lip of the seal touches it, you are good. Any deeper and it will likely leak.
How about this, I think it touches, if not there will be less than one hair deeper.

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Yep- too deep

Theres a couple of ways to skin this cat. I think its easier to use the edge of the race as the reference point for setting seal depth. If you read back through this thread you’ll find some answers. The face of the seal (flat area) which is set even or slightly above the edge of the race.

See here

 
Yep- too deep

Theres a couple of ways to skin this cat. I think its easier to use the edge of the race as the reference point for setting seal depth. If you read back through this thread you’ll find some answers. The face of the seal (flat area) which is set even or slightly above the edge of the race.

See here

Thanks man, you mean the black arrow pointed seal edge should align or a little above the blue arrow pointed hosing inner edge, it this correct? I bought another two "cats", I am heading to pick them up, I believe I will do it right in another two chances...

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Yep- too deep

Theres a couple of ways to skin this cat. I think its easier to use the edge of the race as the reference point for setting seal depth. If you read back through this thread you’ll find some answers. The face of the seal (flat area) which is set even or slightly above the edge of the race.

See here

I think this time is about perfect. The inner race depth is about 5 mm, the seal this time from 4 points measurements about 4.75 to 4.92, means is almost flush and tiny above the race edge. It also proved that the outer edge of the seal will be about 1mm out of the tube as the sec pic shows.

Gee, this really requires a lot of patients...particularly when this work is done with jack stand, I have to roll on the ground from the front to behind of the LCA like a rat...

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I just reached there, I think what we talked "using a wood stick" as a drift will be difficult for this "tube/driver" side, because the lip of this side so small, maybe too small to stop the wood stick when punch on it..
This is where hard wood pays off. The 3/4 X 1 1/2 " does fit and catches the thinner lip of DS on diff. With soft wood, you'll not feel it catch the lip and over drive in seal..

These days I use Wit'send seal drive tool. keep reading and you'll see further down in this thread. Works very well.

In either the first seating of seal which was a little deep or second which was a little shallow. Those were both fine. That's the ~0.5mm -+ (1mm) I wrote about earlier. By looking at wear mark on old FDS, you'll see where seal was riding. You'll see the area seal rides on width, allows for movement in and out of FDS and then some.

Again; Key is square (level). So as you move your straight edge around to various points, provided your seal hit same point on straight edge always. You are squarely seated (perfect).

As much as you're concerned with every detail. It will be fine. You've done well.
 
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This is where hard wood pays off. The 3/4 X 1 1/2 " does fit and catches the thinner lip on DS diff. With soft wood, you'll not feel it catch the lip.
I finally use a 2 inch ID pipe for getting this done. But I do believe "wood tech" will work very nicely for the passenger side. Man..I am not handy like you...my hand has no such a good feeling about things... Anyway, thank you so much!
 
Whatever one can find around the house that works, is the perfect tool. I've used a number of different tools (stuff lying around the shop) to seat these over the years. The hard wood stick, has become my go to more than others.
 
Yes, works either side. 3/4' width X ~1/1/2" x 24" oak (hard wood, holds it's form for many seal jobs) stick is best. Oak hits inner shelve of diff, which is right were seal seats.

LH side, I work a bit faster. If I seat to far in, I pry back out. The LH seal has metal plate on back side and diff tube has center protrusion I angle off of, to pry back out seal to square off if i need to. RH side, I take more time to not over shoot (seating seal in to far), getting seat perfect first time.

Most important is seal must be seated squarely. If cocked-eyed, it will likely leak. If in or out .5mm -+ but squarely seated, it will likely not leak.

I've done more than I can remember. Not one has leaked.

Often guys get seal in okay. Only to knock out of alignment installing front drive shaft.


@2001LC Paul your videos are amazing. Thank you for posting them along with your detailed instructions and your process.
In this video you mention that the outer dust ring can bend if rested on the LCA. Well mine is bent a little. I actually think it came like that out of the box but maybe I did it when I tried to install the FDS.

I was wondering if you had any suggestions on bending it back? I still have my old FDS that I am going to practice on too.
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All that I've had ship in, where bent. These days I buy at my local Toyota Dealership "Groove Toyota". Not one has been bent.

I use body tools. A ball peen hammer and dolly. Dolly is just hunk of steel.
 
This is where hard wood pays off. The 3/4 X 1 1/2 " does fit and catches the thinner lip of DS on diff. With soft wood, you'll not feel it catch the lip and over drive in seal..

