UPDATE BELOW in GREEN (4/23/19):
Original Post:
The trailer I recently bought was equipped with the Timbren 3500lb Axle-less suspension. I outfitted it with 33" off-road tires and experienced a catastrophic failure of the hub that damaged the spindle beyond repair. This occurred within 50 miles of putting the new wheels on. I had driven the trailer nearly 500 miles home on it's stock 27" road wheels/tires and experienced zero issues. The bearings rolled smooth and the grease was a bluish color. I pulled the one still-working wheel off yesterday and noticed that the grease is a grey color with a silvery sheen. Pulled the bearings and they are clearly scouring. So, the other hub is failing too.
Here's where it gets interesting and I think people would benefit from this research. Timbren offers TWO different 3500lb 4" drop axle-less options. The one I have is evidently designed for road tires and travel. It's noticeable in that it has a 4 bolt brake plate and uses a 2" square crossmember to connect the sides. It also uses a 5x4.5 hub. The other option is their HD which uses a heavier spindle and a 5 bolt brake plate with 2x3" crossmember and uses a heavier 6x5.5 hub. eTrailer and a couple manufacturers I spoke with say that the HD is the version to go with for off-road travel and heavier tires. They have said that the other version can induce flex when using heavier/larger tires off-road that can lead to catastrophic failure as I experienced. I am now faced with significant corrective costs as I must buy an entirely new HD setup ($800), hubs ($140) and adapters ($140) PLUS have someone cut out the 2" crossmember and replace with a 2x3". I figure this $3500 trailer is about to cost $5500 or more just to correct the issue that the wrong 3500lb axle-less suspension was put on. Additionally, I'll have a perfectly fine 3500lb 4" drop standard setup that I can't use. Hopefully someone needs one for their road going trailer and I can recover a few $$.
Anyway, hope this helps others who may build their own trailers or are looking to convert their standard axle trailers to axle-less save some hard-earned cash and time. I'm literally sick over this as all that money to fix this was intended for upgrades like electrical/solar/linear lifts, etc.
Here are the part #s and descriptions per eTrailer and confirmed by Timbren:
3500lb 4" drop HD (Off-road): https://www.etrailer.com/Trailer-Leaf-Spring-Suspension/Timbren/ASR35HDS02.html
3500lb 4" drop SD (road based): https://www.etrailer.com/Trailer-Axles/Timbren/ASR3500S06.html
4/23/2019:
Ok, so an update and a mea culpa. Timbren part #s are confusing as all heck as they have changed over time and different combos can be created. Turns out I HAVE an "HD" setup, but a version that is 2 years old (part #'s have subsequently changed). The part # is ASR2KHD.... The 2k is the spring rating and the HD is the Heavy Duty acronym in Timbren-speak. It is a "unique" setup: it has an assembly (frame mount and spindle) that are 3500lb rated, but springs that are 2000lb rated. Additionally, it does not have the "wide" axles normally associated for off-road tires. But, the spindles are rated to handle bigger off-road tires. Since I need to run a 1" adapter to convert from 5x4.5 to 5x150, this isn't an issue at all. Given that my Toyota wheels are 60mm offset, the centerline/balancepoint of the wheel is actually directly over the hub flange (which should be ideal) and I have 2" of clearance between the tire and the nearest point of the frame. This should be ideal for my trailer as gross dry weight is shy of 700lbs and my loaded weight will hit 1400lbs on the high side.
Having said this, I think I've finally figured out what actually happened by closely examining the other hub (port side) that didn't fail, but exhibited signs of impending failure.
Starboard hub (critically failed component): When I removed the broken hub from the starboard spindle, I remember that the castle nut was dang near impossible to remove. I had to use a 14" pipe wrench and "lean" on it to get the castle nut loose. At the time, I didn't notice it or give it a 2nd thought. Additionally, I don't recall a washer coming off when I removed the castle nut. It would not make sense to me that the washer (if present) would be destroyed under the high heat like the bearing carriers and bearings themselves.
