Conflicting information for balljoint torque spec

Hi all, I was going to piggyback off of a prior post but felt that this deserved it's own thread since the information on here seemed to be critical to safety.

Can someone clarify the torque spec for the 4 bolts that hold the ball joint assembly to the knuckle for a 03' Tacoma? I read that it is 59fl/lbs but it will overstretch the bolts and cause them to be weak possibly leading to failure. From what I gather, Tacomas 01' and later came with the protective boot cover over the BJ. Around that time was when they switched the bolts to a bolt and washer design as opposed to the flanged bolt design of the earlier years. With this switch, the bolt was only supposed to be torqued to 37ft/lbs. The part number for the 01' and later Tacomas is 90119-10933 for the 4 bolts.

Per this article, it states that this part number would start stretching at 44ft/lbs and be severely stretched at 51ft/lbs. 59ft/lbs seems like it would be well into the danger zone.

https://www.mighty90s.com/forums/di...j-bolts-and-why-its-important-prado-90-series


Where I found the 37ft/lb spec was from Timmy the Toolman's youtube video linked here. Read the description of the video.

"The #90080-10066 bolts that are paired with the lower balljoints with no dust cover should be torqued to 59 ft-lbs.
*The #90119-10933 bolts that are paired with the balljoints with a dust cover have a lower tensile strength and should only be torqued to 37 ft-lbs.
*This is why people have reported seeing two different torque values in the Toyota factory service manuals. Torquing the #90119-10933 bolts to 59 ft-lbs causes stretching of the bolt and will increase the risk of failure."

https://www.youtube.com/watch?v=bfLvtEnX9qk

I could only find 59ft/lbs referenced on about half a dozen guides that I find here but it seems like there may be more to the story?

 

I replaced the lbj's on both my 04 tacomas and 2 of my 3rd gen 4runners a few years back, I just did the wifes 02 4runner last week. I replaced the mounting bolts on all trucks and torqued them to 59lbs.

 

I wonder if its a 4runner thing.

Here's the page from an 03 Taco FSM that shows 59.

 

I've always torqued the new mounting bolts to 59ft lbs on my Tacomas & 4runners. 1 4runner and 1 Tacoma are both lifted, it's been a few years with many Offroad adventures and never a issue.

 

I thought that might be the case too but the bolt's strength shouldn't be affected by the vehicle. The first link actually tests the four different bolts off of the vehicle and found that the one for the tacoma starts stretching quickly.

 

@Timmah! might be around at some point, maybe he can shed some light.

 

I don’t think my personal spin on it matters, but since I used blue locktite and *maybe* it’s considered a lubricant when still wet, I torqued them to 58ft lbs. I’ve read that things like anti seize, etc can throw off the accuracy of a torque wrench. With that in mind I reduced it a whole one foot pound. Haha, seems totally fine, and plenty tight without being ridiculous.

 

I always apply blue loctite to the new bolts then torque to 59.

 

This is from the 2003 Tacoma FSM. Shows 59ft/lbs.

 

It’s also entirely possible the failures were from over torqued bolts, either due to human error using the torque wrench during initial install or a faulty wrench that’s inaccurate. A faulty bolt may also be a possibility..?

I mean, do you want to live forever anyways? At some point one must stop with all the fretting and just send it.

 

I remember that there is some type of reference chart for bolts and the maximum torque specs so I tried by best at googling and this is what I found below. I believe the bolts for the later Tacomas are 90119-10933 and I believe someone here mentioned that it is NOT a class 10.9 and that he had a bunch sheer off when trying to torque it to 59ft/lbs. If it is not a class 10.9 bolt then the next step down is class 8.8. According to the test that I linked in my first post, they found that the bolt starts stretching at 44ft/lbs(60nm). Per the charts here, the maximum torque for a class 8.8 M10X1.25 bolt is roughly 36ft/lb - 38ft/lb so it makes sense that at 44ft/lb the bolts starts to stretch.

https://www.trfastenings.com/Produc...ad-and-Tightening-Torques-Fine-Metric-Threads

https://www.fastenermart.com/files/metric_tighten_torques.pdf

Regardless, even if it was a class 10.9 bolt, per the chart 59ft/lb is still well over the maximum of 53ft/lb.

 

Never heard anything other than 59 ft lbs.

Might wanna look at other sources for torques. I've seen 65ft lbs for M10 10.9's for some of those generic torque settings.

Better yet, consult the factory, which is 59. If this were an issue, they would have had their asses handed to them 2 decades ago in lawsuits.

 

That's more than likely for a coarse thread bolt. The M10 X 1.25 is a fine thread which is actually kind of uncommon from what I can find. More application appears to use the 1.50 thread pitch which increases the amount of torque that can be applied.

It wouldn't be the first time that I have seen FSM with incorrect information but I do get what you mean. It just seems that everywhere else I look seems to suggest different than the FSM so I just wanted to pick the minds of TW.

 

Finger tight one turn with the wrench and never seize if I want to remove them without the torch

 

@drr @Speedytech7

It seems logical that the torque spec could be different between a flanged head bolt and the OEM bolt type with the washer design that originally came with the '01-'04 assemblies. FWIW, I have switched to the flanged type (acquired from McMaster-Carr) and torque them to the FSM recommended 59 ft/lbs spec.

 

If this topic comes up again I'm going to start welding ball joints onto the spindle. But yeah I just do em to 60ft and call it a day, it works fine for both bolt anecdotally.

 

I've always done 60ft/lb on them, because odd numbers like 59 don't settle well with my mild OCD I guess.

 

Did you reuse the rubber cover for the balljoint with those flanged bolts?

 

As far as I could tell, thread engagement was fine and not an issue. But it did not seem appropriate to continue to run that rubber shield because the wide flange grabs the shield and causes it to twist when torque is applied.

 

Yes. It is also unclear what the grade is of the OEM bolts, I have a hard time imagining that they’d use a grade 8.8 in such a critical component but there are no definitive markings showing that they’re 10.9. I’ve been using the flanged head grade 10.9 bolts from McMaster-Carr for many years with no issues at all.

Many of the issues seen with the LBJ bolts shearing are due to under-torquing, not over-torquing. They will start to back out from vibration and then relative motion will cause fatigue and shearing. Blue Loctite and 59/60 ft-lbs will solve that issue.