Stripped Knuckle On LBJ Job

[Tyler James Inc]

Got new(ProForged- from what I could find, these are better than MOOG, since MOOG is made in China, and ProForged in Taiwan) lower ball joints, inner tie rods, and outer tie rods for my 4Runner.
I was stoked, as it feels good to know when parts have been replaced. My 'runner has 240k on the clock, and I know no maintenance before 218k.
Anyway, the job was going far too smooth. I had all three joints done(on the driver side) in as much work as I would compare to a brake job. [emoji1360]
I looked up torque specs for the 4 LBJ bolts, and found 59ft lbs. When tightening them, the two outside(covered holes) felt like the threads yielded before reaching torque spec.
Extremely frustrated- and feeling like it's not safe to drive- I was wondering if many have had this happen. An ADD knuckle should be easy to source, but now I'm worried about getting the bolts torqued to spec on the "new" knuckle.
I didn't really find any threads on this when searching, so I'm also wondering why this happened.
Pics for funsies-

Bolts in question-

 

[thegipper]

Double check the torque specs on those four bolts, I'm pretty sure they are supposed to be 37 ft/lbs not 59.

 

[LittleCaesar]

Either the thread pitch was close but wrong or the lock washers helped exceed the torque on the knuckle and the threads gave way.

I would first try and chase the threads with the old bolts or a tap to see if you can get the threads to grab. If the threads are gone I would get a new or used knuckle. If it needs to be driven smooth out the stripped threads and use two larger bolts (3x8, grade 8 or even M10, class 10.9) to pass through the knuckle and get some low profile hex nuts so that they don't rub against the CV. Use loctite. Retapping the threads without the knuckle in a vice would be very hard.

If you are still set on using Pro Forged parts then at least get 8 new LBJ bolts from the dealer.

 

[01thunder]

that cheap shit ain't the same as oe stuff. those bolts aren't the same pitch I bet. use oe bolts on what you can now.

 

[Tyler James Inc]

Double check the torque specs on those four bolts, I'm pretty sure they are supposed to be 37 ft/lbs not 59.

That's really annoying; I think you're right.
I got the info here-
http://www.toyota-4runner.org/3rd-gen-t4rs/103217-lower-ball-joint-removal-installation.html

It seems pretty suspect for those small bolts to be at 59ftlbs, when the TRE nut is only 53ftlbs. [emoji849]

Either the thread pitch was close but wrong or the lock washers helped exceed the torque on the knuckle and the threads gave way.

I would first try and chase the threads with the old bolts or a tap to see if you can get the threads to grab. If the threads are gone I would get a new or used knuckle. If it needs to be driven smooth out the stripped threads and use two larger bolts (3x8, grade 8 or even M10, class 10.9) to pass through the knuckle and get some low profile hex nuts so that they don't rub against the CV. Use loctite. Retapping the threads without the knuckle in a vice would be very hard.

If you are still set on using Pro Forged parts then at least get 8 new LBJ bolts from the dealer.

Thanks for the help. I didn't realize lock washers can effectively increase torque. That's good to know.
I wouldn't say I'm "set" on using ProForged, but I feel kind of stuck with them at this point- one side fully installed, and the other opened and packaging tossed. Has there been bad experiences with PF that you know of?
I think I will get new bolts from the dealer, and try to install them to the proper torque spec. Thanks again.

that cheap shit ain't the same as oe stuff. those bolts aren't the same pitch I bet. use oe bolts on what you can now.

The thread pitch is the same- I did check that prior to installing.
And I know. I am an OEM whore on my VW, and know OEM is always(IMO) best. I don't know why I spaced going to the dealer for these parts. I don't think that would have left me in any different situation I am in now, but I still regret not going OEM.

 

[stir_fry_boy]

LBJ, UBJ, OTE, ITR, LBJ bolt part #'s

Get new bolts, a set of 8 cost me $11. They do stretch a little over time. Best to just replace them.

 

[MandAtaco]

I just ordered 8 of the factory bolts from Camelback Toyota @ 0.91 each, and installed them last night. I'll be honest though, I torqued them to 59ft lbs as I could find the print out from the FSM and thats what the old Chiltens manual speced out. Oh well, I've used that spec before with no issues so I guess it'll be fine. I use blue lock tight on all the bolts also.

 

[TheDurk]

Double check the torque specs on those four bolts, I'm pretty sure they are supposed to be 37 ft/lbs not 59.

Absolutely right!

http://tacoma.site40.net/4Runner_96-02_Repair&Wiring/techinfo.toyota.com/ileaf/02toyrm/02toypdf/02rmsour/2002/024runne/ss/sa/torspe.pdf

 

[A.Wilson013]

The torque spec of the LBJ to knuckle is a debated topic. You'll find people saying 37 or 59 all over the interwebs, but based on the bolt class/size it should NOT be torqued to 37ft lbs- that's for sure.

