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Dolphinite no longer here

Lug Nut Torque

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Sometimes you have to ask the right question.

Toyota called for 141ft-lb (1988 FSM) and increased it to 170ft-lb (1993 FSM). So my question would be "Why, if 85ft-lbs is enough?". We're all free to try to outsmart Toyota engineers. :)

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Again, I ask, does anyone know what the consequences of too little or too much torque might be? My Dolphin has been on the road with 85# torque since I bought it last year. I'm still alive and there are no problems that I am aware of resulting from this. Both the tire place and my mechanic seem to think 85# is correct (independent of each other and independent of the little metal plaque on the wheel well about the tires, which apparently was intended for the original 5 lug axle, not the updated 6 lug axle which I have.) They must be getting this spec somewhere.

What is going to happen if the dualies aren't torqued correctly? I'm hesitant to more than double the torque without knowing what might happen of they are over-torqued. But I'm concerned about what might happen if they are too loose. Anyone?.

I guess I'm inclined to leave it as is, going with the theory that if it ain't broke, don't fix it.

I guess you could say the same thing about the 5 lug axle with fake duallies. Gee lots of them still out there and didn't break. Why change it.

I don't think I would personally worry if you were at least in the low hundreds but 85 is crazy low. I see some mention of low wheel torque in the front with independent front suspension causing bearing failure and low torque causing excessive bolt heat which makes them fail too. Either way your flying down the highway without a wheel.

Linda S

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Hmm, my Harbor Freight torque wrench tops out at 159 Lbs and I'm betting I'm loosing some force using 2 extensions to get the angle square and safe/correct. Guess I better put an 8" extension on the shopping list. Does anyone use a little "anti-seize" compound at those upper torque ranges mentioned? I can just see myself packing a 4' cheater bar back there with everything else...

TG

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For a cheater bar I use the table pipe from the coach. That'll break anything.

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Does anyone use a little "anti-seize" compound at those upper torque ranges mentioned?

That's a whole different can of worms! :)

https://www.google.ca/search?q=EFFECT+OF+LUBRICATED+THREADS+TORQUE+&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a&channel=sb&gfe_rd=cr&ei=YBUCVJzHH4TM8gfeoYHACw

There's no such thing as a 'little anti-seize', especially when you get some accidentally smeared on your nose! :)

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The lug nuts on my dualies are so tight (at 85lbs as set by my mechanic) I need a cheeter bar on my lug wretch to loosen them. Seems unlikely to me that the nuts are going to vibrate loose and my wheels are going to fall off. So what are the issues involved with torque? What will happen if they are either too loose or too tight? So many different opinions and not much clarity about the risks involved. Whose advise is the safer?

170-180 pound feet dry, and 135 pound feet lubed is the rating for the studs and nuts.

Ford and Chevy use the same size lug-nuts and studs on their 1 ton pickups and also call for 170 lbs. tightening torque. M14 X 1.5. Considering the Toyota only has 6 lugs instead of 8 like the Chevys and Fords - I'll assume the Toyota needs that extra wheel-nut torque even more, not less. Having nuts too loose can wind up with them working loose. Having too tight means that the stud has been stretched beyond it's yield point and it basically weakened and ruined. A metal bolt or stud is basically just a spring. When tightened it is stretched and has tension. If stretched too much (with excessive nut-torque) - it is ruined. Just like a coil spring that you pull too far open. Those wheel studs must be very high tensile alloy to sustain that kind of torque.

A 14 mm grade 9 lug-stud or bolt is made to handle tightening torque like this. If dry with NO lube - up to 180 foot pounds of torque. If lubed with oil, grease, Never-Seez, etc. - tightening torque is 135 foot pounds. And note that "Never Seez" can be many types of lubes. Many variations.

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I have a toyota operators manual that lists 100lbs for dually rear ends

I use a "cheater bar" (piece of pipe about 18" long) on a large 1/2 ratchet to tighten as hard as I can.

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From various sources...and practically, I set my torque wrench at max (150lbs), clicks and I use the breaker bar (or cheater bar) to tight a little more; this makes me comfortable enough for now. Anything below 100ft-lb is way too low in my opinion as a regular small car often calls for 80ft-lb

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Well, I'm about to torque the rear dual wheel nuts.  I was going to ask what torque since the original 85# sticker seems to be for the original factory arrangement.  

I'm going ahead with 150# plus a little dry without lube.

 

 

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I use a 25" breaker bar and tighten till I go "uuugh"...never had a problem with them that way!

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