We're at MOT getting service on our brakes. When the guys went to put the wheels back on the front, they found three bolts that could not be torqued to the 400-foot-pounds they use here. The bolts had to be replaced at considerable effort and cost.
When looking at the bolts with the lug nuts on one can see in the attached photo that two are out further... stripped. As Keith Risch (MOT master tech) explained, the problem occurs when someone puts excessive torque on the nuts. Like with an air driver set too high. Since the bolt is smaller in diameter on the inside where the inner nut holds it in place, this is where the damage occurs. Best to used the air driver to put on the nuts with moderate tightness, then torque them as shown in the pic. So who did this? The front tires were replaced by Herman Power last year about this time.
I will have more to say about service at MOT and Keith in particular. Excellent! That has not been the case with other services we have had here in Nac.
When Herman Power replaced the tires on a rig we had a number of years ago they used only an impact wrench. I asked the tech what he was torquing the bolts and he replied that he just turned up the gun as high as it would go. I didn't know any better at the time. Disappointing that they are still not torqueing properly.
jor
400# lubed may be too high . Look up the nominal spec for the retainer nut size. My bet is 300# max.
Always better to hand tighten for final torque of course.
Something else other than lug nut torquing going on there. The threads that would have been up against the inside of the hub are still good. That stud is pulled into the hub and the serrations lock it if the smaller nut on the inside is tight. Looks like the someone stripped the threads trying to put the stud in.
Right . Almost looks like it was never fully seated.
Thanks for the input. There were six bolts that had to be replaced on the front wheels. So it likely happened as I described... over tightening the lug bolts. I took the bolts to Herman Power and talked to Craig Power. Without hesitation, he said to bring him the bill and they would cover the cost. He also said they try to closely monitor the torque of their impact tools, but sometimes problems occur.
I asked one of the MOT crew about the 400 ft pounds torque that they use and they confirmed that is what should be used.
Be sure to differentiate between 400 lb-ft DRY vs LUBED. Big difference!
And, with Aluminum wheels, they need to be retorqued after a few hundred miles.
They are dry, not lubed.
George
Correct.
But, have seen "Bubbas" slap grease on them then use an impact.
I know, you have met Bubba!
And to this topic, I have never had a shop use a torque wrench. I doubt many of them even own one that is properly calibrated. So what must one do.
What I get is we "set" our impact wrenches. Hummm.
When you over torque a stud or bolt it will stretch. This is called necking as the stretched part is narrower and the thread pitch changes. Running the nut onto the stud will show if this is the case as it will jam. Often it's running the nut on a stretched bolt that causes it to strip. It's OK to use an impact for running the nut up or off. It's not OK for final tightening. When I had my front tires replaced they used a torque wrench both on installation and when rechecking the torque 100 miles later.
In my past life with large fleets we always used a torque wrench on critical items like wheels. The wrenches were regularly checked against a reference unit.
Here is Alcoa's wheel service manual with everything you need to know.
https://www.arconic.com/alcoawheels/catalog/pdf/servicemanual-english.pdf
Keith
Socket, 3/4" breaker bar, regular 1/2" torque wrench and 5' thick wall iron pipe with 1/2" socket welded into one end: Torque Wrench extensions (http://www.specialpatrolgroup.co.uk/spooky/torque/torque.html)
You will need some kind of stand and extension to get in far enough to reach the nuts on the rear wheels.
With this, even a 100 pound weakling can properly torque the lug nuts. No expensive tools needed.
Used this for the last two decades with a "custom upgrade"/elegant one made by a fellow Foretravel owner that even has a set screw for holding the handle of the breaker bar in the pipe.
On mine, 400 lb-ft requires a torque wrench setting of 94 lb-ft-- this is dependent of the length of the pipe with longer pipe requiring less input torque.
Lubed is much better and fights corrosion .
But, one would have to KNOW how much to lower torque specs when going from factory recommended "dry" to "lubed".
