Dying front diff in my 2006?

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I did put cross-member in last. Don't recall if a actually support differential axle tube on DS, after front and rear mounts were in. I suppose one could do with cross member in, which may aid in holding up back side. It may make wrestling in position a little more difficult.

I took cross member out to de-rust. After looking at few cross members, I saw rust in same spot on each. Either these are moving around rubbing off paint, or Toyota is leaving as bare metal. If they are leaving as bare metal it would be for reasons of holding in place by "clamping force". If that's the case it's not working. Toyota does not sell the cross member alone. It comes with frame portion of mounts ~$500, which would need cutting out and welding in. So I elected to clean up and paint with POR-15, both surface (frame & cross member) as you can see. I then added ~5lb when torquing the four bolts & nuts. Replacing all the bushing, stops & mounts really tightens up the differential nicely. But if cross member moves around one my still get some shifting or driving metallic click/clunk sounds.

For simplicity I use (all - (oil, gear lube, grease and ATF)) M1 gear lube 75W-90 in all gear boxes. I find the Transfer case lube turns dark at ~20K, front diff ~25K and rear diff ~35K. I set 25K miles flush for transfer & front diff.
 
I lowered the crossmember with the diff because I thought it was easier that way. I then put the cross member back in the truck while I’ve been driving it some in the meantime. I’ll pull it out today and inspect for wear at the contact surfaces.

I’ve been debating going under my truck with some POR15 to neutralize the surface rust from her life in the Midwest but I know I’m opening up a can of worms. I will get to it, but maybe not until spring. Not much salt here in southern Oregon where she will spend her future life. Also, on my truck, I’m less concerned about the massive metal structures than I am about the seized fasteners and moving parts and mated surfaces (like this crossmember). I can’t POR15 most of these interfacing parts, so I think the only solution is to treat with anti-seize or grease or loctite as necessary, as I encounter each one. I’m replacing all hardware as pm when it looks like I may have issues with it.

@2001LC , have you examined your crossmember on this truck since the POR15 treatment? How has it held up? Has the POR15 had any bonding effect on the surfaces making them difficult to separate?

For simplicity I use (all - (oil, gear lube, grease and ATF)) M1 gear lube 75W-90 in all gear boxes. I find the Transfer case lube turns dark at ~20K, front diff ~25K and rear diff ~35K. I set 25K miles flush for transfer & front diff.

Thank you for this info, it’s very useful! I know that this may vary depending upon use so maybe I’ll vegin checking mine around 20k and take note.
 
If yiur driving with out your front diff- and axles, what have you used to cover the back side of the knuckle spindle bearings to keep dust-dirt-water and debris out?
 
I just stuffed a rag in there. I’ve driven maybe 40 miles this way, but I can see it has attracted some dirt....

I’m about to rebuild my wheel bearings with all new oem as part of my reassembly. Wheel bearing kit from @cruiseroutfit , new oem drive shaft assemblies (CVs), new flanges, flange gaskets, dustcovers, etc. I’ll have my old flanges machined in case I have future issues up front.

Also new diff mount stoppers & cushions. New sway bar links. It’s all been a bit neglected by P.O. The truck’s new to me so I consider it all part of the ‘getting to know you’ process.
 
I lowered the crossmember with the diff because I thought it was easier that way. I then put the cross member back in the truck while I’ve been driving it some in the meantime. I’ll pull it out today and inspect for wear at the contact surfaces.

I’ve been debating going under my truck with some POR15 to neutralize the surface rust from her life in the Midwest but I know I’m opening up a can of worms. I will get to it, but maybe not until spring. Not much salt here in southern Oregon where she will spend her future life. Also, on my truck, I’m less concerned about the massive metal structures than I am about the seized fasteners and moving parts and mated surfaces (like this crossmember). I can’t POR15 most of these interfacing parts, so I think the only solution is to treat with anti-seize or grease or loctite as necessary, as I encounter each one. I’m replacing all hardware as pm when it looks like I may have issues with it.

@2001LC , have you examined your crossmember on this truck since the POR15 treatment? How has it held up? Has the POR15 had any bonding effect on the surfaces making them difficult to separate?



