FJ40 Front Axle (Birfield) Maintenance Question

[rstoddard]

How much tear down of the front wheel axels is required to inspect the CV joints for any required greasing or cleaning?

I don’t recall if the wheel bearings have been graded in 20 years. Maybe 10 years ago. There is no leaking, but I’d like to tear them down to check them, and grease them if needed. I don’t expect that the bearings will be bad. I’m just wondering what I need to be prepared to have to replace (seals, gaskets) in getting in there, and if ifs going to require a complete tear down of the knuckle. I hope I don’t have to go that far, but might wondering what the advise would be once I get into it. Should I plan for a full tear down?

Thanks for the advice/recommendations.

 

[DangerNoodle]

It will need a full knuckle teardown. It's pretty easy to do.

 

[rkymtnflyfisher]

Bout this far.

 

[3_puppies]

what year rig?

 

[vfrer]

to just get the birfs out you have to remove hubs and spindles at a minimum. you do not have to take the knuckles off but you may have to loosen the steering arms to pull them. if you just want to know if there is grease in the knuckle pull the square plug and stick a straw in and see if it comes out greasy.

 

[rstoddard]

what year rig?

1978

 

[rstoddard]

to just get the birfs out you have to remove hubs and spindles at a minimum. you do not have to take the knuckles off but you may have to loosen the steering arms to pull them. if you just want to know if there is grease in the knuckle pull the square plug and stick a straw in and see if it comes out greasy.

Yeah, I was thing that, but I think I'd like to tear it down and clean out the Knuckle and refill it. I didn't want to have to pull the Knuckle itself because I was concerned about messing with the steering, and the shims, and any pre-load measurements (if applicable). I'm not leaking anything, so I figured if I get in there and there isn't any sign of diff oil, I'd just clean it and re-grease everything. No good?

 

[brian]

there is a plug that can be removed and grease added as needed. no reason to pull everything apart to inspect unless you're bored. if the inner axle seal fails, you will see leakage as the seals are not intended to contain that runny of a lube.
wheel bearings are a matter of just taking the wheel hub off the spindle.

 

[rstoddard]

Bout this far.

View attachment 2960284View attachment 2960285

You are doing a helleva nice job. Hardly any mess!

I have the larger Birf's from the Toyota truck in mine, so they were a tight fit to get in. Seems like I had to grind some of the Knuckle housing to get them in.

I don't expect to have to replace the bearings, but I was going to use a different grease this time round.

Should I remove the Steering Arms so I can clean the bearings and re-grease them? If I do, do you have to set any pre-load on the steering arms? Will I need to re-align the front end?

 

[3_puppies]

Yeah, I was thing that, but I think I'd like to tear it down and clean out the Knuckle and refill it. I didn't want to have to pull the Knuckle itself because I was concerned about messing with the steering, and the shims, and any pre-load measurements (if applicable). I'm not leaking anything, so I figured if I get in there and there isn't any sign of diff oil, I'd just clean it and re-grease everything. No good?

If there is grease in there, thru the square plug and no signs of leakage, I wouldn't mess wiith it, but that is me.
if there is no significant leakage on the ball, just keep the shims together and install the same when re-assembling the knuckle.
if you are going thru all the trouble to get to the birf out, just do the entire project. myself, going that deep into the axle, I don't mess with cleaning the bearings, I just replace everything, for the cost of a knuckle kit versus my time to clean and inspect.

 

[rkymtnflyfisher]

Hardly any mess!

Not all is what it appears.

 

[PuKE]

Reawakening this thread.
I'm doing a complete tear down of my knuckles. 74 FJ40.
Is it okay to use a wire wheel and scotchbrite to clean the outer birfields? I used some scotchbrite and noticed scratches appearing.
Lastly, I noticed deep grooves inside in each direction (passenger side). Should I grind it down smooth? Or is this not a concern? There is no wear on the outer axle.
Thanks to all you fellow mudders in advance!

 

[SteveH]

@PuKE - the scratches looks like old trauma from your truck's history. I wouldn't worry about polishing or removing it. All this stuff is immersed in grease when operating, so getting it shiny clean (beyond removing old grease and any dirt) isn't critical.

 

[dazerb]

Reawakening this thread.
I'm doing a complete tear down of my knuckles. 74 FJ40.
Is it okay to use a wire wheel and scotchbrite to clean the outer birfields? I used some scotchbrite and noticed scratches appearing.
Lastly, I noticed deep grooves inside in each direction (passenger side). Should I grind it down smooth? Or is this not a concern? There is no wear on the outer axle.
Thanks to all you fellow mudders in advance!

View attachment 3879913

As long as you can get the races in there cleanly. The OUTSIDE of the ball is where the felts rub so you want that nice and smooth.

 

[POPO AGIE]

Reawakening this thread.
I'm doing a complete tear down of my knuckles. 74 FJ40.
Is it okay to use a wire wheel and scotchbrite to clean the outer birfields? I used some scotchbrite and noticed scratches appearing.
Lastly, I noticed deep grooves inside in each direction (passenger side). Should I grind it down smooth? Or is this not a concern? There is no wear on the outer axle.
Thanks to all you fellow mudders in advance!

View attachment 3879913

Mine also had wear marks and I had to take a die grinder to open mine up for RCV Birfield axle shafts.

 

[PuKE]

Thank You ALL!
I appreciate your input.
I LOVE this platform!!!