In either the first seating of seal which was a little deep or second which was a little shallow. Those were both fine. That's the ~0.5mm -+ (1mm) I wrote about earlier. By looking at wear mark on old FDS, you'll see where seal was riding. You'll see the area seal rides on width, allows for movement in and out of FDS and then some.

Again; Key is square (level). So as you move your straight edge around to various points, provided your seal hit same point on straight edge always. You are squarely seated (perfect).

As much as you're concerned with every detail. It will be fine. You've done well.

Just did this using the oak stick method and it went in pretty well. I did start it off with the oil filter socket thing to get it in just enough to where I could start tapping it with the stick. Took a bit of time, but it SEEMS good. I wrapped the stick in a could piece of electrical tape just for a little more protection.

Sorry I don't have any pictures, but what I did was feel around the edge of the seal before I pulled it out to get a feel for how it was seated. Original was seated just a touch above that rim so that's where I drove the new seal into. Still can't get the axle in though so I don't know if it's going to leak!
 
My passenger-side output-seal has been leaking on and off after I did CV-reboot. I add ~0.3qt of gear oil every ~1,000 miles. The plan has been to replace the seal once I have a good chunk of time for that.

Adding gear oil takes less than 10 minutes (put AHC into "high", slide under from the driver side, eyes and hands are conveniently just under the diff). With that, this temporary fix is turning into a routine now. I wonder though, am I damaging the front-diff by letting the fluid level to drop and driving around with 1.5 quarts instead of 1.8 quarts. Any opinion on this?

I've looked at the schematics of the front-diff, but couldn't tell if exact fluid level is important.
 
I tried out my new to me; Wits'end seal install drift tool today. Love it!

It fits perfect and very snug, which is critical on DS with it's very narrow seating shelf..
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I used a common scraper to clean away built up grim, from seating shelf. A critical step, to insure seal seats flush as drift seats on shelf. Then I made use of a very heavy hammer with extra long wooden handle. Holding hammer head in my hand and tapping on the seal drift with butt end of handle. Worked fast and seated perfectly.

It will be and even better tool, once Witsend has the long handle available for sale. As I'd like sit back out side wheel well and tap in. A 22" or 24" extension should do the trick. 20" would probable do with knuckle out. But for those time install is while knuckle in, the extra 2 to 4" would be nice.

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I tried out my new to me; Wits'end seal install drift tool today. Love it!

It fits perfect and very snug, which is critical on DS with it's very narrow seating shelf..
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I used a common scraper to clean away built up grim, from seating shelf. A critical step, to insure seal seats flush as drift seats on shelf. Then I made use of a very heavy hammer with extra long wooden handle. Holding hammer head in my hand and tapping on the seal drift with butt end of handle. Worked fast and seated perfectly.

It will be and even better tool, once Witsend has the long handle available for sale. As I'd like sit back out side wheel well and tap in. A 22" or 24" extension should do the trick. 20" would probable do with knuckle out. But for those time install is while knuckle in, the extra 2 to 4" would be nice.

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If my seal leaks then I’ll probably end up buying this tool as well. The oak stick worked okay but I can see how this would be so much better!

Fingers crossed it’s good for the next 250k!
 
Using the short cut it took me ~25-30 min to get axle out of tube. True to reports. I coulda been a little bit faster because I had to put the knuckle back on the UCA ball joint to get the tie rod end connectors off.

Now I am in and I so clearly got the seal in to far. When installing I was worried about not getting it in enough. I did lube the outside of the seal with gear oil before putting in, but it does not move freely.
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It sounds like it should be flush with the inner lip. where the clean metal stops way in the above picture. There also isn't alot of room to get a pry bar or screw driver behind the seal w/o leveraging against the inner tube. I will try some gentle things to try and back it out without damaging the seal, but if it doesn't work I will probably cover this up, get a new seal tomorrow and then snip out the old-new seal. Thoughts?

This right here is why my ASD-2 seal tool was developed. It works on ALL Toyota 4WD input seals. Its designed to bottom the seal out at the correct depth for both sides. I am out of stock for the moment but I have another big batch coming in a couple weeks.


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@NLXTACY My left IFS output shaft seal just started leaking. It did great for a year, trip to Colorado and back, but decided to start leaking this week.

I have the tool and the short extension. Is the long extension available? If yes, I need to order one right now.
 
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