knuckle shims problem (1 Viewer)

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red66toy

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Hi,
I am about to do a disc brake conversion on my 65 FJ40 using some FJ60 knucles parts but I have a slight problem. The guy that I got the 60 parts from didn't keep the knuckle shims in order of where the came from(they were scattered all over the box :mad: ). I know that all I have to do is to add the right amout of shims to get the preload correct but since I don't know the factory setup now(what shims go where), am I going to need that super expensive SST to get the knuckles aligned right? Thanks.
 
Yeah in theory you will; in practice you dont. I would get new shims or clean the crap out of the old ones then try to put an equal amount top and bottom. Check pre load then start removing shims equally top and bottom till you get to the correct pre load. This will get you close enough. WHat you dont want is a bunch of shims on one side or the other.
 
red66toy said: I know that all I have to do is to add the right amout of shims to get the preload correct but since I don't know the factory setup now(what shims go where), am I going to need that super expensive SST to get the knuckles aligned right? Thanks.

Yes. But there are some who have made a less expensive, equally effective tool for this purpose too. There's a Toyota Trails write up for the DIY tool, but I have no link.

Even if the person who sold you the knuckles had kept the shims together and segregated, you would still have to do the SST alignment (or else replace your axle seal every 6 months). The reason is because the shims were sized for the unique combination of those specific knuckles and the specific axle housings they came off of. New axle housings = new shims for the knuckles.

This job is worth doing right.

Edit: Changed "New axle shafts = new shims for the knuckles" to "New axle housings = new shims for the knuckles" -- thanks Mace
 
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Cool, thanks for the help guys. :D
 
as a starting point you should have 2 very thin , 2 thick ( maybe 4 ) , and 2 somewhat thick.

the somewhat thick or thick ( if 4 same ) go 1 each under bottom cap.
then put 1 thick and 1 thin on each steer arm and tighten. flop knuckle back and forth by hand , it should be just stiff , not ratchety or flip floppy loose but stiff like there was really thick peanut butter(cold)in there.
 
If you want to be more scientific about it than cold peanut butter, the FSM calls for a 4-5 lbs. pull on the steering arm.
 
peesalot said:
as a starting point you should have 2 very thin , 2 thick ( maybe 4 ) , and 2 somewhat thick.

the somewhat thick or thick ( if 4 same ) go 1 each under bottom cap.
then put 1 thick and 1 thin on each steer arm and tighten. flop knuckle back and forth by hand , it should be just stiff , not ratchety or flip floppy loose but stiff like there was really thick peanut butter(cold)in there.

Thanks, that gives me a good starting point to tackle this. I do have a FSM so I am going to adjust it to the correct preload.
 
If you are going to be running bigger tires you are going to want to preload your knuckles more. I rebuilt my front axle not long ago and recently I was getting some death wobble. This past weekend I tore my front axle down because my front locker is jacked, but I re-preloaded everything when I reassembled. I'm running 18-20lbs on marlin arms and death wobble is now gone.
 
Thanks for the tip, I am currently running 32s though but I might be going to up to 33s on a 16" wheel.
 
Chase, there are several guys on this board and Pirate who will loan you the SST. Send them a deposit equal to the cost of it and pay the postage. Chef and TornadoAlleyCruiser share one that I have borrowed. You might contact them and see about availability. Have you figured out the inner seal to replace the bronze bushing? I don't remember the part #, but it is posted here, maybe in Tech.

GL

Hope that adapter works for you.


Ed
 
FLFJ40 said:
If you want to be more scientific about it than cold peanut butter, the FSM calls for a 4-5 lbs. pull on the steering arm.

Good call on that one, but remember that you check that BEFORE putting on the wiper seals. You know the rubber/felt apparatus on the inboard side of the knuckle. Just by themselves they will add a lot of resistance, making you think you have it right.

You can get the preload set using the hit-and-miss/ trial and error technique, but the SST will allow you to center the axle in the seal, leading to longer inner seal life.


GL

Ed
 
Oh I forgot to mention that when I took my axle apart I had 8 lbs of preload and still had a wobble, but I'm running F-ed up 35 swampers
 
Degnol said:
Chase, there are several guys on this board and Pirate who will loan you the SST. Send them a deposit equal to the cost of it and pay the postage. Chef and TornadoAlleyCruiser share one that I have borrowed. You might contact them and see about availability. Have you figured out the inner seal to replace the bronze bushing? I don't remember the part #, but it is posted here, maybe in Tech.

GL

Hope that adapter works for you.


Ed
Ed,
Thanks, I am actually using a axle off of a 69 FJ40 for the conversion. Someone has offered me the tool to borrow so hopefully that works out. I got the adapter today, it looks awsome. You did a great job.
 
Quick question, am I also going to need a digital measuring caliper to use with the SST?
 
What exactly is the SST and how does it work? I am in the middle of rebuild my knuckles for my 60 and was curios if I really need this. I replaced the old shims with new one in the exact order they came off. Is this ok or should I still try to find and SST. If so anyone around the Minneapolis area have one I could rent.

Thanks Patrick
 
Mr. Toad said:
New axle shafts = new shims for the knuckles.


No, the statement is new steering arms/knuckle bearings = new shims.

Axle shafts are centered no matter what. I can change as many shafts as I want as long as the steering arms/knuckles/trunion bearings remain the same.
 
bustanutley said:
Oh I forgot to mention that when I took my axle apart I had 8 lbs of preload and still had a wobble, but I'm running F-ed up 35 swampers
check your tie rod ends and your spring bushings..
 
I think SST stands for Special Service Tool, or Shim Setting Tool, or Super Secret Tool or something like that. It is a device that allows you to put the knuckle back on the housing with the axle shaft EXACTLY in the middle of the knuckle. If the axle shaft would be off center, it could tear up axle seals quickly. It's kind of expensive (like $150) to only use it once in a great while. Try to borrow or rent one for the occasional use. I have one I could loan you if you need it. Luke
 
Mace

Originally Posted by Mr. Toad
New axle shafts = new shims for the knuckles.

No, the statement is new steering arms/knuckle bearings = new shims.

Axle shafts are centered no matter what. I can change as many shafts as I want as long as the steering arms/knuckles/trunion bearings remain the same.

D'oh! I should have said "axle housings", as I stated in the sentence before the one you quoted. I would never skip the SST (or its equivalent) setting-up knuckles on any axle housing other than the one that the knuckles came off of.
 
Mace said:
check your tie rod ends and your spring bushings..

TRE are brand new fj80, driverside shackle bolts keep loosening themselves, bushings them self are good.

My wobble was a comble of knuckle preload, loose shackle and very unbalanced tires.

No wobble since last weekend. :)
 

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