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RockRunner
01-27-2011, 07:17 PM
I was putting the calipers on today and found that the knuckles had different bolt sizes. The passenger side needed a M12x30 1.25 pitch, the drivers side needs what looks to me as a M14 size. It looks to me that it needs a M14x30 1.25 pitch.

Does anybody know if this knuckle belonged to an older or newer truck or if it may have been drilled out by somebody?

DaveInDenver
01-27-2011, 07:26 PM
My guess is stripped threads and Heli-coil.

DanS
01-27-2011, 08:59 PM
Tom:

If this was the knuckle I gave you, it came from an '85 4-Runner, if that helps.

It's RH mate matched the 1979 FJ-40 knuckle (and used the same bolts), if that helps at all.

Dan

RockRunner
01-27-2011, 09:12 PM
Thanks guys. No heli-coil maybe it was tapped after it was stripped somehow.

Dan, I used another I got. I think I am going to use yours instead of chasing down different bolts. Who knows they may be metric or SAE with my luck.

So there is no difference between 40's and mini truck knuckles?

DanS
01-27-2011, 11:19 PM
Thanks guys. No heli-coil maybe it was tapped after it was stripped somehow.

Dan, I used another I got. I think I am going to use yours instead of chasing down different bolts. Who knows they may be metric or SAE with my luck.

So there is no difference between 40's and mini truck knuckles?

No difference on ours. One mini knuckle, one 40 knuckle. Not even a difference in marking. I'll snap some pics tomorrow, I've got a mini axle, a 60 axle, and a 40 axle all in the shop to compare...

Definitely metric. The only SAE bolts should be for your seat belts. I buy new caliper bolts if they are anything other than pristine, just because there's only two of them per caliper. Those things are kind of important to me. Plus, they are shiny!

Dan

leiniesred
01-28-2011, 09:00 AM
Weird. I've had at least 4 knuckles apart and probably more like 6. They all had 12mm brake bolts. I think they were all from 1985 mini trucks though.

Air Randy
01-28-2011, 09:20 AM
I think UB said in another thread that anything that is 1979 or newer (40's, 60's, minis) all knuckles are the same.

Pre 79 40 knuckles had the small pattern for the steering arms.

RockRunner
01-28-2011, 09:28 AM
I am going to switch it out later. I don't feel comfortable having to guess what size those holes actually are. Not to mention more spare bolts to carry:(

Dan no worry on the pics. I think I got it figured out.

Thanks guys.

Rzeppa
01-28-2011, 12:59 PM
My 76 FJ 40 were M12 x 1.25 and interchanged with my daughter's 1985 4runner

RockRunner
01-28-2011, 02:25 PM
I wonder if the 60's models had larger bolts:confused: Don't know when they started disc brakes on the 40's. Guess I need to search for a new knuckle :(:(

Time to take some parts apart again and again and again.:rolleyes::(

nakman
01-30-2011, 11:37 PM
I wonder if the 60's models had larger bolts:confused: Don't know when they started disc brakes on the 40's. Guess I need to search for a new knuckle :(:(

Time to take some parts apart again and again and again.:rolleyes::(

Disk brakes would be 1976, iirc. Sounds like someone stripped one, and drilled and tapped it the next size bigger.

DanS
01-30-2011, 11:43 PM
Definitely M12x1.25. I had to chase the threads on the 60 knuckles today.

Also, the same as the 1979 FJ-40, and 85 mini truck stuff. Don't have any small pattern knuckles to compare, but I don't remember them being different...

The 60 and mini knuckles are so similar I couldn't figure out which was which when I took them both apart the same day. The only difference between those and the large pattern 40 is that the large pattern 40 uses cone washers on the bottom studs too, the 60 axles (2x) and mini axle I've got all only have cone washers on the top.

Dan

Rzeppa
01-31-2011, 11:03 AM
Disk brakes were introduced to the USA with the September 1975 build month. A lot of the rest of the world never got front disks on 40 series, and had to wait until the 60 series was introduced in 1980 to get front disks. *J45s and 47 never got disk brakes anywhere, but they did make them 50% wider and can put your nose on the windshield even with a ton of rocks in the back.

J Kimmel
01-31-2011, 11:42 AM
if you already have 14mm bolts, just put it together. I can't remember the last time I took the caliper off on the trail. Buy a couple extra and toss them in your bag, don't sweat it. Find a replacement hub someday and replace it someday when you are doing a bearing packing party or something. Everything will go together fine, you know what you have and what you need, so do it another time. You don't need to get bogged down with more junk to buy and more things to re-build :)

It just adds stress.

RockRunner
01-31-2011, 10:04 PM
I was stress free till we came back to Denver and real life:(. Mini trips are much better, you can daydream about your truck climbing up The Rockpile :D