Thank you for this info, it’s very useful! I know that this may vary depending upon use so maybe I’ll vegin checking mine around 20k and take note.
I've not examined since painting cross-member and frame with POR-15. I did give POR-15 gloss days to cure and both areas where rock hard, so I don't think they fused together. I've played around with the stuff a bit now, and can say it's more like a plastic then a paint and cures fast.

Good plan to keep tackling rust as you go! But if you see to much or holes from rust. Well, I'd then find another rig to restore, but that's me! I hate rust!!!!!!!!!!!!
I just stuffed a rag in there. I’ve driven maybe 40 miles this way, but I can see it has attracted some dirt....

I’m about to rebuild my wheel bearings with all new oem as part of my reassembly. Wheel bearing kit from @cruiseroutfit , new oem drive shaft assemblies (CVs), new flanges, flange gaskets, dustcovers, etc. I’ll have my old flanges machined in case I have future issues up front.

Also new diff mount stoppers & cushions. New sway bar links. It’s all been a bit neglected by P.O. The truck’s new to me so I consider it all part of the ‘getting to know you’ process.
I believe what @abuck is referring to is the axle bushing (brass) and needle bearing. These are exposed once front drive shafts (AKA CV's) are removed, sitting in back of steering knuckle. When I doing wheel bearing service for the first time on any rig with high mileage, I like to pull Knuckle and service as well

I assume the rag is stuffed in here:
PS wheel bearing and knuckle tear down 043.JPG
Here other side where spindle is which wheel bearing fit over.
PS wheel bearing and knuckle tear down 051.JPG
 
Yes, I wasn't planning to do that, but now that I see your photos of the nice clean knuckles, it's on my list .... I am in the process of re-reading the FSM pages as we speak.

After looking at few cross members, I saw rust in same spot on each. Either these are moving around rubbing off paint, or Toyota is leaving as bare metal. If they are leaving as bare metal it would be for reasons of holding in place by "clamping force". If that's the case it's not working. Toyota does not sell the cross member alone. It comes with frame portion of mounts ~$500, which would need cutting out and welding in. So I elected to clean up and paint with POR-15, both surface (frame & cross member) as you can see. I then added ~5lb when torquing the four bolts & nuts. Replacing all the bushing, stops & mounts really tightens up the differential nicely. But if cross member moves around one my still get some shifting or driving metallic click/clunk sounds.

My crossmember has the same issue:

DAE664F3-3898-4FBE-85B2-BE21B4070A32.jpeg


Not just on the inside face but also where bolt heads and washers sat on the outside face.
 
Reading through the links in my signature and the links within them, you'll find lots of stuff that I hope will be useful in helping you prepare.


Some tips:

When replacing Front Drive Shafts (FDS), use new (best practice) oil seals, applying gear oil to install. There is a new snap ring that goes on FDS inner axle, before inserting into differential. Lather snap ring with grease to hold in place, pointing open end of snap ring down. Then grease lip of seal before inserting FDS into differential. Carefully guild FDS into seal, twisting shaft back and forth a little to line up teeth. Once about 1/4 to 1/2" from being fully seated, use motion of CV to snap axle into place. Look to see that dust shield has seated just inside differential. Also try to pull out to make sure it's seated. Oh be very care with both dust seal and dust covers at either end, they bent very easy. Bent them back if they do or they'll rub.
New install (4).JPG

Properly seated front drive shaft with dust cover just inside of differential axle tube.
New install (6).JPG


Reading the FSM can be confusing, but it means what it says. The torque on adjusting nut of wheel bearing is only starting point. Read it with that understanding and it's clear. When doing the wheel bearings there are two key to a good job. First setting breakaway preload with a spring scale (AKA pull scale or fish scale). After torquing locking nut to 47lb I usually see about an increase of 2lb more on spring scale, so don't set preload (with fish scale) to more than 13lb when doing your adjust nut.
Wheel bearing Preload & snap ring gap 1.JPG

Wheel bearing Preload & snap ring gap 2.JPG

Second is outer axle to hub flange snap ring gap, set it very tight by the book. Pull your axle out very hard to press out grease, I use a clamp set-up.
01 LC wheel hub flange 002.JPG

Oh and don't pound on hub flange, only use brass dowel on studs to free cones washer. Good idea to get new cone wash to mate with new hub flange.

