Dexter Axle wheel studs

[Mont_G_J]

My 5th wheel has 5200lb Dexter axles with 6 wheel studs that are
1/2 x 20. On one occasion all six studs broke and I lost the right rear wheel. On three other separate occasions, I have had one or two broken studs that are always on the rear wheels. I check the 120 lb torque often and have used two different torque wrenches.
My question is, does anyone know if there is a harder or stronger grade stud available for Dexter axles?

[Passin_Thru]

Get the size and buy them a NAPA. Mine broke and I replaced them w/NAPAs and torqued to 90 ft lb. I have an Arctic Fox TT and it weighs 9K.Bolts are torqued to stretch them so you have to know the hardness or class of a bolt before you torque it to anything. Also there are torque tables for bolts and torque wrenches are supposed to be calibrated. How do you know you are putting 110 ft lb to the bolt?
I hauled new TTs and the Mfg always said the front of the trailer should be lower than the rear by 2 inches on bumper pulls.

[fj12ryder]

"Some additional info that I should have supplied in my OP is; I changed the standard lug nuts to the chrome acorn type."

Surely this wasn't before you started breaking studs. If you did this and then started breaking studs shortly after...

[mapguy]

Mont G&J wrote:
Too many good suggestions to reply to each poster, but I sure appreciate all of your inputs. Right now the trailer is in storage, so information will provide me a good starting point this spring. I’ve had the trailer since new in 2005, the first time I had a stud failure was 2008 on the right rear. Since then I usually break one or two on the Rt rear when I travel from Montana to Texas. This last trip the Lt rear broke one.
Some additional info that I should have supplied in my OP is; I changed the standard lug nuts to the chrome acorn type. The trailer is about two inches higher in the front. The axles are 5200 lb, and the scale weight on both is 9250, I didn’t weight each axle separately, but I should have.

You are stressing the rear axle/suspension greatly with the nose high setup. That in combination with over torqueing the lug nuts is probably causing this problem.

For best ride -the trailer frame should be level when hooked up to the tow vehicle. Trailer frame level puts the rear axle suspension in a neutral position allowing maximum suspension travel. With nose high the rear axle has very little suspension travel to absorb roadway defects before bottoming out. it is easy to see when hooked up -look at the position of the equalizers and spring hangers. Set up right on fairly level straight area -proper set-up will have the equalizer in a neutral position.

I agree with another poster in the thread - only re-torque lug nuts at 50 or so miles after install.

[Lynnmor]

The manufacturer of the aluminum wheels I have calls for 100 lb ft.
My snowmobile trailer with steel wheels calls for 85 lb ft.
Both use 1/2-20 studs.

[Mont_G_J]

Too many good suggestions to reply to each poster, but I sure appreciate all of your inputs. Right now the trailer is in storage, so information will provide me a good starting point this spring. I’ve had the trailer since new in 2005, the first time I had a stud failure was 2008 on the right rear. Since then I usually break one or two on the Rt rear when I travel from Montana to Texas. This last trip the Lt rear broke one.
Some additional info that I should have supplied in my OP is; I changed the standard lug nuts to the chrome acorn type. The trailer is about two inches higher in the front. The axles are 5200 lb, and the scale weight on both is 9250, I didn’t weight each axle separately, but I should have.

[TundraTower]

2 weeks ago I had my TT axles upgraded with 5,200 lb Dexters and I have stacks of reference material on my desk and computer as I recalibrate my knowledge base for the new components.

The wheel section of the Dexter service manual calls for 90-120 FT-LBS for wheels made by Dexter prior to 2004. They quit making their own wheels then, and now call for simply a MAXIMUM TORQUE by stud size. They list 120 as the MAX for 1/2' studs.

I agree with others in thinking 120 is just too much. My previous 3,500 lb Lippert axles called for 100 FT LBS on a 1/2" stud, and the coach sticker on my 4 year old trailer also called for 100 FT LBS.

I have had a lot of trouble with the lug nut threads distorting. In fact it is rare for my to re-use a lug nut because once used they can't be spun back on by hand. I carry a big bag of new lug nuts and have started experimenting with other suppliers.

For this reason, I'm staying in the 90 FT LB range. And yes, I use a torque wrench that was calibrated in December with no corrections needed.

