Wheel bolt tightening

[v6camrydriver]

Recently removed the front tyres and when putting them back on forgot to tighten them up in the proper sequence. I just went round each bolt with the torque wrench in a clockwise direction from the top. Does this matter?

[Mike Gerber]

It probably won't hurt anything, especially if you used a torque wrench. It is best in the future to tighten in an alternating pattern to insure even tightening. If you really feel anal about this mistake, you can loosen the lugnuts on each wheel and retighten them in an alternating pattern, using the torque wrench. You don't have to remove each wheel to do this, only loosen and retighten the lugnuts.

Mike

[capedcadaver]

of course don't use the tq wrench to re-loosen them... precision instrument, not meant for heavy loosening. i always do mine (on any 5 lug car) in a star pattern using a tq wrench.

[5SlowFE]

^

What he said, especially about the torque wrench. Most people seem to think that torque wrench = breaker bar. NOT true!

[TheKevin]

agreed, use the star pattern.

tighten the lug nuts with a torque qrench @ 76 ft lbs.

[lenjack]

Suggest you do it in steps, using the star pattern. 40, then 60, then 76.

[djb2]

It's not ideal, but it's not necessarily a problem.

The reason for criss-cross tightening is to assure centering and even clamping.

Most modern car wheels are almost always hub centric -- the center of the wheel fits tightly around a small lip on the wheel hub. Older cars sometimes used only the hemispherical or conical shape of the wheel bolts or nuts to set the wheel position.

Once tightened, the wheel-to-hub clamping friction provides the support, not the lip or shear strength of the fastener. If you tighten in order around the perimeter, the wheel could bind off-center. Later it could shift to be centered, leaving all of the wheel nuts loose. Hub-centric wheels don't entirely prevent this from happening, but do make it much less likely.

The Toyota steel wheels use conical shoulder nuts, but the alloy wheels use flat surface nuts with washers. The flat clamping surface provides no centering, but also doesn't depend on exact centering for correction lug tension. The flat surface reduces the wear on the soft alloy from repeated tightening, and the stress and potential cracking from thermal cycling a work-hardened alloy surface.

The other problem is that you may leave a fastener loose. The first nut has to lever the wheel into position and thus requires more torque for the same fastener spring tension. The second fastener also does a little work. By the time you get to the fifth nut, the first may have lost some spring tension and clamping force.

My guess: anyone careful enough to use a torque wrench probably wasn't inattentive enough for either centering or a loose first nut to be a problem.

[v6camrydriver]

Thanks heaps for all the replies...after realising my mistake I lossesned and re-tightened the nuts in the correct sequence using a torque wrench.

[frojoe]

On a related note, not having a torque wrench I just use the one that is for changing the spare, hand tighten and then step on it a bit. I do use the right pattern. Is there any problem overtightening the bolts. I will assume I'm putting about 120 ft/pounds on them considering my weight and the length of the bar.

[200kmarcy]

Too much torque could strip the hub posts when you try to take the lug nuts off. Worst case the post will break. For most Toyotas it's 76ft/lbs.

[flyeri]

By over tightening you run the chance of stripping the threads out of the lug nut. That is the softer of the two metals. I know people who use 100lbs. I personally use 85-90 on all my vehicles.

[TheKevin]

as i stated before, 76 ft lbs is what's recommended and what i use.

[frojoe]

I won't step on it as hard from now on, or ill step on the bar closer to the nut, try to get down to around a hundred pounds. Thanks guys.

[v6camrydriver]

Buy a torque wrench. It might be an expensive outlay but surely it's worth the peace of mind.

[frojoe]

To be honest, I'm not losing any sleep over an extra 20 ft/lbs on the wheels. I'll buy a torque wrench when I need it for something a little more exact. I doubt sears torqued to exactly 76 ft/lbs when I got my tires changed.