BTW did you notice my rig is held up with nails for jack stand pins,,, SPOOKY....... LOL
 
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Thank you @2001LC ! I have read through your posts a few times, especially here:

How'd bearings & races look after cleaning?
What grease did you repack with?
What grease used for axle bushing & needle bearing?
How much torque did you use on adjusting nut?
What was snap ring gap?
Each lock washer tabs can only be safely bent once.
I'd flip claw washer so smoothest side in or replace with new.

I've not yet had a problem with bearings being too tight, but have seen many issue when loose. I really wouldn't do a wheel bearing service without a pull (fish) scale, or it is just guessing.

I've found the older the bearing, the higher the torque needed to get the proper breakaway preload. I've seen from 23ft-lbf to 63tf-lbf torque just to get 9.5 - 15lbf on breakaway preload using a fish scale on used bearings (100k to 200k miles).
__________________________________________________

On this bearing service job, I found damage on outboard front drive shaft dust cover seals, hub flange teeth and excessive snap ring gaps of 0.60mm during disassemble. Loose wheel bearings cause chatter which is evidenced on claw washer scoring. This chatter then starts wearing on all components widening snap ring gap and wearing teeth of hub flange and axle. If not corrected the damage will extend too other parts.

On this rig pictured below, the loose wheel bearing damage was exuberated by not balancing tires regularly/properly and worn steering rack bushing. The road vibration and wondering was really bad, and made it unsafe to drive, now it's drives smooth and safe as new.

Here's a look at back side of knuckle, where axle bushing and needle bearings are located:

View attachment 1251310
There are easy fast ways to grease the axle bushing & bearings without removing knuckle:
Slee - Spindle Grease Tool
How to lubricate front axle shaft bushings?

I also like removing the knuckle dust cover if corroded in speed sensor area or my first service of a rig. So I can then inspect & clean out and then grease with marine grease, leaving drain hole at bottom open and clean. I put a thin layer of grease on all contact points included those of gasket, or any exposed metal. This stop corrosion, makes for better seal, easy removable and cleaning next servicing as it protects. I've gotten more and more liberal with marine grease over the years. I do wipe off excess, without using a degreasing during assemble.

View attachment 1251292
View attachment 1251289


I've replaced or even swapped hub flange of PS with DS to help tight up the back lash of hub flange to axle teeth.
Here's the teeth of a hub flange I needed to replaced (~$50 each).

View attachment 1251311

I reuse cone washer & hub flange nuts (FSM states not reusable), provided they pass inspection after cleaning. I then grease cones washer and use blue loctite on nuts. I find using a puller with clamp (clamp on knuckle in back, not dust cover) to pull axle up tight against axle bushing, very helpful to get good gap reading. The gap was .23mm on this job, so I replace snap ring with next size up (2.4mm) to get a very tight gap of ~0.03mm. Once gaps is over .2mm maximum with thickest snap ring (2.8mm) available, parts must be replaced. Here a list of possible parts that may be needed to get proper gap: claw washer, bearing & race, axle bushing, hub flange, axle (front drive shaft), spindle (knuckle). That is also a list of what loose wheel bearing breakaway preload can damage over time.

View attachment 1251313
Placing a jack under LCA, lifting to align front drive shaft is helpful. The key is to really pull out the axle tight and settle any grease on back side axle bushing area. It is not possible to have a snap ring gap to tight.

I also use marine grease on wheel hub to wheel contact points. You're looking at my LC with 165K miles on the hub. Notice no corrosion or rust at mounting points of hub.

Note: Never bang or pry on the hub flange to remove. Use a brass dowel to hit end of studs (per FSM), then grab cone washer with a pair of channel-locks or pliers to pull out. Some penetrating oil and/or heat can be helpful on those really stuck cone washers.

Check out that jack stand held up with a pin (nail), it's older than me, and I'm older than dirt...LOL
Safety first right!

But also here:

Options:

1) Remove front drive shaft & steering knuckle as one complete unit. This may be faster but you'd end up tossing what may be a lot of good parts. Most expensive option.

OR

2) Cut off tip of axle & hub flange.
3) Grind off weld: Remove just enough to allow axle to slip back out of spindle without obstruction of weld.

