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travelin texans
02-25-2020, 10:07 AM
I posted that's not necessary to torque your RV lug nuts EVERY trip. Torque initially, drive couple hundred miles, torque again & done til wheels removed again.
Constant torque will eventually break studs &/or crush the lug hole on the wheel, especially aluminum wheels.
This brought a rather lengthy rebuttal on another thread.
What say others?
I've been doing the above torque procedure for 40+ years in all RVs without issue & never lost a wheel.
If torque is checked every trip on your rv do you also do so on the truck every trip? If not why? Same type wheels!

CWtheMan
02-25-2020, 10:59 AM
Keystone owner manual starting on page #24.

https://www.keystonerv.com/media/9141971/keystone-owners-manual-2019.pdf

JRTJH
02-25-2020, 11:03 AM
I'm no mechanical engineer, so this is my "take on torque" rather than an "expert take on torque"...

The reason for sequential torque on wheels with countersunk lug holes is to assure the wheel is centered on the hub/lugs as it is tightened/torqued to specification. RV hubs are "lug centric" and not "hub centric" which is different from most automotive hubs. If you were to loosen ALL of the lug nuts at the same time, the wheel would "lose center" and might not "recenter" without the sequential torque process.

So, when a wheel is removed, it is first sequentially torqued to a low value, then sequentially torqued to a greater value and finally sequentially torqued to the final value. This assures the wheel is centered, evenly torqued and all the lugs are at the "final tightness".

When retorquing, it's always been my understanding that the "variability of wrenches" (+/- tolerance) mandates that each lug be "slightly loosened" (one at a time) and then retorqued to the final value. The reason the "sequential step process" is not required on retorquing is because the lugs are loosened "one at a time" and the wheel does not "lose center position" with the remaining lugs holding it in place.

It's my understanding that if the lugs are not loosened before retorquing, the process can (not will) cause lug stem stretch/thread distortion which can damage the lug stem and possibly, over time, lead to fatigue that can cause lug stem failure. So, I was "taught by master aircraft mechanics" who were "taught by aeronautical engineers" to always loosen a bolt/nut/screw/lug before retorquing. Whether it's a requirement or just a "best practice' or even an "old mechanic's tale" (similar to an old wive's tale) is something I can't vouch for....

I always loosen each lug as I retorque, because that's the way I was trained to do it on equipment that costs "millions of times more" than my trailer.

"Right way" or "wrong way" that's "my way".....

gearhead
02-25-2020, 11:58 AM
hmmm....I've never been exposed to the loosen and re-torque theory. Just for general purpose rotating equipment we would go 50%, 75%, and then 100%. Was that actually practiced? Probably not. But there are some general rules for best practices...no Never Seize on the threads, no length-wise extensions on the torque wrench, at most a drop or 2 of light oil on the threads. We have used Hi-Torq hydraulic torque wrenches and some machines, mostly large steam turbines, required flame heating and stretch measuring.
For what we are talking about here, I would stick to the torque it 3 times and occasionally check. But be careful about when you check you are not taking it over the spec. It's easy to do with a "click type" torque wrench. A beam type may be better in this case.
https://www.boltscience.com/pages/tighten.htm

travelin texans
02-25-2020, 02:03 PM
I was also taught the "loosen one at a time then retorque" process along with the sequential tightening.
Also in the "right or wrong, but my way" category & to old & set in my ways to change now, it's worked well this long.

notanlines
02-25-2020, 03:49 PM
I’m with Danny on this. After I’ve checked a couple times, never again until new tires. And simply never on the truck.

66joej
02-25-2020, 03:56 PM
I’m with Danny on this. After I’ve checked a couple times, never again until new tires. And simply never on the truck.

^ ditti on this. Only time I check TV lug nuts is when I get a service with tire rotation. In this case I loosen and retorque the nuts. Seems the youngster that does the rotation uses a 250# torque release extension on his impact!:banghead:

Roscommon48
02-25-2020, 04:34 PM
just check on occassion. 110 pounds. life goes on.

KRumm
02-25-2020, 07:33 PM
My better half days it's best to be torqued regularly...

tech740
02-25-2020, 08:00 PM
I may be wrong but I thought that I read someplace you check trailer tires more because if they are exposed to tight turning there is a lot of “scrubbing”. This can cause force in different directions then just rotational. Could be way off I just thought that I read it someplace.

sourdough
02-25-2020, 08:26 PM
This thread is interesting :) but just wanted to throw something out I've experienced as we talk about truck tires.

Had a near new Ram 1500 and started towing the current trailer, about 9300 lbs. Checked torque at the start of a trip and mid trip (multi days). Trailer stayed snug generally, the truck lugs would loosen every time I checked them. I was really surprised but it just kept up. Don't know if it was "that" truck, the 20" factory wheels or what. Had the same 20" wheels on my 3/4 and the 1 ton. Haven't towed with the 1 ton but the 3/4 had no problem. Just throwing that out there as a possible anomaly you might encounter.

