Bent axle.

[36guy]

Bought a 2019 Imagine brand new, a 2600 RB, weigh around 7000 lbs dry. First long trip, springs gave out, went flat, Grand Design replaced those under warranty, next was the rear axle bent. Turns out, they were 3500 lb axles, 2 3/4 inch tube. After much argument, Grand Design determined it was my fault, even though, a year later, they upgraded the suspension to 4400 lb springs and three inch axles, on the same model trailer. Fine, we took it upon ourselves to upgrade the suspension with 6000 lb axles, wet bushings and an EZ flex kit. Two years, a few trips, happy happy. Until, we just returned home from a trip to northern british columbia, and somewhere on the way home around 8 hours from home we bent another axle, driver side rear, toed out 1/2 inch eating the tire after 8 hours. I hit nothing, no marks, nothing to show either on truck tires or the front axle. Rough roads, lotsa frost heaves, some unavoidable surprises, but really no clue as how this has happened. I'll add, been pulling trailers-fifth wheels forty years, drove trucks for the same forty years.

[36guy]

Yep me too this came as a surprise. I can blame it on very rough roads, I doubt I'll have an issue again.

[Bionic_Man]

I'm going through an axle issue on the trailer of my fishing boat right now. Trailer tech (who I have known for years) blames mine on the terrible roads we have around here. I'm surprised that you're having trouble with your overbuilt replacement axles.

[36guy]

Repaired, bent between the spring mount and the backing plate for the brakes, a distance of about six inches. Done by a shop that builds trailers commercially, his best guess was a bad hit from a pothole or frost heave, he's seen it before. Incidentally, he had three more new travel trailers behind mine, to replace bent axles, and that was just today, says he does a lot of replacements on travel trailers. Regardless of the manufacturer, they're not built heavy enough anymore.

[JBarca]

Yes, please report back on the findings. Very curious about this. 1/2" toe out, wow...

When looking at the frame behind the rear hangers, look for this. This is in the advanced stages after the frame ratcheted itself down over time, but this lower flange bend is what started my issues after that pothole interstate.

I reinforced the hangers and the lower flange on the outside long ago to remove the I-beam web cracks that can happen with this setup. Mine web never cracked, as I was proactive in reinforcing it. The outside reinforcement helped the outside part of the lower flange resist the deflection, but the inside with where the larger issue started.

The outside of the left rear hanger. The slide room is just above this hanger.




The left rear hanger area inside the frame shows a distorted lower flange. This is a problem if yous have any deflection in this area. Put a straight edge on the lower flange and see if it is straight.


Using a straight edge across the area


This amount of bump is a problem that will get worse under normal towing in the future.




I hope this helps and you do not have this bent lower flange issue. Bending that heavy axle toed out that far, something big happened or lots of little to medium hits.

John

[canoe_on_top]

Frost heaves are an axle killer. Some years ago, in the Yukon, I had to replace both axles on my Nash trailer after a section of the Alcan highway.Should have gone slower. You often don't see the frost heaves until you are right on them.Replacing two axles in Whitehorse is not cheap. Nash trailers are pretty study but, that's a rough road.

[Grit_dog]

I’ll take bad luck and bent spindle for $200 Alex….
In my experience one wheel toe in or out is usually a bent spindle/assembly. Negative camber is usually a bent axle/tube.
I’ve beat on, farked up and fixed a lot of trailers.

[36guy]

Yes, mine is the exact same as the brochure, same weights, yes it's the rear axle, as said, left rear tire is toed out 1/2 inch, skinning off the inside of the tire, no wear on the opposite side, only the driver side rear. I'm well versed on mechanics, been a car builder for forty years, 13 hot rods under my belt. I'm just mystified how an axle this strong could give me trouble.

[36guy]

Yes, brakes are now 12 inch, everything was changed and upgraded. I may have a bent spindle, I can't see deflection in the axle, tomorrow it hits the shop, I can't find anything else wrong, so it must be axle related. I'll post tomorrow when the pro's look at it.

[JBarca]

Hi 36guy,

You stated this

36guy wrote:
Fine, we took it upon ourselves to upgrade the suspension with 6000 lb axles, wet bushings and an EZ flex kit. Two years, a few trips, happy happy. Until, we just returned home from a trip to northern british columbia, and somewhere on the way home around 8 hours from home we bent another axle, driver side rear, toed out 1/2 inch eating the tire after 8 hours. I hit nothing, no marks, nothing to show either on truck tires or the front axle. Rough roads, lotsa frost heaves, some unavoidable surprises, but really no clue as how this has happened.

I looked up that model. Is it this one? https://www.granddesignrv.com/travel-trailers/imagine/2600rb

I know that may be a newer model, but is the floor plan the same and the GVWR of 7,850#?

6,000# axle tubes on a camper that small of a trailer should have been overkill, but the dynamic shock into a camper from potholes and other road hazards at highway speeds has damaged campers before.

Was the axle that was bent the rear axle? You did not state that; I gathered that the front axle was not bent, meaning it has to be the rear axle.

By chance, can you post pics of the following?

- The bent axle tube is trying to show the direction of bending.

- Look at the bottom flange on the I-beam frame behind the front and rear hangers. Look for "any," and I mean any distortion on that bottom flange. If that lower flange has any slight bend, please show that in pics.

- A picture of the axle tube sticker, assuming it has one.

- A general picture of how the hangers are mounted to the lower frame flange.

- Confirm what overall height (top to bottom of flanges) of the I beam main frame rail.

While I can't tell you what you may have hit, I may be able to help with what else may be an issue if you actually bent a 6,000# rated axle tube.

I have 2, 6,000# alxe tubes on my 10,000# loaded camper. ( upgraded them from 5,200#) A pothole-laced interstate in NY started to bend my main frame aft of the rear spring hanger. I had 15 miles of living ..ell traped doing 50 mph on a double-lane highway with a semis whizzing by at 70 mph in the left lane. No place to even pull off until the exit came. What the truck missed, the trailer hit. The tire spacing spread is different between truck and trailer.

In my case, I never bent the axle, but the constant jolting of the potholes started lower flange deflection on the main frame just behind the rear spring hanger. And on an I-beam frame, the flanges take most of the load. Once they are compromised, normal towing deflection will keep bending the frame down. After enough miles, the slide no longer fits in the hole in the side of the camper. The hole in the camper wall opening ends up a parallelogram, and the slide room has 4 square corners. When the parallelogram gets to be too much, the slide will not mechanically fit in the hole without tearing into the slide roof.

Suggest you check your frame now for any slight deflection of the lower flange. It can be reinforced before more damage comes.

Also curious, if you were on 3,500# alxes and went to 6,000# axles, did you change the brake drums? 3,500# and 4,400# axles can have 10" brakes. 5,200# and 6,000# axles have 12" brakes. If by odd chance, you have 10" brakes on an actual so-called 6,000# axle, something does not add up. They are not normally made that way; the bearings and spindles are all different.

I am trying to learn from your misfortune.

Hope this helps

John

[Lantley]

"Rough roads, lotsa frost heaves, some unavoidable surprises",

I don't think I would include that statement in any warranty claim!

[Fisherman]

Rough roads, lotsa frost heaves, some unavoidable surprises, but really no clue as how this has happened. There's your answer