Your steering knuckle, axle hub and even wheel bearings may be ok. Until you take apart there is no way to be sure.

Each side that's welded, at minimum will need:
Front drive shaft (with new inboard snap ring).
Lock washer.
Axle hub flange gasket
Axle hub flange.
Axle hub cone washers (may be heat damaged or scored)
Axle hub nuts.
Axle hub flange Snap ring. (outboard)
Grease cap.

Plus any seal that are not serviceable.

This picture you can see how far axle comes out past spindle threads of steering knuckle. The rubber ring on axle is not part of assemble, it a Slee - Spindle Grease Tool seal form Axle needle bearing & bushing greasing tool.
View attachment 1372386
In this you can see wheel hub on steering knuckle with axle coming through steering knuckle spindle.
View attachment 1372390
Testing preload:
View attachment 1372387
Checking snap ring gap
View attachment 1372391


View attachment 1372377

I got a thickness gauge to check for correct snap ring thickness, a spring gauge for setting preload, new cone washers and flange gaskets, and a Slee spindle grease tool. I have new axle seals as well, but my differential came with one pre-installed from JT (on the right side). I checked with a straightedge and it was dead flush with the rim of the housing. I will put a new one in the axle tube end. I now have an extra brand new right side seal and another with maybe 100 miles on it that the dealership had just put in.

I may not drop my lower ball joint and remove the knuckle because my abs sensors are completely fused in but still functioning. (The dealership tore one in half then told me I’d need a new one when I come back for diff replacement. I guess they didn’t think to unclip top of wire in engine bay...) I can easily deal with lower ball joint at a later time if need be.

I plan to clean out spindle bearings as well as I can with brake cleaner then give them a light coat of grease. Once spindles are in I’ll pump them full with the Slee tool. Is this proper procedure?
 
IIRC Some of that was from an extreme case where a member found his axle welded to hub flange.

I've seen a few wheel speed sensors housing cracked. Soaking with penetrating oil over a night or two, then taping out with wooden dowel from inside may save the good one. I've seen used OEM wheel speed sensors or aftermarkets for ~$50, as alternative to $~150 new.

Brake cleaner is ok in a pinch. But solvent followed by higher pressure water then blown out with high pressure air does a much better job at cleaning bearings. They're so clean they must be greased as soon as dry.

The Slee spindle greasing tools is great for a quick job, where axle is has not been removed. But I feel it better to press grease into needle bearing with fingers while axle out, leaving cavity of spindle free of grease (air pocket). It's not a big deal, but like when doing the wheel bearing we do not want the hub cavity completely full of grease, we need some air space. If completely full of grease it will retain more heat, air pocket aids in the heat dissipation. So save your grease and the tool for subsequent wheel bearing service where axle not removed.

Good luck and have fun, you've a lot of work to do.
 
-Yes, but still helpful bits in there

-Thank you, I hope not to replace it until it stops working

- Good, thanks I will try this, maybe while still on the truck (I know, lots of messy solvent & water back in my face but I think it’s easier than messing with the wheel sensor at this time.)

- Okay, good to know. I’ll follow the fsm on this

Good luck and have fun, you've a lot of work to do.

Yes! It’s exciting for me to do this work. I haven’t done much other than suspension upgrades before on my Tacoma, so it’s all new. Lots of learning! I’ll update along the way with pics to help any who follow....

Thank you all for your help and advice, without it I’d likely never get this done or have the confidence to tackle it.
 
Started this a couple days ago, a little bit each night after my family goes to bed. Here’s the 12 and 6 play in my wheels:





My drive shafts are already out, but dust caps back on. After I loosened the flange nuts, I used a screwdriver to pop the first cap off and the whole flange came loose. I pulled the cone washers out by hand:

29C1C47F-8FE5-4E19-A799-DBB6A8092E38.jpeg


It looks like someone prior to me used a nail punch instead of a drift in the bolt ends to release the cone washers:

1110F361-4117-41EA-BFD3-5C136AB861F6.jpeg


Maybe it was the same mechanic who tightened the locknut with a chisel:

DEE75235-7C48-442C-B958-302CE6E503EE.jpeg


The adjusting but spun off by hand, I didn’t even need a wrench:

E103BD78-1AB2-430A-A3B1-BDD8B39DE542.jpeg


And the back of it was scored where it’s been wearing against the claw washer. Is it worth replacing or flipping this adjusting nut, it appears one sided?