Said another way, lubing and using dry torque specs will over-stretch the bolt!
If you ever want to get rid of it, I know a coach that would love to have it back! :))
Hummm..... I was at Hermann power tire yesterday dealing with a defective tire. My next stop was at the mothership to get a replacement lug bolt that was found damaged when I replaced the defective tire last week. Herman power put the tires on 1.5 years ago.... does anyone see a trend here...
Alcoa gives lubed value. About 100# less . or 300+-25.
My files show that 12 of them were replaced the last time fresh Michelins were done in 2014.
That's why I never let a tire shop air gun our wheels. If you use a little Anti-Sieze Amazon.com: never sieze (https://www.amazon.com/s?k=never+sieze&hvadid=241924514100&hvdev=c&hvlocphy=9032587&hvnetw=g&hvpos=1t1&hvqmt=e&hvrand=483932441878313225&hvtargid=kwd-4453486723&tag=googhydr-20&ref=pd_sl_5e971df42s_e) on the threads, you can torque to 20 percent less and sure the nuts will come off easily.
Our forum is full of shop mistake posts. A big reason to do as much as you can yourself.
Pierce
We believe in torque but have never seen a truck tire shop with a working 400-600 torque wrench. Over tightening can 'yield' the lug nut, stretching it longer and no longer able to keep nut to the tightness setting.
After having two lug nuts overtightened by a truck tire shop. causing them to later break the next time the nut was removed, we started to lubricate stud threads. First, we used gray anti-seize, wiping almost off with a rag after applying. Later we moved to CorrosionX. No more broken studs, at the cost of not being able to correctly torque, as torque specs are for dry threads.
And then there are techs who run the gun pressure to max to remove nuts, but don't realize the 'L' stud is reverse-threaded and they end up damaging stud. Truck tire places are always a risk, as they often put several guys on the job working as fast as they can.
Over torquing has a cumulative effect on the stud. The more times it's done, the longer the stud becomes plus it loses strength. With MBZ cylinder head bolts, we tightened X foot lbs and then tightened a prescribed number of degrees. But before any of this, we had to measure the total length of the bolt as after being overtightened so many times, it would bottom out in the block before pulling the head down correctly. Long bolts were thrown out.
Using Alcoa's recommended torque with n-seize or just taking 20 percent off, is what is needed to keep the nuts on securely without damaging the stud.
Pierce
As I recall from way back when, It was not good to lube a lug nut as that would set you up for the nut to loosen and come off. I suppose that a small amount of non hardening anti-seize or graphite would probably be OK, but for me (old technology) I'll stick to dry (but clean) threads. Also, as I recall, the metal used in the nuts and studs are such that they were designed to be compatible on a dry basis. Have a great day ---- Fritz
So should I remove my tires and wheels and deliver them to the tire shop? I can roll them into the back of my truck.
I have one stemco oil bath cover seeping and an inner seal seeping also. Might as well do both.
I only have a 1/2 torque wrench so I would have build an extension to get proper torque.
How hard is it to source studs and ballpark cost, replace them all while hubs are off or just inspect? Same for lug nuts. If the tire shop strips or damages studs do they really screw yah $$$? Best guess as I am a newbie to big stuff dance. Go ahead and buy a hydraulic press cause I am going to need it?
Asking for sage advice from experienced owners of big stuff as I hope to be doing this for 10-15 years. Probably with the same coach.
Any "A line" tech guy will lube the studs, as that is the correct way. A little grease, gear lube or anti sieze will do.
The Meritor studs are proprietary and when I needed to replace a couple last year I ended up getting them from FOT. That was after I went to two truck places in Knoxville, TN that could order Meritor but the factory said none on hand, Euclid is a big supplier of studs and they had nothing that matched mine, and I think Meritor owns them.
Lubing the stud threads is accepted practice as long as you don't get any lube between the nut and wheel face.
