RTH - knuckle preload too high

[leucadiacruiser]

Thanks to all who have posted the countless threads, pictures and videos on knuckle rebuilds. My fj62 was in dire need of a knuckle rebuild so with 'Mud was able to take this on myself over the last few weekends. I got a kit from Cruiser Outfitters and after a few weekends of clean up started reassembling the knuckles yesterday. Got driver side done up to the rotors - smooth - with knuckle preload at about
7 lbs. Passenger side has me perplexed and here is where I'm at. Preload on passenger side is currently at 20 lbs. using a fish scale. Here is what I've tried:

1. remove and reseat bearing races (used the freezer trick)
2. Started with two shims on top and bottom, then tried two on top, one on bottom.
3. double check bearings are packed with grease
4. Try again and torque to spec

And still at 20 lbs. pre load. From the countless threads I've read, I know 14 lbs. is going to be max. A few threads I've read say 'drive it and see'. I'd rather get it done while I'm in here and just wondering if I'm missing the obvious, which is generally the case Is this where the SST comes in because I haven't used one. Maybe that's the obvious. Thanks in advance.

 

[Dynosoar]

Do you have the wiper (Steel, Rubber, Felt) all bolted up? Check preload without the wiper bolted up.

Dyno

 

[leucadiacruiser]

Thanks @Dynosoar yes - no wiper. I just looked again at my old shims and they are substantially thicker than the ones in the new set. I put one of those on top with a new thin shim and with spec torque, preload now at 14 lbs so I'm going to go with it.

 

[Output Shaft]

Although the shims set bearing preload, they also set the knuckle alignment, so you can't just remove one of the shims to reduce preload. The knuckle will then be out of alignment.

You would have to replace both uppers and lower with equally thinner shims on both sides so that the alignment does not change.

 

[augirthedude]

Once assembled .... Load the knuckle by putting the weight of the vehicle on it . Like putting the floor jack under it ....once the weight of the vehicle is on the knuckle induce a shock load on the knuckle like a hammer strike . Remove the jack and retry the resistance test. if for some reason the races are not seated properly you will get an erroneous reading . Do you have the factory service tool to calculate the shim thicknesses ? It is pretty much pointless to do this job without this tool. Do you have all the correct thickness shims to arrive at the proper dimension that service tool designates..?

 

[leucadiacruiser]

@augirthedude looks like I'm looking for an SST Was hoping I could get away with plug and play.

 

[augirthedude]

Where are you located. I am in the ABQ New Mexico area and have the tools for this job

 

[leucadiacruiser]

Although the shims set bearing preload, they also set the knuckle alignment, so you can't just remove one of the shims to reduce preload. The knuckle will then be out of alignment.

You would have to replace both uppers and lower with equally thinner shims on both sides so that the alignment does not change.

Pretty much a wrench so I wrongly assumed shim it up, check preload and go. Would I have been better off using the old shims on both sides? Preload on my first side was fine with the new shims.

 

[leucadiacruiser]

Where are you located. I am in the ABQ New Mexico area and have the tools for this job

Awfully kind @augirthedude I'm in San Diego - I'll be able to track one down locally.

 

[Output Shaft]

Normally you can (should) use the original old shims with the new bearings.

 

[augirthedude]

I tried to do a knuckle rebuild without the tool figuring that I would just use the original shim measurements and would be fine ... Until I discovered that whoever else repaired/ rebuilt the left side did not do it correctly .. I fumbled around and got it together and all was fine for a few months until the axle seal failed and I was leaving a trail of 90 weight where ever I went. So I bit the bullet and bought tools needed to do the job from scratch . After re doing the job I discovered that even the side that was not leaking was off on the axle height as well .

 

[Output Shaft]

Sorry for the multiple posts... but you mentioned that you already replaced the old shims on the driver's side with new shims.

They too have to be replaced in such a way that they center the knuckle.

Unless the new shim/s thickness was measured with a micrometer and compared to the old, and matched proportionally to the old ones.... Unfortunately... The driver's side knuckle is now out of alignment. ...Ouch!

 

[leucadiacruiser]

Ha @Output Shaft I obviously should have read one thousand and ONE posts Looks like another week on jack stands but all for the cause. Appreciate the input.

 

[rustybucket]

What are the symptoms that a knuckle needs a rebuild? Never done one before but I have done tons of other automotive work in the past. I am looking at another vehicle and park my truck until I decide what to do with it "frame is rotting out"

 

[Randy88FJ62]

Rustybucket,
A knuckle rebuild is usually required when the axle seal fails and diff oil gets into the knuckles. The diff oil then mixes with the grease and makes is slushy and leaks out the knuckle wiper on the inside of the tire.

Another reason is if the knuckle grease is low causing the top and bottom knuckle bearings to fail (trunnion bearings). Failure of these bearings can cause steering and front end suspension play.

 

[leucadiacruiser]

@rustybucket pull up a chair, some coffee and search 'birf soup' and enjoy the show In my case, it was just age more than catastrophic failure. From what I've read, knuckle seals/bearings seem to be good for 30,000 - of course that depends on how hard and where you drive your rig. A million and one great threads on the subject that can get you through if you have time and patience.

 

[augirthedude]

@rustybucket pull up a chair, some coffee and search 'birf soup' and enjoy the show In my case, it was just age more than catastrophic failure. From what I've read, knuckle seals/bearings seem to be good for 30,000 - of course that depends on how hard and where you drive your rig. A million and one great threads on the subject that can get you through if you have time and patience.

Better be longer than 30 K miles . Check for play when rotating tires . Service as needed.

 

[pandasfj]

Do they still sell that sst or is there another style tool to do the same job? I'm looking to do this knuckle job some time next month. I was reading that you can use the same shims as long as you put them back in the same spot as Output had mentioned. Being a noob to all this I'm starting to read up on this and hoping the same shims will be ok to reuse. Just collected all the right parts and materials to get the job started. I'm looking into what brand of grease to use and how much to buy. Hope you get it all squared out.

 

[leucadiacruiser]

Thanks @pandasfj For the SST most likely someone in your neck of the woods will have one you can borrow if you don't want to buy it outright. Pretty sure its still available for purchase or numerous threads on making your own, too. This is one of the threads I used repeatedly - includes tool list, quantity and type of grease, and number of paper towel rolls!

 

[rustybucket]

yea, well the truck is pretty warn but still drives. I am looking for extra work "this month has sucked" for income. I will need to also have timing. Being that, shop space for a month, and find a frame or just bag the truck and find a doner.