[myredracer]

Too high a torque value would be the first suspect. Do the wheels spin true? (You would likely notice uneven tread wear tho.) I would inspect all other studs and maybe replace all of them. Maybe rotate the wheels (front - rear). Have you ever had your torque wrenches calibrated? Maybe balance the wheels/tires and drums/axles. Are the studs seating properly? Are the nuts seated properly in the wheels? Nuts possibly bottoming out?

Wheels look like aluminum and I would say 120 ft-lbs is just too much. If one stud does fail, it can cause others to fail soon after that so may not necessarily be a problem with all 6 studs. Original wheels? Do you maybe hit lots of potholes & speed bumps? How old is the trailer and wheels/tires? Bearings not loose? You have shocks which should help the situation but are they working okay? On a multi-axle trailer each axle has a different turning radius around corners and one axle (or two on a triple axle) will get the tires dragged across the pavement but I doubt this is of much significance. Have you ever weighed the trailer to see what actual weight the axles are carrying? (Maybe side-side weighing would help too.)

[p220sigman]

You didn't indicate that it is always happening on the same wheel or not, but if it is, I'd look closely at that hub/wheel/suspension to see if there is something putting extra stress on that particular wheel or maybe even see if there is some maneuver you are performing when driving that may be stressing that particular wheel. If it is happening on both rear wheels, I'd agree that it is probably an overtightening situation. Once you verify the lugs are the proper ones for the wheels, I'd probably back off to 80 or 90 lbs and see if it continues to happen.

[time2roll]

If going to the max 120 do you loosen each lug and then tighten it?
Same after a shop does work you need to loosen them and torque up to spec.
If you go to 110 you should be able to set them once and then just do a click check to avoid a loose lug.

Have you had any studs you replaced and controlled the torque break?
Just takes once to over torque and weaken the stud. Even with correct service, torque and use these weakened lugs may eventually break.

If you replace one stud on a wheel I recommend replacing them all.

[Charlie_D_]

fj12ryder wrote:
I know you have probably checked, but maybe a double check to make sure the lug nuts match the profile of your wheels' lug nut openings. Maybe somebody screwed up somewhere and they mismatched the wheels/hubs. Maybe your wheels are lug centric and your hubs are hub centric.

OP pay attention to this. Some rims have deeper recesses than others. The taper of the lug nut must be the same as the rim AND be sure the corners of the lug nuts do not contact the rim. Only the seat. I have several studs break and found that the seats did not contact because those corners on the long acorn nuts made contact before seating. everything was tight and torqued properly but after a few miles down the road the rims came loose.

[Mont_G_J]

I want to thank everyone for their input. Those of you that think 120 lbs torque may be too much gave me cause to think about that. The printed page in the owners manual reads “Torque 110 lbs”, however, a loose change sheet was inserted in the booklet that changed the value to 120 lbs. My 23 years military training is to always go by the book, not your brain may be the cause of all my grief. 120 lbs may be stretching the studs to their break point.
When the studs break, it’s a clean break close to the drum. I’ve never had a loose lug nut or wheel.
My replacement studs have come from Dexter Axle, and, an online RV Trailer parts supply.
I try to limit the maneuvering angles I put the trailer into, I’m sure that’s when the most side force is acting on the wheels.

[j-d]

Ron3rd wrote:
"an over-torqued bolt is already half broken"

Closely related to "tighten till it breaks then back off a quarter turn."

[Ron3rd]

Just my opinion, but 120 ft lbs sounds like way too much for a 1/2-20 stud. On my old trailer with that size studs I believe the torque was around 80 ft lbs.

Remember the old saying, "on over-torqued bolt is already half broken".

[j-d]

Tandem (and triple) axle trailers have a hard time with wheels and lugs because of the racking forces they experience being turned tight on a surface with good traction. Do you store or camp where you turn the trailer to nearly jackknifed on a paved pad? That's murder on everything down there, axles an all.

Are you replacing studs (and presumably nuts) only, or the entire hub? If studs, are they still a tight press fit in the hub? You should be able to get new studs from a quality American Manufacturer (not an American re-boxer of Pacific Rim junk). And of course match nut profile to the wheel.

Is the wheel damaged? This usually happens on the left side, since driving tends to keep the right side tight and loosen the left side. If the wheel holes are hogged out, and maybe the nuts aren't right too, seems possible to me to bottom the nut to, or right against, the hub flange, leaving not much clamping and centering action for the wheel itself.