Good Lord proprietary wheel studs aka as a license to steal, hope my old coach has old off the shelf stuff, without sounding political what happened to common standards? Don't go there OPP.
MOT charged $88.93 for each lug bolt, plus $20.87 for the back and front nuts. As mentioned above, they changed 6 bolts between the two front wheels. Craig Power reimbursed me for the total charge from MOT, which included two hours of labor, without even looking at the bill. He just handed to the cashier and asked her to pay me, which she did in cash. I know where I will buy my tires in the future! Actually, I bought some tires from them years ago for our '03 soon after we bought it and the company (Herman Power, Nacogdoches) was a pleasure to deal with then.
Here is a short video of the guys at MOT torquing the lug bolts on my back wheel. There is a lot of noise but you can hear the torque wrench "click" when the set torque is reached.
https://vimeo.com/319138698
Thanks for the info and cost, starts to add up when you have 20 lugs on the front axle and 20 on the back. And mine may look suspect on a 30 year old coach. I think I have time And effort to now do it right.
What is the part numbers for the studs snd nuts,?
For my 2000, U295 MOT had the following part numbers (see attached). I think that got most of the parts from FOT.
20X2136 by MERITOR - AIR DISC BRAKE - WHEEL STUD (https://www.finditparts.com/products/25391/meritor-20x2136)
They still are expensive. Package of 2.
Pack of 4: Meritor Nut 1227Z1378 1227-Z-1378 | eBay (https://www.ebay.com/i/272455496684?chn=ps)
1227Z1378 by AXLETECH - NUT ASSY-WHEEL M22X1.50 (https://www.finditparts.com/products/804693/axletech-international-axlet-1227z1378?srcid=CHL01SCL010-Npla-Dmdt-Gusa-Svbr-Mmuu-K804693-L189&gclid=EAIaIQobChMI-6XN4YHS4AIVg4-zCh30yAtsEAQYASABEgJHIvD_BwE)
When you put the lug nuts back on and start to torque be alert for any studs that are pulling through rather than tightening. Also, look for any stud threads protruding beyond the nut that are longer than the rest, which also indicates the stud is pulling through.
A bit off the topic, my Daughter just had new tires installed on her car. The car needed a service, I said I will pull the wheels, check the brakes, rotors, and lube the caliber pins. When I went to beak the wheel nuts loose, the wheel wrench would not move them. I held the wrench on the nut , my Daughter pushed down using a four foot snipe ( pipe) to break the nuts loose.
A word of caution , check your wheel nuts, you may not be able to loosen them in a case of emergency... After tire repairs, I always loosen , gradually tighten the nuts a minimum of three times, using a star pattern , increasing the Tork each time. Remember, the manufacture designed the wheel wrench so the torque would be correct , even with a "slight" person using the wrench.
Safe travels,
Dave
The 2 cars we have,have the Firestone lifetime rotation,they hand torque the wheels.
Worked on my son's 2013 ford once and it came with these metal coated lug nuts,one or 2 times off and then throw them away
and get a solid set,took all day to get the old ones off.
Here is a screen shot from an Alcoa manual that only gives a lubed value for the two piece flanged lug nut. This is for hub piloted wheels which Foretravel used at least by the 99' model year. According to this chart, the torque value is to be set to 450-500 Ft-Lb.
Don
Consult your specific alcoa manual, as the same one value fits all is bogus at best.
I had 2 damaged bolts a couple of years ago. I found replacements on eBay for $10 per bolt. The tire place ruined the nuts which stripped the bolts and told me it was due to metal fatigue. I'm guessing they were over zealous. They nuts were original so for piece of mind I replaced all of the nuts. Those were also found on eBay. I paid about $100 for a full set. It took a week but I wasn't in a hurry.
The Budd lugs on your coach are the same as millions of over the road trucks. I have buckets of them here and they will go to scrap, The cost to ship them is more than they are worth.