Another reminder [U bolts]

[NCFischers]

Just another reminder to check your u bolts. I was doing my trailer pre-check before we head to the Mid-Atlantic Rally. Four of our u bolts needed tightening. There was only a few thousand miles since
I last checked them.

[camper4]

What is the torque they should be at?
Thanks

[NCFischers]

65 foot pounds

[Lambchop]

When I changed out my Mission Tires three weeks ago, I checked mine for the first time.
Two of the U bolt nuts where just sitting there. I had to turn them by hand to tighten before I could torque them! About 2 turns......

It's hard to believe that this condition doesn't make some of us think before we pull our Montana's down the road!

Roy

[richfaa]

I had the U bolt disaster happen last year.. Note that if you read the book, which I did not, the maint procedure is clearly outlined. It was a expensive fix and clearly my fault. I did not read the book.

[camper4]

Thanks. My u-bolts and nuts are rusted from time in the Florida Keys. I will put a torque wrench on them next week when I check on the brakes.

[CORattler]

I'll add that to my torque check list. Thanks for the "heads up" !!

quote:Originally posted by NCFischers

Just another reminder to check your u bolts. I was doing my trailer pre-check before we head to the Mid-Atlantic Rally. Four of our u bolts needed tightening. There was only a few thousand miles since
I last checked them.

[KTManiac]

quote:Originally posted by NCFischers

65 foot pounds

I thought that the Dexter rep at the '09 Fall Rally said that they changed the value to 70 ft/lbs. Pretty sure that I didn't just dream that up.

He also mentioned something about that they were testing and maybe soon to change from round u-bolts to a flat version (cross-sectionally, flattened on the side of the bolt where it contacts the axle) for better component reliability and stability. Not sure what has happened with that tid-bit of info, guess I'll have to call Dexter and find out for sure.



UPDATE:
Just got off the phone with dexter, and yes, they upped the torque to 70 ft/lbs.

Also, they are now using the new flattened u-bolts with much success!

Looks like I'll be calling Dexter to order some new u-bolts.

He said to make sure to tighten the nuts with progressive torque values, in a criss-cross pattern with the axle un-weighted to the 70 ft/lb value, and then again after the axles are supporting the weight of the trailer.

[NCFischers]

From what I understand, Dexter recommends 60 to 70 pounds. I split the difference.

[NCFischers]

Is that 70# with the flat u bolts or all u bolts??

[KTManiac]

quote:Originally posted by NCFischers

Is that 70# with the flat u bolts or all u bolts??

Jim, I would say it is for all of them, because that is what the Dexter technician told me to torque mine to when I was at the '09 Fall Rally, and he knew that I had the round u-bolts.

That's the best answer that I can give you without another call to Dexter, and I think that it is probably too late to call them again today.

[8.1al]

If I had my u-bolts torqued to 65 ft. lbs and someone told me it was suppose to be 70 I wouldn't lose any sleep over it. However if I had torqued the u-bolts and a few thousand miles later they had to be re-,then I would be concerned. Our rig is 6 1/2 years old, has traveled many miles and when I checked the torque last year I had only one nut that moved just a teeny bit. If mine needed re-torqueing I would be looking at a new,good, torque wrench or new u-bolts.

[pvcoach]

We were bit by the loose U-Bolt bug two weeks ago. I don't know why, but I had missed (or dismissed) earlier posts on this same subject! The U-bolt nuts on the rear, passenger side of our Monty had worked their way loose. When approaching a toll booth on I-44 south of Oklahoma City, I heard a quick squeak when I applied the brakes but didn't see anything wrong in my rearview mirrors. As we got closer to the toll booth, I noticed the trailer wasn't tracking behind the truck as usual but still couldn't see what was wrong. Paid the toll, then got out to see what was going on. WOW! The rear wheel on the drivers side of the Monty was angled to the front wheel. Looking underneath, I immediately saw the axle had moved all the way back to the rear shackle on the passenger side! No damage to the Monty, but certainly could not move forward through the toll booth. A passing motorist slowed down and let us know that something had flown off on the highway as we approached the toll booth. I walked back up the highway and retrieved two pieces of my passenger side leaf spring. All parts in hand, the toll booth closed and barracaded off, Oklahoma Highway maintenance and I spent four hours getting the axle moved back into position and bolting it back into place so that we could continue on to an RV repair facility. We came out of this one very well, I just wish I had seen the earlier posts and/or paid more attention.

[KTManiac]

Wow, that could have been a whole lot uglier! Imagine that happening at 60 MPH.

You are extremely fortunate my friend.

[Concrete John]

Hi, there , new to the forum , i thought i would chime in , before re-torqing your U-bolts, especially if they are rusty , make sure you loosen them first!!! then torque 1/2 the recommended ft/lbs, in sequence (stagger the pattern) then torque again to the spec. This is important , as you do not want to over torque and cause "bolt stretch" condition . Over torqing could cause the bolt to snap, or stretch, weaking it's clamping force.

[Tom S.]

quote:Originally posted by Concrete John

Hi, there , new to the forum , i thought i would chime in , before re-torqing your U-bolts, especially if they are rusty , make sure you loosen them first!!! then torque 1/2 the recommended ft/lbs, in sequence (stagger the pattern) then torque again to the spec. This is important , as you do not want to over torque and cause "bolt stretch" condition . Over torqing could cause the bolt to snap, or stretch, weaking it's clamping force.

First and foremost - welcome to the board! Now, on to the topic: I've never heard of loosening them before re-torquing. I'm not doubting you, just saying I've never heard of that before.

BTW: interesting user name! It can be taken in more than one way...

[Concrete John]

Thanks Tom, great site too . The reason for loosening the bolts first , is to insure there free to move, rust, road grime, thread lockers(glue for bolts) can directly affect torque values,therefore make sure the fastener is free.Also some manufactures insist on dry clean threads before torqing( no oil grease or lubricants) as this will also change the torque value.The days of the ole "backyard mechanic are long gone, you know the guy who just cranks the bolts tight by hand .Technology has come along way, manufacturing etc, hence the need for accurate torque values.And regular inspections for trouble free Rv'ing. (i'm a former Mechanic)

[Concrete John]

Oh by the way ,, ha ha my nic >> concrete John I'm a finisher , coloured /stamped /textured concrete , seemed only fitting !!Been at it since i was a teenager, can't seem get away from it , so i've made my business .( acually have a few trades under my belt) Cheers John

[drsmart]

With this issue of U-bolts loosening at times, would it be advisable or acceptable to use medium Lock-tite on the nuts after they are torqued?

[Concrete John]

Hi drsmart,I would not recommend any type of thread locker on this application, reason being , there are alot of stresses and flexing in suspension systems (especially if your steady over the road)I would suggest if your always travelling 1) monthly checks 2)upgrade to stronger bolts, lock washers 3)After torqing, spray a high quality rust proofing , (not spray tar) i use a producy called "fluid film" hard to wash off and does'nt "throw off",rust protection , i spray that stuff on any metal area's undernieth, slide cylinders frame rails , you ,name it , and die electric grease all electrical connections. Geesh you've got me going . john