When to perform knuckle rebuild? mileage or year interval

Joined
Feb 23, 2016
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Sarasota, FL
I recently bought an FZJ80 from the original owner with complete service history going back to 2004. Truck currently has 125k on it and has been a city car/babied all its life. Last knuckle rebuild was only 20,000 miles ago. Although, that was 8 years ago.

I plan to take a trip from Florida to Chicago this summer for the 4th of July and am deciding if I should rebuild the knuckles. There is no clicking or leaking from the knuckles....only slight build up of road grim. Although, I do hear a clicking when going up the ramp in my parking garage (turning left) - not sure it this is more a bushing related issue.

I do need to replace the front brake pads, and if that means I should replace the rotors as well, then it seems as while I'm at it I might as well rebuild the knuckles.

Is the service interval for the knuckles based on years/mileage. The owner's manual does say every 24 month interval, but wanted to get everyones thoughts/experiences.

Thanks for the input.
 
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I usually check the steering arm studs for tightness, wheel play (pushing and pulling on the front wheel side to side) for loose bearings, leakage, grease level as stated above and brake caliper bolts.
 

inkpot

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Mileage, not time.
Leakage. Not time nor mileage. It took about 100,000 miles for my seals to start leaking bad, so that's when I serviced my knuckles. If you keep the diffs filled and the knuckles fill properly, then the only good reason to service the knuckles is if the birfs are making a lot of noise.
 

LS1FJ40

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Leakage. Not time nor mileage. It took about 100,000 miles for my seals to start leaking bad, so that's when I serviced my knuckles. If you keep the diffs filled and the knuckles fill properly, then the only good reason to service the knuckles is if the birfs are making a lot of noise.
This. My knuckles on my 93 leak like a sieve. Just haven't gotten around to it. Just check grease levels and add as needed.
 

NLXTACY

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X whatever on leakage.

But... I check my wheel bearings maybe once a month and I check the knuckles/hardware probably weekly. If I hear clicking when turning, well then it doesn't matter if it's leaking or not, I'm going in to take care of the noisy birf.
 
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I usually check the steering arm studs for tightness, wheel play (pushing and pulling on the front wheel side to side) for loose bearings, leakage, grease level as stated above and brake caliper bolts.
this, as part of your regular oil change routine. but if it not leaking, and not gunked up around the swivel seals then how does the grease level change?

mileage is a Goldilocks scenario. Has Pappa bear been wheeling it hard every weekend? or has mummy bear been hitting the mall?
 
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A while back I had oil, grease cross contamination. I rebuilt my knuckles but failed to realize that there was a groove on the axel where the axel seal rides. The new wipers I put in did not leak but the grease was getting washed out by the gear oil in the axel. Trail gear makes a offset axel seal with a spring holding the seal closed like an oem seal that grabs the axel out past the groove. Also if you wheel a lot it is a good idea to repackage your wheel bearings annually. This is just information your rig has less miles on it. But it's always good to get in there and check everything on a new to you rig. It's also good to know how to tear into a birfield.
 
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Joined
Feb 23, 2016
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Thank you all for the replies.....This one has definitely been a "mummy bear hitting the mall" for most its life and will probably continue that way for a while since I live down in Florida (wish there were mountains or even hills here). I will check the steering/suspension play and take some pictures of the knuckles as soon as I have a chance.
 
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You must check you wheel bearings after every "curb-wheeling" adventure.......

While I do not disagree with what @inkpot has to say on leakage, you should be OK UNLESS you check the front end parts and discover something is loose, rattling, or leaking. Overall, that's referred to as Preventive Maintenance.

You MUST perform some level of PM, and usually it is mileage based because it is a way to look at it.

However, one of the things that I WOULD change based on time, is the engine oil. After an engine has been run for any length of time, there are acids that build up in the oil. If an engine sits not operating and not circulation for a long period of time (a year +), then the acids get worse and will etch the bearings in the engine. The moisture from condensation does not go away and can make the issues worse. So, in that case, change the oil yearly. Just before storage (winter) as a minimum to remove as many acids as possible.