3A4A22B7-CF44-42CC-BE62-F0A20001F2F6.jpeg
 
The claw washer shows severe wear on both sides:

D40DA8A0-A0A5-495D-BE61-494F67A5BF44.jpeg


79ACE7AC-A91C-4E48-B870-AEF8B9C37336.jpeg


And this oil seal was very stuck:

6E62A868-F903-48B2-B017-D187FF73038B.jpeg


I destroyed it trying to remove (I doubt it was already this way):

F298913E-8EFB-448F-A9BD-74462FA0BE44.jpeg


The outside face of the inner wheel bearing also shows wear where it contacted the oil seal:

A532A64E-2DEF-4802-B198-9B586C2A1A4B.jpeg


The FSM suggests a hammer and drift to remove bearings. Mine just about fell out. I pulled them out with two fingers, they were just loose in there. All the grease was dark black except deep in the recess between inner and outer bearings I found some still pink. I have no idea when this job was last done.

This is all drivers’ side. I’ll open up the passenger side tomorrow. Except for chiseled lock nut and worn adjusting nut (maybe I should order these just to start fresh) I have all the replacement parts ready to go.
 
The inside of the hub itself actually looks really good, like new. What is now concerning me more than the hubs is the knuckles. I already knew the abs sensors weren’t coming out alive but now I can see why. Here’s a sneak peek:

7CB5F153-7227-4AA0-8202-53618C98D688.jpeg
74A02AD6-B832-4BDB-8DF9-AD35DE8A48C0.jpeg
3ACB43D7-A55D-4056-9C4F-44DEF45D637B.jpeg


The spindle bearing and bushing don’t look horribly bad yet but given the way things are going, I’m not optimistic. I also drove it to the body shop and back with the shaft out and rags stuffed in so that likely didn’t help it....
 
SlowB

The wheel bearings will fall right out, its the races the bearings sit in that need to be tapped out when replacing bearings. If you are simply regreasing and reusing same bearings, inspect but leave races in.

That black grease look like Moly fortified grease- not what you want to use on high speed roller type bearings. You may want to clean off the race and closely inpect the roller bearings for scoring-wear as moly will accelerate wear. I would thouroughly clean all grease from the hub/rotor and repack properly with M1 or comparable. Use a bearing packing tool to squeeze the grease into the rollers.

The knuckle can be removed with the sensor attached, just remove all of mounting points between the UCA and on the knuckle. To keep it out of the way and protect the connector coil up the excess wire, put in a zip lock bag or wrapped in a towel and zip tie to one of the mounting bolt holes. I know 2001LC likes to remove them, but if they are stuck and you attempt to tap out, there is risk of damaging- and then you have more expense. Now you can fully clean the knuckle and spindle bearings- which from the looks- needs cleaning and regreasing.

When I see a tech who has used a chisel on the adjust and lock nuts I know the bearings could not have been preloaded or torqued correctly. First time I serviced mine, I found the same results.

Good luck with the rest of your job.
 
I use a wooden dowel to tap out hub oil seal, passed through from the front.

I use the same wooden dowel to tap out the ABS (wheel speed sensor), never broke one yet. But I don't deal with much rust here.

I'd go ahead and replace the claw washer, cones washers and any damaged nut(s).

Note: I like to place the flat side of nut against claw washer, gives more surface area contact to it.

Tip: Bearings are matched to their race, don't mix up.

Here's my hi-tech grease tool, many many many years in the making:;)
032.JPG
034.JPG
 
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If you don't want to punch at the oil seal from inside the hub or pry it out like you did, there is a trick you can use to remove the backside oil seal and reuse it. Steps are listed below. You're essentially pulling the rotor off the knuckle and using the inside bearing to pop it off.

1. Remove outside axle nut and lock washer
2. remove inside axle nut and claw washer
3. remove small outside bearing
4. reinstall ONLY the inside axle nut. Spin on so all threads are engaged.
5. Grab rotor at 9 and 3 o'clock and slide it past outer race and off knuckle towards you. You'll feel the weight of the rotor in your hands as it slides off the knuckle.
6. With one strong motion pull the rotor to you and the inner bearing will pop the seal out.
7. Just like that Bob's your Uncle and the bearing and seal will be left resting on the knuckle.
 
