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The trailer is also supported at the tongue by the truck. So to have over 5995lbs on a 17MKE would be quite a chore IMO. My 2600RB loaded for a week long dry camping trip and with full water is at 6500lbs.
Three quarters of the way through our Alaskan trip I had to have four new tires fitted, the originals were Goodyear Endurance and they wore just like yours, had 10 ply ones installed, now home took the trailer to a big rig axle/suspension place and after pulling the wheels they found all of the suspension bushings failing. the guy said that was all he could see wrong. I was led to understand that these were not wet bolts so could not be manually lubricated. The mechanic told me that some were brass and some nylon and they had the nipples for greasing. My model and year according to my research did not come with wet bolts, I have about 13,000 miles on the rig. The roads up to and in Alaska are terrible in places so I can understand the higher wear but to fail like that and to have a mix and match set of linkage is just wrong. $1000 for the tires and I pick up the trailer later today so who knows what its costing me to install brass sleeves and wet bolts. My tires ended up bald on 60% so I had to do something. For info the tires that were fitted are Sailun, another Chinese tire but the trailer guy that I have the trailer with says that a lot of the tractor trailers use that tire as it is well proven and strong.
Steve and Tammy Robinson - 2020 Reflection 315RLTS, 2020 RAM 3500 6.7 Turbo Diesel SRW, Short Box.
I just talked to the frame/axle shop in Farmington NM. They claim that they can re bend the axles. Have you ever heard of that? The engineer in me says this would ultimately weaken them and they would not be as strong as before. Ill have them look it over next week and I may have them beef up the frame in spots like where the rear jacks now just attach just to one side of the frame flange and double check the spring perches, etc. Possibly add wider pads for the sumo springs
In researching I can also do complete replacement axles from Dexter in either 5200lb or 6000lb Both use the 655 Hub Group for D52/D60 which comes with the 1/2" studs in the 6-5.5 bolt pattern. I currently have the 655 grou0 hub for D44. The only difference between the D52/D60 hubs is bearings are larger for the 6000lb. Spring packs are the same length and width but stack height increases from 1.42 I have now to 1.44 for the 2600lb and 2.01 for 3000lb. Free arch height actually decreases as you go up in capacity. 3.12 for 2200, 3.0 for 2600 and 2.83 for 3000. Remember we are talking spring capacity, multiple by 2 for the total axle capacity. Tube diameter stays the same i think, but not sure on wall thickness. I have not found that information yet. The upside to axle replacement is they come with the 12" by 2 brakes, not the 10" by 2.5 I have now. Here is the catalog I am using. Lots of options I can choose when specking my new axles - if needed out. I will be sticking with electric brakes. https://www.dexteraxle.com/user_area...LIT-122-00.pdf
Thoughts are welcome
Thanks
Keith
2018 Reflection 150 Series 220RK 5th whee, Star White 2022 F350 King Ranch CC Long bed (HAL) (CCC 4062lbs), B&W 25K OEM Companion,. SteadyFast system, Trailer reverse lights, rear receiver spare tire holder, storage tube, sumo springs, Victron MultiPlus 12/120/3000, Solar, Custom 6K axles upgrade, and other modifications.
I just talked to the frame/axle shop in Farmington NM. They claim that they can re bend the axles. Have you ever heard of that? The engineer in me says this would ultimately weaken them and they would not be as strong as before. Ill have them look it over next week and I may have them beef up the frame in spots like where the rear jacks now just attach just to one side of the frame flange and double check the spring perches, etc. Possibly add wider pads for the sumo springs
In researching I can also do complete replacement axles from Dexter in either 5200lb or 6000lb Both use the 655 Hub Group for D52/D60 which comes with the 1/2" studs in the 6-5.5 bolt pattern. I currently have the 655 grou0 hub for D44. The only difference between the D52/D60 hubs is bearings are larger for the 6000lb. Spring packs are the same length and width but stack height increases from 1.42 I have now to 1.44 for the 2600lb and 2.01 for 3000lb. Free arch height actually decreases as you go up in capacity. 3.12 for 2200, 3.0 for 2600 and 2.83 for 3000. Remember we are talking spring capacity, multiple by 2 for the total axle capacity. Tube diameter stays the same i think, but not sure on wall thickness. I have not found that information yet. The upside to axle replacement is they come with the 12" by 2 brakes, not the 10" by 2.5 I have now. Here is the catalog I am using. Lots of options I can choose when specking my new axles - if needed out. I will be sticking with electric brakes. https://www.dexteraxle.com/user_area...LIT-122-00.pdf
Thoughts are welcome
Thanks
Keith
Keith,
Yes its done all the time. Frames too. Its a personal choice if you want to go that route or to replace. For moving up in axle size, you may want to run that past GDRV to be sure the frame can handle the higher capacity axles and springs.