Pick up any Toyota FSM and look for the "Standard Bolt Torque Specifications" and look up the LBJ bolts... Here's a link for that... http://www.toyotadostlari.com/uploads/03-Service-Specifications.pdf

Class= 11T (As signified by either 4 lines and 2 dots on the bolt head, or 6 lines on the bolt head)
Diamer= 10
Pitch= 1.25

The "Standard Bolt Torque Specification" for such a bolt is 64 ft-lbs. This is NOT 59 ft-lbs, but it's quite a bit closer to 59 than 37...

With that info, I have done 59 ft-lbs, blue loc-tite on all the LBJs I have done (probably around a dozen). I have NEVER seen the knuckle strip, but I did rip a bolt in half once when I tried to torque it to 109ft-lbs. It was a long day.


Here's a picture of the different markings for an 11T Toyota bolt... Thanks Pirate4x4 for the picture and most of this info.

Picture of the FSM page... Thanks again, Pirate.

 

[stir_fry_boy]

22 ft-lb is quite a big gap. I just put new bolts in and hit them with my 1/2 impact. That's good enough

 

[A.Wilson013]

22 ft-lb is quite a big gap. I just put new bolts in and hit them with my 1/2 impact. That's good enough

lol...

 

[AZBub]

I'm actually shocked someone would even post they used Proforged LBJs here. I also wanted to comment that you have the cleanest, and I mean THE cleanest front suspension I have ever seen. It's like it rolled off the assembly line clean. I thought I was being lied to and was looking at a weird angle on a 5th gen.


Sent from my iPad using Tapatalk

 

[JayRolla]

Went does everyone lock tight the lbj bolts?

 

[nobb]

That is a really clean suspension and underbody! With the lack of rust, the only way the bolt would have stripped like that was if someone worked on this part before and overtorqued it. If you didnt already, using a torque gun instead of a breaker bar can often be beneficial in preventing stripped heads on old bolts.

I torqued my bolts to 59 ft-lbs with loctite. 37 ft-lbs is way too low for this grade and size of bolt, it is argued that it could be a misprint in the FSM.

 

[LittleCaesar]

Borrowed from the FJ Cruiser forum:
NUTS & BOLTS: Sizes and wrench equivalents - Toyota FJ Cruiser Forum

It is 59ft/lbs. Blue loctite is used so the bolts won't back themselves out.

My brother has used Pro Forged parts on American cars with success. I can't speak for such use on Toyotas.

 

[LookAtThatDog]

That perfect underbody is seriously Toyota truck porn

 

[Tyler James Inc]

Thanks for all the compliments, guys. I like my shit clean. It's far from perfect, but I try to take care of it!

That is a really clean suspension and underbody! If you didnt already, using a torque gun instead of a breaker bar can often be beneficial in preventing stripped heads on bolts.

It's not the bolt head that's stripped, it's the threads in the knuckle. But I agree; impacts are really awesome for almost any nut/bolt/ situation!
My local dealer doesn't have the bolts in stock, and I really wanna get this fixed tonight. There are a couple reasons I don't wanna replace the knuckle-
1) I'm on the hunt for a manual hub Tacoma swap anyway.
2) Don't wanna replace the UBJ, since I'm getting SPC arms as soon as I can.
I think I'm gonna just re-tap the holes to 3/8", and see if that works out well for me. If that fails, I'll replace the dang knuckle.
I'm really perplexed as to why the threads gave way. I triple checked my wrench settings, and it was 100% positively on 59ftlbs.
They weren't very tight when I pulled them, but they were all evenly tight, and I'm betting they were original.
I really don't see any reason to loc-tite these, so I think I'll pass on that. Like I said, the bolts that I pulled were not loc'd, nor were they very tight, and they held just fine.
Thanks a lot for the help guys.

 

[99Runnr]

In my short time wrenching on 4runners, I've replaced 4 sets of LBJ's. None stripped, I torque to 60 ft lb's with blue loktite as most here have mentioned.

Good luck mending it.

 

[LittleCaesar]

The threads gave way because in the end you applied too much torque thanks to the lock washers, hence if you had used the original bolts you probably been OK.

Also, if you aren't the original owner who knows what punishment the knuckle has received beforehand.

Good luck.

 

[Tyler James Inc]

I wish I could do something to ensure no one ever buys a ProForged product- ever.
I will be returning the stuff I got, and buying OEM everything.
This is absolutely unacceptable. For a company to send a life-dependent product out the door like this is mind blowing.

That being said, I realize some of the blame is on me. I should have known OEM is the ONLY option.
"Enjoy" the pictures-

The bolts were only long enough to grab TWO threads. OEM bolts grab ~5.
Thank God this didn't happen to someone that were less cautious than I- it could absolutely cause a fatal accident.
The good news is- as you can see- the knuckle isn't what stripped. I put the OEM bolts back in, and they torqued to spec without an issue.
Like I said- I'll be pulling the ProForged parts and sending them back ASAP.

I'm not too proud to admit I made a foolish mistake, and I can only hope I can stop someone from buying anything from ProForged.