Dave W
02-26-2020, 04:22 AM
Loosen/retorque is just like pulling a wheel. You are starting all over again.

You stretch the lug (not the nut) the first torquing (90-110lb ft for 1/2-20 nuts), it will relax a bit and you will lose a little of the clamping force from heat (brakes/ambient) and vibration(road/balance). Reset the FULL clamping force by doing the second torquing without loosening.

Torque one time, drive then retorque after the first trip.

I have seen that loosen/retorque advice for years - it's usually incorrect advice

flybouy
02-26-2020, 07:49 AM
Lot's of different thoughts and opinions on this subject. With the proliferation of disk brakes and alloy wheels years ago the torquing of wheel lugs came into focus. The more dramatic heat swings of the disk brakes and wheels that expand/contract more readily brought the subject to light.

I have followed the wheel mfgs recommendations of torque with star star pattern to first snug the nut, then torque to spec. Drive 50 miles, retorque. I will check the torque after a long period of braking where I suspect high temps have been created i.e. stop & go traffic for extended periods, mountain driving, etc. or after an "extreme" temp change such as driving from a 80 deg ambient to an area of 30 or 20 deg. This more habit from the days of having aluminum wheels on cars. Today's alloy wheels are much less susceptible to this as they are better at holding air pressure than the old aluminum wheels were.

As for retorquing I've never "backed off" a nut then tightened it other than a castle nut on a spindle to seat a set of cone roller bearings. A "click type" torque wrench in my mind should release or "click" or "beep" if digital at the preset value. That's what's worked for me for the 50+ years YMMV.

gearhead
02-26-2020, 10:42 AM
I probably should clarify my comment about click type torque wrenches. My concern is a good sized fella at a tire shop putting all his weight with a lot of momentum on the wrench and flying way past the click. Going at it slow and careful is no issue.

Tbos
02-27-2020, 05:01 PM
On my 2 previous TTs the wheels were painted and it took several trips before the lugs didn’t need to be torqued each trip. It took that long before the paint on the mating surfaces was gone. Had to change a tire and beige I mounted that spare I took sandpaper to the mating surfaces. That made a huge difference. On the 5th wheel the alloy wheels never need to be torqued. I will check them occasionally using the click type torque wrench set to 105 rather than 110.

bobbecky
02-27-2020, 05:22 PM
If the studs and lug nuts are rated for the 120 ft lbs of torque, and you never check the torque or retorque the lug nuts at anything over 120 ft lbs, I find it very difficult to see how you would stretch the studs. The assembly is designed to handle the stresses of side loading and all the other stresses while rolling down all the fine roads we travel on. The manufacturer says it’s necessary to check the torque occasionally, which I do, maybe not before every trip, and once in a while one or two of the lug nuts will maybe turn a little bit, while all the rest of them don’t move, so there is no additional torque added to the nut and stud assemblies. I’d much rather check the torque every so often than be concerned with a wheel coming loose. There will be much more stress and be more likely to break a stud if the wheel gets loose instead of being firmly attached to the hub.

ReNeu
02-28-2020, 12:39 PM
When I started driving we would change a tire wheel and tighten it up snug then giver a bit. Went by feel. Never lost a wheel or had one come loose on vehicle or trailer. Then one day it seemed the tire shops were using torque wrenches. Probably thanks to China for making them affordable and plentiful. If thinking about it has most to do with so many vehicles had alloy wheels. I do now use a torque wrench when doing my wheels and like that I know they are the same but more important is that I don't have them over tight which with alloy which to me would be a worse situation.

flybouy
02-28-2020, 01:29 PM
When I started driving we would change a tire wheel and tighten it up snug then giver a bit. Went by feel. Never lost a wheel or had one come loose on vehicle or trailer. Then one day it seemed the tire shops were using torque wrenches. Probably thanks to China for making them affordable and plentiful. If thinking about it has most to do with so many vehicles had alloy wheels. I do now use a torque wrench when doing my wheels and like that I know they are the same but more important is that I don't have them over tight which with alloy which to me would be a worse situation.

I think another factor which I haven't seen mentioned is the proliferant use of "floating disk rotors". Most vehicles today use a disk brake rotor that slides over the studs and gets tightened to the hub via the wheel lugs. If the nuts aren't tourged evenly and in a pattern then you risk warping the disk.

LarrySharon
03-05-2020, 08:15 AM
I don't check every time but a lot. I have sometimes had a loosen nut. (not me) lol. But I don't mind rechecking it doesn't cost me anything and it does not take long. Plus I feel like I did something safe. :)