Rear axle causes inside tire wear

[Tgrfan2]

The Dexter 7K rear axle on our 2022 Paradigm 385 FL has worn both rear tires on the inside edge. The front axle tires are about half worn with no edge wear. I just replaced the rear tires. I really don't think taking it to a truck alignment shop is worth it. I would prefer replacing the Dexter 7K with an 8K axle. Has anyone done that?
Looking over the Dexter axles so far, the rear spring-center measurement of 74.5" doesn't show up as standard. The hubface measurement at 92.50' isn't standard either. I did find one option where it appears that I could just replace the tube. I would prefer an 8K with larger drum brakes and oil lube if I could find it. I would replace both axles in that case.
Has anyone had this problem and/or upgraded axles?

 

[George]

I measured my axle alignment and it's off some. I too am hesitant to take it in. Cutting & Welding 😳 I'm not noticing any tire wear though.
Although when I thought back on it I may not have gotten real world measurements. I used the leveling jacks to support the trailer and removed the wheels so I could get to the spindle with a plumb bob more accurately. What I believe I should have done is just hung the plumb bob off the axles outboard of the U-bolts so the suspension was real-world and not just hanging off the leaf springs. 🤷🏼‍♂️
I'm surprised a 385FL doesn't have 8k axles anyway... With a 385FL's GVWR of 19k you may be over 7k on your axles. Have you weighed?
(19,000-20%(pin weight est) = 15.2k/2 = 7.6k

 

[George]

FWIW: Current Paradigm units come with the CURT® Touring Coil Suspension and 8k CURT axles.

 

[BryanValRox]

The Dexter 7K rear axle on our 2022 Paradigm 385 FL has worn both rear tires on the inside edge. The front axle tires are about half worn with no edge wear. I just replaced the rear tires. I really don't think taking it to a truck alignment shop is worth it. I would prefer replacing the Dexter 7K with an 8K axle. Has anyone done that?
Looking over the Dexter axles so far, the rear spring-center measurement of 74.5" doesn't show up as standard. The hubface measurement at 92.50' isn't standard either. I did find one option where it appears that I could just replace the tube. I would prefer an 8K with larger drum brakes and oil lube if I could find it. I would replace both axles in that case.
Has anyone had this problem and/or upgraded axles?

Sounds like you would need a Camber adjustment on the rear axle to correct the tire wear. I would also suggest that you take the weight off of the axles and try to wiggle your tire assemble to see how much play might be in your wheel bearings on that axle.

Can comment on replacing your 7k with 8k, but I would think it would be a bolt on project with the correct springs and dimensions.

 

[UFF]

Had the same issue on my 2023 310RL. Is your trailer level when towing or are you nose high? Do you have to much weight in the rear? I ran a full freshwater tank (extra 800 pounds behind the rear wheels) and had a bike rack with two e-bikes on the rear hitch for 300 plus mine while boondocks in Arizona. All the weight does act like a lever. Every bump causes your rear axle to flatten out and wear the inside tread of your tires on the rear axle. These are just my thoughts on my trailer. Hope you get yours figured out.

As a side note look under your trailer fully loaded and attached to the truck and see if it still is ^ up (axles are higher in the middle than on the ends, as weight is added the axle will flatten out) or flat. If fully loaded and it is straight all the way across it is over loaded or almost over loaded.

Also weigh your set up and find out your weights if you have not already. You might not be overweight but where your weight is could cause issues.

 

[Tgrfan2]

I believe the 385FL switched to 8K axles standard for 2024. Probably tells us something! Sort of like when I complained about the soft close drawers and doors on my 2022. The guy was quick to tell me they didn't come on the 2023s!
The last time I weighed it was with the new truck. The fiver axles were 13,200# with 3250# on the pin so I am getting close to max gross. I don't run any water on the road. The first time I weighed it, I got the axles separate and was shocked at how even in weight they were. I do suspect that the left side could be a little heavier with the kitchen over there. I moved my small air compressor and a few other things back to rt. front storage when I first saw the wear, but as you know once a radial gets a wear pattern nothing helps much. I also have the almost never used Blackstone and air fryer on the right side over the axles. We carry 1000# just in case the wife gets in the mood to cook! I refuse to hook up the Blackstone until she has the food outside.
I suspect it is a case of an axle near limit combined with terrible roads.
My 2026 is taller than the 2018 Ram 3500 SRW. I dropped the Companion to the lowest hole for the 2026 but it still looks a little nose high. I have only 1100 miles towing with it.
I feel certain it is camber wear. Bottom of both rear wheels are "outstanding" like my '98 2500 before new ball joints. I emailed the local truck alignment shop but haven't heard back. I can probably buy an axle for what they will charge to bend this one back to spec only to have it straighten again.
I have a TPMS that shows tire temps and all four run very close. Sun on one side for several hours throws the tires off more than travel. I also check my hub temps when I stop at rest areas and all four hubs run very close. It isn't like they are scrubbing rubber off.
When it stops raining, I am going to take my small laser and place it on both axles and compare the crown. I'll take it off the levelers and level it with the landing gear.
I have been looking at axles again and have found some that are rated 8K and have bigger brakes too. Hub face and spring centers are off standard so I will have to order them "built" out of North Carolina. Hopefully, I can go pick them up. I wanted Dexter with oil lube but they think more of them than I do!
Son in law will be building an equipment trailer with 7K axles before long.

 

[UFF]

My 2026 is taller than the 2018 Ram 3500 SRW. I dropped the Companion to the lowest hole for the 2026 but it still looks a little nose high.

Have the same issue. Went from a 2017 Ford F350 DRW to a 2026 Ram 3500 DRW. Was able to push the pin box up an inch going to measure again next time I have it on level ground. Did a big purge and removed a lot of stuff, then had the idea to weigh all the stuff I took out. It ended up a whopping 65lbs.

If the 2024 had 8k axles Alliance should have the part number or if any 2024s are on an rv lot slide under and take a pick of the axle tag (maybe a 2024 owner will chime in).

Let us know if you figure it out. Fixing to pull mine to Yellow Stone with new tires and an empty fresh water tank. Hoping that was the fix for me. If not I’ll be looking for axles also.