Bending beam axles to achieve alignment is common practice in heavy trucks and trailers. But these have much heavier gauge axle tubes. I have heard of bending the thin wall tubes on RV axles, but (personally) I would be cautious with this. The other benefits of upsizing to new axles and brakes would take me in that direction . . .
Yes its done all the time. Frames too. Its a personal choice if you want to go that route or to replace. For moving up in axle size, you may want to run that past GDRV to be sure the frame can handle the higher capacity axles and springs.
Jim
Good point. I'm not trying to changing the GVW, just bullet proof the suspension. but the axles and springs will weight more. They would probably direct me to Lippert as thy made the frame and installed the suspension components.
Ill look into it.
TedS
I have done it too on bridges where beams have been hit by over height vehicles., but at some point you need to replace. Even after being straighten out most get backing plates added to the repair area, either bolted or welded depending on the bridge steel.
Thanks
Keith
2018 Reflection 150 Series 220RK 5th whee, Star White 2022 F350 King Ranch CC Long bed (HAL) (CCC 4062lbs), B&W 25K OEM Companion,. SteadyFast system, Trailer reverse lights, rear receiver spare tire holder, storage tube, sumo springs, Victron MultiPlus 12/120/3000, Solar, Custom 6K axles upgrade, and other modifications.
Bending beam axles to achieve alignment is common practice in heavy trucks and trailers. But these have much heavier gauge axle tubes. I have heard of bending the thin wall tubes on RV axles, but (personally) I would be cautious with this. The other benefits of upsizing to new axles and brakes would take me in that direction . . .
Rob
Thanks Rob. Question - going to 6K axles/springs be too stiff for my rig? I can always take a leaf out of the stack or use the 5200lb axle springs. I just like the idea of the larger bearings/spindle the 6000lb has.
More research to do. I'm trying to get pricing ahead of time before having the axle/frame shop look at it.
Thanks again
Keith
2018 Reflection 150 Series 220RK 5th whee, Star White 2022 F350 King Ranch CC Long bed (HAL) (CCC 4062lbs), B&W 25K OEM Companion,. SteadyFast system, Trailer reverse lights, rear receiver spare tire holder, storage tube, sumo springs, Victron MultiPlus 12/120/3000, Solar, Custom 6K axles upgrade, and other modifications.
The biggest problem with going too strong on the springs is that the entire trailer gets a rougher ride. Ideally, the springs should use their entire range of travel to absorb road impacts. Static loaded arch height should be somewhere near 50% of total spring travel. About 1.5” of 3” for our RV trailers. If the springs are stronger than this, less spring range will be exercised. This was a much-discussed topic a few years back on this forum and the previous one. You may want to dig back through those discussions.
The “fix” for flattened springs (that were originally at the correct loaded arch height) is not stronger springs . . . it is better quality springs.
Wondering if the Sumo Springs+Leaf springs put the axles into failure? Having bump stops would be nice but working with an equalizer type system may not be possible to have them respond properly at different equalizer angles. Slipper springs with a proper jounce bumper could work but this could also be another case for the MorRyde IS when thinking about traveling to Alaska.
The action of the Sumo springs against the axle would be no different than upsizing the leaf springs. Both have the same connection point to the axle. I think your theory is that if the springs were stiff enough, an impact load could bend the spindle because the spring(s) did not absorb the load. I don’t think the Sumos are anywhere near that stiff. There are many examples of where catching a curb or pothole can bend one spindle even with OE springs. If the Sumos were causing this problem, it should be showing up in uneven tire wear on all tires.
