frame bending on long trailer

[TrailerTraveler]

Anybody here know if its common for longer trailers (30+ ft) to bend their frames?

I've got a 2007 model regular pull trailer that is 33 ft long and has bent its frame. The bend is just behind the rear axle and drops about 1" in 3 ft. I've got about 20K miles on it, all on paved roads. I have been bounced pretty good by some of the roads in the northeast once or twice but otherwise nothing unusual. It is loaded to its rated max but no more.

I'm going to buy a replacement unit and I'm trying to decide whether to go with something shorter, maybe 27 ft, or stay with a longer trailer because I like the inside roominess.

[Herk7769]

I need to ask.

What is stored on your rear bumper?
Do you keep bikes back there?
Are there storage areas in the very rear?
Are heavier items stored there?
When was the camper weighed?
Was it over weight?

Ultra-lite frames flex as designed, however they can bend and eventually break from excessive and/or prolonged flexing; just like a paper clip.

[TURBS]

I had 34' tt with no issues.
2006 flagstaff had it 6 years.

Also to get more help with your specific unit you might want to specify your make and model.

[TrailerTraveler]

Hi Herk and Turbo
The trailer is a Rockwood 8315 ultralite. I carry a 30lb bicycle and a trailer spare tire on the back bumper. The rear pass thru storage is where I keep four plastic tubs with miscellaneous hoses, cables, filters, cleaning supplies and a small BBQ.

The last time I weighted the trailer it was 170lbs over weight on the rear axle and 290lbs light on for the front axle. I dropped the hitch height down a notch to bring the front of the trailer down and moved the bike and spare tire into the truck. The damage may have been done by then but 170 lbs doesn't seem like enough to cause this bend.

The rest of the weight data:
Trailer GVWR - 7920lbs, GAWR - 3500lbs (F & R).
Data from weight-in: F axle-3210lbs, B axle-3670lbs, hitch-1280lbs (it has a front kitchen), total-8160lbs (240lbs over).

Turbo,
It's good to hear your 34' did fine for so long. How much did you drive it in that time. Maybe I put too many miles on mine.

[TURBS]

We stay pretty much stay local but I dare say that some county roads in Iowa are in bad shape!
Were out about every weekend from July 1st till September then a couple weekends out of the month till it gets cold.
When bikes on a rack on the rear of a travel trailer get bouncing you have a tremendous force bouncing up and down on your bumper.
You need to multiply that weight at the very least by two!
I once had bikes on the back of mine and the first trip I had 3 holes in the back of my camper from a harlequin bar.
When measured from handle bar to camper at rest they were 22 inches away if that give you any idea how much they move.
One way to tell.,..........
If your loosing end caps in your bumper.

[TrailerTraveler]

Re: Herk's question about heavy things in the tail of the trailer.

The 30 gal fresh water tank is also back there. I usually have about 5 gal in it but have driven with it full 4-5 times when I expected to dry camp in a state park or Wally world.

[TrailerTraveler]

That's a lot of camping Turbo, and some big time bouncing. The leverage of the bike weight would be significant with that kind of banging around. I know the bumps we hit on several of the two lane roads in the NE were down right violent. The kind of thing where you get out and walk around the rig to make sure all the pieces and parts are still attached. So my bike back there could be a bigger factor than I was thinking it was.

I have not lost a bumper end cap yet but it makes sense that significant/damaging bouncing would cause that. Good tip, thanks.

[TURBS]

no problem . I hope its nothing to serious.

[VinceU]

Originally Posted by TrailerTraveler

Anybody here know if its common for longer trailers (30+ ft) to bend their frames?

I've got a 2007 model regular pull trailer that is 33 ft long and has bent its frame. The bend is just behind the rear axle and drops about 1" in 3 ft. I've got about 20K miles on it, all on paved roads. I have been bounced pretty good by some of the roads in the northeast once or twice but otherwise nothing unusual. It is loaded to its rated max but no more.

I'm going to buy a replacement unit and I'm trying to decide whether to go with something shorter, maybe 27 ft, or stay with a longer trailer because I like the inside roominess.

Wondering, have you checked into a frame shop? If not to repair the bend, just maybe reinforce the area and move the stressed site with brackets. Appears it wan't so much the load on the axle was the problem appears the weight behind the axle acting as weighted lever. Not common but easy to fix.

[Herk7769]

Originally Posted by VinceU

Wondering, have you checked into a frame shop? If not to repair the bend, just maybe reinforce the area and move the stressed site with brackets. Appears it wan't so much the load on the axle was the problem appears the weight behind the axle acting as weighted lever. Not common but easy to fix.

A frame shop would be my next stop. They have the tools to straighten your frame and beef up the now weak parts (from having been bent).

The bike is a killer; put a load at a significant distance from the rear axle and you have the lever arm from hell.

30 pounds of bike and mount might not seem like much but add the spare tire and bounce it up and down across 10 or 12 feet of thin metal welded into a frame and you get a tremendous amount of bending force at the axle attachments. Ultra-lite frames are not extruded I beams, they are welded up from strap steel.

Have your DW drive over that road while you follow behind in the car (at a safe distance) and watch that bumper, tire and bike rack. Be in for a shock.

[TrailerTraveler]

Thanks for the responses guys.

Checked with a chassis shop and they wanted $5K+ to straighten & reinforce the frame (both sides). The RV repair shop wanted $5K+ to get the house square and sound again. Not only a big expense but it seemed likely there would be on going problems after the repair. So, I got rid of it. Told the buyer about the problems before closing the deal. Felt really lucky to get any money for it at all.

My main concern is making sure that 30+ft trailers aren't anymore prone to bending their frames than shorter trailers. Sounds like they aren't as long as you take care of them.

[TURBS]

Yes I just think you need to watch your loading limits.
And always be careful when loading anything on the rear bumper.
Have you found a new unit?

[VinceU]

Originally Posted by TrailerTraveler

Thanks for the responses guys.

Checked with a chassis shop and they wanted $5K+ to straighten & reinforce the frame (both sides). The RV repair shop wanted $5K+ to get the house square and sound again. Not only a big expense but it seemed likely there would be on going problems after the repair. So, I got rid of it. Told the buyer about the problems before closing the deal. Felt really lucky to get any money for it at all.

My main concern is making sure that 30+ft trailers aren't anymore prone to bending their frames than shorter trailers. Sounds like they aren't as long as you take care of them.

Gulp, well I guess that's good. The three stages of steel failure, you probably know, are flex (bends and returns), yield (when it remains bent) and total failure (distort and buckles). Simple solution try to keep heavier loads between axles. Overhung wt. should be minimal

Heavy loads on commercial trucks are always centered over axles.
Long M/H's, trailers and trucks do not fail when loaded properly.

Longer is better, I did mine in four steps!

[TrailerTraveler]

I have, indeed, found a new unit. We're buying a new Rockwood 8315BSS front kitchen Signature Ultralite from RVDirect. We really like the roominess and layout of front kitchen trailers. Hope to pick it up in early Sept.

[Broadway Joe]

While approaching San Antonio last monday, Traffic backed up and was necessary to move into left lane and one hundred yards ahead was an 18 wheeler with the trailer folded up right behind the dolly or park wheels. Never saw a trailer fail like that.