Re-torquing Trailer Lug Nuts

[khuffmanjr]

Originally Posted by mrjohns2

Funny, there really don't need to be opinions on this. The torque it should be is what the torque spec says. For my 5 lug 14" tires, they are spec'd to be tightened to 95 ft/lbs, then tightened to 115 ft/lbs with an acceptable range of 90-120 ft/lbs.

From the manual: don't tighten lower or higher than the acceptable range.

Yeah, you're right....not really open to interpretation. But to be fair, consider that not everyone has the manual for their trailer, tires and wheels. So some accepted wisdom may be used here. You think a competent trailer service tech has manuals for every wheel he installs? Or better question, do you think he uses them?

If you have the manual/spec for your equipment then that is the best document to follow, for sure.

Ken

[mattchew]

You shouldn't need the manual for your trailer since the manufacturer of the trailer most certainly did NOT make the axles and wheels. Check with the AXLE maker for wheel torque specs. They will be the be all and end all when it comes to knowing how tight to torque the lug nuts.
Easy Peazy. Maybe....

Matt

[CWSWine]

Originally Posted by rkfrazee

Ever since I nearly lost a wheel due to loose lug nuts, I re-torque the nuts on my 24' car hauler at each and every fuel stop. The nuts on the front axle wheels are always tight. However, one or two nuts on the rear axle wheels invariably need to be re-tightened every hundred miles or so. They are still snug, but they are not at the original 80 ft lbs of torque.



Is it normal that the rear axle wheels lug nuts need to be re-torqued more frequently than the front axle wheels? Could I have an alignment issue?

He not talking about RV he talking about a 24' car hauler and when I had my aluminum flat bed it said right on the trailer 80 foot pounds. TT and Fer are normally torque north of 100 foot pounds.

[Tom Sundown]

I don't mean to hijack this thread but looks like the issue is beaten up pretty good. So, which torque wrench do you use?

[TeJay]

This part of a bolts job has not been discussed so far on this thread. Based on my experiences and all that I have read a bolts torque is primarily dependent on its manufactured tensile strength.

A bolt MUST be stretched some but not beyond it's ability to contract to it original length. If it is not stretched enough is will/may come loose. If it is stretched beyond its elastic limit it will not return to its original length and must be replaced.

A properly torqued bolt will provide the necessary or proper clamping force to hold things together. The manufacturer is the one that determines what grade of bolt is used/needed to accomplish the task. The correct torque is applied so it can do its job.

Nobody discussed torque wrenches either. Just because a torque wrench is set to a torque is not an assurance that it is calibrated to that setting. Torque wrenches can be as far as 10% to 20% or even 30% off.

In past threads some have reported that the HF torque wrenches were accurate. That finding surprised me but hey that' OK. The most popular ones click when they reach the set torque. That's very nice because you don't have to look at it to know you are have reached the setting. Provided the TW is accurate.

Most TW are most accurate in the mid ranges and not necessarily at the lower or upper end of their designed range. I NEVER use a FT/LB TW to set a 25 LB torque for say a spark plug.

More proof of the inaccuracy of TW and the technicians who had to use them. Why did the automotive industry switch to "Torque To Yield" bolts on the aluminum engines???

The TTY bolts are used once only then replaced. They actually are designed to stretch in to the yield area of the bolts strength. They are much more accurate and fool proof to install as long as one follows the procedure. That's why they are needed and used on aluminum engines. "Accuracy"

[rkfrazee]

Originally Posted by Tom Sundown

I don't mean to hijack this thread but looks like the issue is beaten up pretty good. So, which torque wrench do you use?

Craftsman Micro-Clicker 1/2" Drive Torque Wrench

[hardy1000]

I just purchased a 8 x 16' double axel Alcome car hauler and factory torque specs are 95 foot pounds.

[CecilD]

I recently did my brakes and torqued my aluminum wheels to 110 ft-lbs. Took a 200 mile trip and just re-torqued them. Each fastener moved by approximately the same amount signifying there was a bedding-in of the wheel. I use a quality torque wrench with good technique.

[RangeMaggotBob]

Originally Posted by Mr_D

Normally, when a lugnut needs retightening like that it means the stud is stretching and needs to be replaced.

Hmmmm...very interesting. Never knew that. Thanks for the info.

[TeJay]

Based on my experiences with bolts and re-torquing once a bolt has exceeded its elastic limit it will never again reach the original designed torque and continue to stretch and then break.

To state that you check the torque of a bolt at say 100 lbs and it needs torquing again to reach the 100 lbs and it DOES again reach the 100 lbs then stops stretching it has never reached its true elastic limit and therefore will not stretch and break.

That's just not how torquing of any bolt is designed to work. The clamping force designed by engineers is just that. They select a grade of bolt that will provide a sufficient clamping for the specific designed task of a machine. That grade has a range of torque. Once it is stretched to it's designed limits it can not nor will not again reach that max torque. That bolt is just scrap metal.

On today's aluminum engines we do have TTY (torque to yield) bolts that will stretch to their elastic limit. WHY?? They will provide a very accurate clamping force. They can only be use once then replaced.

We have had three TT's and they do suggest re-torquing after a few hundred miles and I did notice some lugs did move a bit. Since the TT industry generally selects tires, and rims that just barely meet the weight limits of TT's it is my belief they are covering their butts in case something fails.

There is nothing wrong with double checking ones work by checking torque of lugs. I'll do it but I'm 99% sure my torque wrench is calibrated and in good shape. Almost never has a motor home truck chassis lug nut moved following the initial 150 ft/lbs of torque.