Some more information to help in spring and axle selection if I have bent them. When I first got the trailer I weighed it with full fresh water and black and gray tanks 1/3 full and packed for a weeks trip. Asles had 6800 lbs (trailer on scale truck off) I used a local Agg scale. For the Alaska trip I probably had another 1000lbs of stuff (second spare, can goods, bottled water, etc). So if all was on the axles I was only at 7800lbs with an axle capacity of 8800lbs total. Not knowing how the suspension acts when slightly out of level, what additional load might the rear axle have seen? The spindels for the 5200 and 6000 lbs axles appear to be the same with different outer bearings. Both axles have the same ID dimension that are significantly larger ID Example ID for the inner 5200/6000 is 1.75. MY 4400 axles has an inner bearing of 1.377. Outer bearing ID is the same for all at 1.25.
So lets say on average I have 7500 on the axles - is having 12k (2 6k axles) capacity overkill or would the 5200 lb axles be better - 10400 capacity? From what I can tell there is only about $400 price difference for the set. I would still use the Sumo springs as a bumper stop.
BTW I will be installing the protective metal sheeting above the tires as the rocky road sections did wear the fabric through. The Sumo springs worked as I had hoped as I did not have any tire contact with the underside of the trailer.
Lots to do tomorrow and phone calls to make. I am going to call Dexter as I believe I am still under thier 5 year warranty, but I could be wrong.
Thanks Keith
2018 Reflection 150 Series 220RK 5th whee, Star White 2022 F350 King Ranch CC Long bed (HAL) (CCC 4062lbs), B&W 25K OEM Companion,. SteadyFast system, Trailer reverse lights, rear receiver spare tire holder, storage tube, sumo springs, Victron MultiPlus 12/120/3000, Solar, Custom 6K axles upgrade, and other modifications.
The action of the Sumo springs against the axle would be no different than upsizing the leaf springs. Both have the same connection point to the axle. I think your theory is that if the springs were stiff enough, an impact load could bend the spindle because the spring(s) did not absorb the load. I don’t think the Sumos are anywhere near that stiff. There are many examples of where catching a curb or pothole can bend one spindle even with OE springs. If the Sumos were causing this problem, it should be showing up in uneven tire wear on all tires.
Rob
Rob,
I believe the Sumo Springs are a good idea to try and mitigate spring overtravel, but I'm also wondering how they responded when the system may have bottomed out. If they compressed enough to prevent spring overtravel, the load may have overstressed the axle. Or they actually prevented damage that could have been worse. It would be interesting to put one in a fixture to see the result in a full compression. Either way, the total spring rate of the system has been modified and I'm curious in how much that may be.
Agree axles bend all the time in addition to flat springs.
Also agree I would lean toward axle replacement since they are relatively inexpensive.
Yoda Keith, I would wait to see what the axle shop tells you. That will ultimately influence your decision.
Re-bending as mentioned is not uncommon. The axle shop may or may not do it on the trailer. Either way, they are probably setup to handle the thin wall tubing. Depending on the shop, they may even be able to make you a complete set of axles in house. There are places around where I am that do such things.
Bridge repair..... I bet this is one of your favorite sites: http://11foot8.com/ Straightening then adding material could be to minimize future deformations due to impacts, or to reinforce the steel as cold bending increases internal stress (strain hardening) and hot bending could change the material yield and tensile strengths (there are probably many other people here with more knowledge on material properties than I have).
Joseph
Tow Vehicle: 2024 GMC K3500 Denali Ultimate Diesel
Coach: 303RLS Delivered March 5, 2021
South of Houston Texas
Folks that do this for a living should know how to manage these axles. Also when thinking about concentrations on the axle, this fellows porta power has a larger footprint than the spring perch on the axle. But these can be dimpled if not handled properly. The fellow in the video not only straightens a bent axle but then performs a four wheel alignment on the rig.
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