Not picking on you @78f150tx, so please don't take offense.

There is a video floating around here which using the above trick to pop the hub oil seal off with hub and nut you've outlined. The guy was doing a rotor swap out IIRC. I saw so many things in video I didn't care for. So much so I though it to be a "how not to do" video. His method of seal removal risk damaging the inner race, bearing cage, axle tip teeth & snap ring retaining groove, butting surface for seal, spindle, nut and seal.

Then there is prying out "what a pain" and can damage more than just seal.

I don't typically reuse the seal but the wooden dowel is so easy and safe that all components condition are unchanged and takes no more time. Tap Tap Tap and they fall to the bench.
 
@SlowBuild I did see cone washer on your list. I highly recommend them with new hub flanges or if scored at all. Add a little grease to them and they'll come out easier next service.
 
@78f150tx thanks for your advice. A already got it off with @2001LC ’s method (wooden dowel) and it worked great.

There is a video floating around here which using the above trick to pop the hub oil seal off with hub and nut you've outlined. The guy was doing a rotor swap out IIRC. I saw so many things in video I didn't care for. So much so I though it to be a "how not to do" video. His method of seal removal risk damaging the inner race, bearing cage, axle tip teeth & snap ring retaining groove, butting surface for seal, spindle, nut and seal.

I saw this video posted in another thread but I didn’t even watch because of your reaction. I thought if I’ve never done this before it’s better not to learn it wrong. I think shortcuts are best for people who already know the long (proper) way. At least in my case....

That black grease look like Moly fortified grease- not what you want to use on high speed roller type bearings. You may want to clean off the race and closely inpect the roller bearings for scoring-wear as moly will accelerate wear. I would thouroughly clean all grease from the hub/rotor and repack properly with M1 or comparable. Use a bearing packing tool to squeeze the grease into the rollers.

I’m not sure if the grease was black to begin with or just really old. When I dig deep enough cleaning it out I find some that’s almost pink (maybe it was old pink never cleaned out thoroughly or maybe it turned black, either way it’ll be gone now):

496F4EC6-4277-43E9-825B-5DEAFE375608.jpeg


The passenger side looked a lot like the driver’s side:

5F3343B5-A937-4DD3-B4B7-2C5B8E551ED8.jpeg


E8CAFB12-85B7-4955-B281-4A441F5A75A5.jpeg


CEC57563-559E-4836-A416-1C8100B601CC.jpeg


820415EE-F5BE-431E-ACA7-7DDECC2236C4.jpeg


All these parts will be replaced (along with lock washers, which are well worn).
 
@2001LC , thank you I have all new cone washers ready to go in. Yes, there is scoring on the old ones. I plan to reuse nuts and flat washers. I am replacing bearings and races just because I already have them and I want to start out fresh. My old ones don’t look too bad to me but I don’t know how to assess.

I am getting a ball joint pulled today for LCA and TRE and I will clean up knuckle and assess. I don’t want to fight with spindle bearings trying to press them in and I don’t want to pay $500/side for new knuckles so I’m hoping I can just clean, grease, and reinstall. I’ll post photos when I get there.

A couple questions:

I pulled the brake dust shield and cleaned it up. There’s s bit of rust. Is this safe to paint with rattle can or POR15 or does it get too hot?

I will replace the ‘knuckle spindle oil retainer gaskets’, which have deteriorated, but what about the dust seals that go against the brake dust shield? I started to clean mine up and they’re completely bubbled with grease. I suspect this might be why my abs channel in the hub is so full of junk. The rubber rings look mostly intact but I’m not super confident in them. I think they should be replaced but they’re over $50 each. Any thoughts. I can clean them up and POR15 but I’m not sure about heat with this part so close to brakes and also I don’t want to really spend the time if I’ll end up just tossing them. Any suggestions? They both look like this:

AC422771-5C1E-451A-AAA6-D8DD4F7EF31C.jpeg
81FF4B4D-5B76-4479-A360-BC5501F0195A.jpeg
C9C38207-F58A-4333-8598-0A4C41C1DAC4.jpeg
 

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