They refer to most of these as PM tables. It is a GUIDE based on usage that you SHOULD at least LOOK at the service of the parts to make sure they are still in spec.
 
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this, as part of your regular oil change routine. but if it not leaking, and not gunked up around the swivel seals then how does the grease level change?

mileage is a Goldilocks scenario. Has Pappa bear been wheeling it hard every weekend? or has mummy bear been hitting the mall?
In my experience the knuckles can't tell the difference between dirt and asphalt driving. If they are leaking because you've been driving on bumps of any kind, then something is seriously wrong with your abilities to make sure things are assembled properly
 
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You must check you wheel bearings after every "curb-wheeling" adventure.......

While I do not disagree with what @inkpot has to say on leakage, you should be OK UNLESS you check the front end parts and discover something is loose, rattling, or leaking. Overall, that's referred to as Preventive Maintenance.

You MUST perform some level of PM, and usually it is mileage based because it is a way to look at it.

However, one of the things that I WOULD change based on time, is the engine oil. After an engine has been run for any length of time, there are acids that build up in the oil. If an engine sits not operating and not circulation for a long period of time (a year +), then the acids get worse and will etch the bearings in the engine. The moisture from condensation does not go away and can make the issues worse. So, in that case, change the oil yearly. Just before storage (winter) as a minimum to remove as many acids as possible.

They refer to most of these as PM tables. It is a GUIDE based on usage that you SHOULD at least LOOK at the service of the parts to make sure they are still in spec.
Well....

Routine maintenance is what you described. It is not the same as preventative.

Also, I've run the truck up against, off of, and much more when it comes to curbs. That doesn't even touch on what I've done off road to the truck. By your knowledge I should check the wheel bearings daily? Hourly? Should I check them before I leave the restaurant from lunch today?

I'm with @Tools R Us and @inkpot so I'll check with them for a more expedient reply.
 
Joined
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Well....

Routine maintenance is what you described. It is not the same as preventative.

Also, I've run the truck up against, off of, and much more when it comes to curbs. That doesn't even touch on what I've done off road to the truck. By your knowledge I should check the wheel bearings daily? Hourly? Should I check them before I leave the restaurant from lunch today?

I'm with @Tools R Us and @inkpot so I'll check with them for a more expedient reply.
Sorry, I guess the sarcasm didn't come through........

If s***'s broke or leaking or loose, fix it. If you think you've run it long enough, take it apart, clean it and readjust it if you are so inclined. Otherwise, run it 'til it falls off, then drop back 20 and punt........
 
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Sorry, I guess the sarcasm didn't come through........

If s***'s broke or leaking or loose, fix it. If you think you've run it long enough, take it apart, clean it and readjust it if you are so inclined. Otherwise, run it 'til it falls off, then drop back 20 and punt........
Dammit man. There needs to be a sarcasm font.

Granted I laid it on a little thicker than you did...
 
Joined
Feb 23, 2016
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Sarasota, FL
Finally got around to checking the front end....everything seems to be pretty sound as far as the steering/linkages. Below are pictures of the knuckles. (First two should be driver, and second two passenger). What does everyone think of them? Also checked the brake pads and all were right around 5mm thick. FSM says min. thickness is 1mm. So, probably have a little to go. Does anyone know the new thickness of these pads?
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Joined
Dec 27, 2011
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Colorado
New brake pad thickness is about 10 or 11mm. From the look of those pics it seems like it would be a good idea to service the knuckles soon, I have seen far worse. It does look like you have some grease that is contaminated seeping from the knuckles.
 

Tools R Us

 
 
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The knuckles don't appear to be leaking, but almost empty, should be 1/2 - 3/4 full of moly grease. Check gear oil for level and contamination, my guess, has moly contamination, needs to be changed. Also confirm knuckle nuts torque at 71ft/lb.
 
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