Knuckle centering...who has actually done it?

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I've rebuilt quiet a few knuckles over the years but never had to do any knuckle replacements until recently. The last four knuckles I've centered using the tool has yielded me 2mm -1.75mm between the two hash marks, and only a total shim thickness of 2mm. Following the manual you subtract 3mm from the hash marks number for the lower shim thickness. So all four I've done have taken the full shim thickness under the steering arm.
How common is this? Anomaly perhaps or is it just coincidence mine have came out like this?

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Pighead

Stop calling it an FJ
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I did that measuring thing, with a borrowed tool, just once. Twice if you count both ends of the same axle, just recently. I forgets the numbers and threw away the paper, but I got shims both upper and lower. you only get shims on top? Does not sound right.
 
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Before you took the axle apart, did you reference and write down factory shim thickness as a reference ? The tool you are using is a great deal , but , when I did a rebuild I was very precise to see the outcome the factory did. Actually , 35 years after a rebuild and I believe the shims determined from Toyota are still great. If you are unsure of history, then I would follow the measurements you are taking.
 
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I just did it on my hj75 which is very similar. Followed the fsm. My guess would be the 40 is the same as 70 series.

With a copy cat tool, which is quite nice really, I get 1.7mm for the lower and .3mm for the upper. Subtracting 3mm from the largest amount of play (the distance between the two lines) in the tool measurement gives you the lower shim measurement. So the larger shim value would be the lower shim, hence folks say 1 thick and 1 thin. The lower shim total shall usually be thicker than the upper.
Unless your 'c' value was quite large.
It was not correct before I did it, so the preload felt a bit loose. Feels much better now with 5mm toe in too.

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I just did it on my hj75 which is very similar. Followed the fsm. My guess would be the 40 is the same as 70 series.

With a copy cat tool, which is quite nice really, I get 1.7mm for the lower and .3mm for the upper. Subtracting 3mm from the largest amount of play (the distance between the two lines) in the tool measurement gives you the lower shim measurement. So the larger shim value would be the lower shim, hence folks say 1 thick and 1 thin. The lower shim total shall usually be thicker than the upper.
Unless your 'c' value was quite large.
It was not correct before I did it, so the preload felt a bit loose. Feels much better now with 5mm toe in too.

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use to have a bj40, sorry for crossing over from the 70's lurk.
 
Joined
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Before you took the axle apart, did you reference and write down factory shim thickness as a reference ? The tool you are using is a great deal , but , when I did a rebuild I was very precise to see the outcome the factory did. Actually , 35 years after a rebuild and I believe the shims determined from Toyota are still great. If you are unsure of history, then I would follow the measurements you are taking.
Perhaps my first post was confusing. These last two axles I did were the results for a knuckle swap or disk knuckle conversion (the first was technically repair from a hack knuckle job someone else did), so since the knuckles aren't original to the axle housing then getting the "original'' shim measurements does not apply.
 
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I just did it on my hj75 which is very similar. Followed the fsm. My guess would be the 40 is the same as 70 series.

With a copy cat tool, which is quite nice really, I get 1.7mm for the lower and .3mm for the upper. Subtracting 3mm from the largest amount of play (the distance between the two lines) in the tool measurement gives you the lower shim measurement. So the larger shim value would be the lower shim, hence folks say 1 thick and 1 thin. The lower shim total shall usually be thicker than the upper.
Unless your 'c' value was quite large.
It was not correct before I did it, so the preload felt a bit loose. Feels much better now with 5mm toe in too.

View attachment 3039528
View attachment 3039529

View attachment 3039530
View attachment 3039538

View attachment 3039539

My C value has been 1.75-2mm as well as the D value. I always measure three times and use the median value although all three are always either identical or close so I'm pretty certain its not a measuring error.
 
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oh, well that is baffling?..some folks reckon you measure from the under side of the lip of the centering tool rather than on top of the the shoulder. This is not how the otramm fella does it on youtubby or the fsm, but it would more than likely give you a larger 'a' value if the tool lip is slightly higher than the shoulder. It may depend on your tool manufacturer possibly. Is it toyota or a copy cat? I imagine there is a few copy cat versions.
Maybe worth investigating as those figures don't match the fsm. If you had a negative shim value after subtracting 3mm, I reckon the fsm would say something in specific. It would feel like a weird assumption that there is only a shim on top.
Maybe even hunt around for another set of knuckles to compare.
 
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Is the spindle attached to the knuckle in that pic? sorry man, just trying to help out
Yes the spindle is attached to the knuckle in my last photo. I'm certain my measurements are correct, I've been meticulous in that aspect. I'm not really sure if the tool is factory toyota or a reproduction. The purpose of this thread was to see if it's an anomaly and to see what numbers others are getting.
 
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There ya go! Man, down here we only count to ten fingers, those fractions do my head in.
May need another tool to calibrate your existing tool. One of the pics definitely shows the lip higher than the shoulder on a copy cat tool. But the height of the tool is crucial. Otramm's tool id dam close to oem.
I got my tool on ebay, it gave results which matched the fsm, so called it good and feels good driving.
 
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My OCD wouldn't let this go so I ordered a factory toyota tool. I'll recheck measurements when it arrives and compare.
Thanks @Racer65 for having these available.
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