U-bolts bending under load?

Def. see it now but still think it's just made that way. This wasn't a Ferrari.

 

yikes, this makes me want to go out and look at mine...haven't given that area any real thought before. But if that were to fail on you while on the trail or on the highway you're gonna have a real bad day.

 

I doubt it. I remember seeing 90 pounds once and thinking 'Ha'. 3X that maybe.

 

Damn that sucks

 

Ok I went out and cleaned up the area, seems those cracks are simply the paint. Underneath there is a little surface rust but they seem structurally sound.

I personally have never overtorqued these, unless my wrench is off. But the wrench seems spot on for things like lug nuts at 83 ft/lbs so I don't see how it would be off at 90.

It's just strange that this is happening and I don't see much info about it happening to others, which is rare with these trucks since everyone and their mother has one. You'd think it would have come up by now.

 

Ur in Oakland, I have a pair for you if you want em

 

Ya, something is not right...those shouldn't be spread like that.
IMO, Jeff

 

60 FB on a 14mm.

 

Use your words. What are you trying to say here? You think the correct torque is 60 ft/lbs on these 9/16" (14mm) u-bolts?

The range I've seen from Google results is 65-95 ft/lbs for 9/16" u-bolts, but most say 90. Toyota service manual definitely says 90 ft/lbs for 4x4 1st gen Tacoma. So I gotta disagree with what I can only infer you are trying to tell me.

 

SOLVED: https://www.tacomaworld.com/threads/new-u-bolts-bending-while-tightening.557643/

Time for new saddles. And u-bolts. Feck.

 

I found the problem. You are running lift blocks below.the leaf packs. Remove the blocks, install the necessary leafs to properly raise the truck, toss your current u bolts, get new ones and tighten to your content to get the right cut size on them, then remove the u bolts and cut them all to necessary size. Problem solved.

 

That's the overload leaf. There are no lift blocks. I don't see how that would have anything to do with it anyhow.

 

Jesus. You are right. I'm sorry. I must be more tired than I think from work. Don't mind me.

 

I was just throwing it out there. Perhaps just cheap Chinese crap or they were made on a late Friday afternoon before a holiday. I sure as hell are gonna be watching mine after seeing this. Thanks and good luck

 

The 90 ft/lbs torque is based on dry threads. Oil or anti-seize lowers the torque a lot to get the same tension on the bolt. I find WD40 is good for mild corrosion resistance and eases disassembly. But WD40 lubricates so little that is does not effect bolt torque much.

 

Where did you find this info?
You’re saying the entire Toyota service manual torque specs assume no lube? Or just this one torque spec in particular?

It's odd to me that they would specifically spec u-bolt torque as dry, since those are some of the most infamously difficult hardware to remove. Almost everywhere you find instructions for installing u-bolts they suggest anti-seize lubrication.

*Other folks, how do you torque your u-bolts? Dry or lubricated, and how many ft/lbs? If no one else lubes and torques to 90 ft/lbs then I guess it's my mistake.

 

I have found bolt torque specs at various technical web sites.
Notice the difference between dry and lubricated torque.
https://www.fastenal.com/en/83/torque-calculator
Down in the corner the notes about K value is helpful
https://www.fastenal.com/content/me...nt-library/Torque-Tension Reference Guide.pdf

 

What I’m gathering from your info is that 90 ft/lbs is optimal for my bolts, but even though my wrench was set to 90, I exceeded that amount by using anti seize. It looks like I should torque to 17% less than spec when using anti seize? Is that what that K value is telling me?

 

I just run them up snug and call them good.

About the only time I hunt for the torque wrench is engine work and fly wheel bolts.

You did clean all the mud off it would only take a little to throw things off.

Living in the Northeast USA I only tried unbolting u-bolts one time now they just get cut

 

Depends on the metal hardness. Low end 60 high end 158 metric bolts, 9/16 US bolt is a different rating. Bottom line is what does Toyota say? Something bent the bolt and the plate.