Port hub (signs of impending failure): I realized that when I removed the non-failed hub (port side), it took considerable force to remove that castle nut as well. Also, after removing the wheel, I noticed that the hub didn't spin freely by hand. It spun smoothly, but didn't "coast" at all. When I pulled down on a lug by hand to initiate a spin, the hub would make a 1/2 rotation and stop....that's all. That would be way too tight IMO. Additionally, there was NO washer present between the castle nut and the outboard bearing. Yesterday evening, I reassembled the hub using new Auto-Zone bearings, added a washer from the bearing kit I purchased and reinstalled only hand-tightening the castle nut to a "firm" feel. The hub exhibited zero lateral play and, when I spun the hub by hand, it would complete a little over 2 full rotations. That seems ideal from all the videos and write-ups I've recently discovered.
My conclusion from all this is that the person who built the trailer over-tightened the pre-load on the castle nut and left out the washers (for whatever reason) which led to binding and incredible heat build up in the hub. The 33" tires likely exacerbated this heat build-up and led to the catastrophic failure. At this point, I can't fault any of the mechanical components (Timbren Axles-less, spindle or Northern Tool hubs). It appears that the hubs were simply "gorilla'd" onto the spindle which would have led to considerable binding, heat build-up and ultimate failure. I also view this as my fault for not checking the pre-load on the bearings when I purchased the trailer. Ignorance is no excuse, I should have tested that.
So, the good news is this: it does NOT appear that I need to buy an entirely new axle-less setup and fab up a new cross-member. I should be able to simply install the replacement spindle and new hubs (once I receive them) following the correct assembly procedures of including the washer between the castle nut/outboard bearing and tightening the castle nut by hand without applying unnecessary additional force that could bind the bearings.
Original Post:
Here's where it gets interesting and I think people would benefit from this research. Timbren offers TWO different 3500lb 4" drop axle-less options. The one I have is evidently designed for road tires and travel. It's noticeable in that it has a 4 bolt brake plate and uses a 2" square crossmember to connect the sides. It also uses a 5x4.5 hub. The other option is their HD which uses a heavier spindle and a 5 bolt brake plate with 2x3" crossmember and uses a heavier 6x5.5 hub. eTrailer and a couple manufacturers I spoke with say that the HD is the version to go with for off-road travel and heavier tires. They have said that the other version can induce flex when using heavier/larger tires off-road that can lead to catastrophic failure as I experienced. I am now faced with significant corrective costs as I must buy an entirely new HD setup ($800), hubs ($140) and adapters ($140) PLUS have someone cut out the 2" crossmember and replace with a 2x3". I figure this $3500 trailer is about to cost $5500 or more just to correct the issue that the wrong 3500lb axle-less suspension was put on. Additionally, I'll have a perfectly fine 3500lb 4" drop standard setup that I can't use. Hopefully someone needs one for their road going trailer and I can recover a few $$.
Anyway, hope this helps others who may build their own trailers or are looking to convert their standard axle trailers to axle-less save some hard-earned cash and time. I'm literally sick over this as all that money to fix this was intended for upgrades like electrical/solar/linear lifts, etc.
Here are the part #s and descriptions per eTrailer and confirmed by Timbren:
3500lb 4" drop HD (Off-road): https://www.etrailer.com/Trailer-Leaf-Spring-Suspension/Timbren/ASR35HDS02.html
3500lb 4" drop SD (road based): https://www.etrailer.com/Trailer-Axles/Timbren/ASR3500S06.html
4/23/2019:
Ok, so an update and a mea culpa. Timbren part #s are confusing as all heck as they have changed over time and different combos can be created. Turns out I HAVE an "HD" setup, but a version that is 2 years old (part #'s have subsequently changed). The part # is ASR2KHD.... The 2k is the spring rating and the HD is the Heavy Duty acronym in Timbren-speak. It is a "unique" setup: it has an assembly (frame mount and spindle) that are 3500lb rated, but springs that are 2000lb rated. Additionally, it does not have the "wide" axles normally associated for off-road tires. But, the spindles are rated to handle bigger off-road tires. Since I need to run a 1" adapter to convert from 5x4.5 to 5x150, this isn't an issue at all. Given that my Toyota wheels are 60mm offset, the centerline/balancepoint of the wheel is actually directly over the hub flange (which should be ideal) and I have 2" of clearance between the tire and the nearest point of the frame. This should be ideal for my trailer as gross dry weight is shy of 700lbs and my loaded weight will hit 1400lbs on the high side.
Having said this, I think I've finally figured out what actually happened by closely examining the other hub (port side) that didn't fail, but exhibited signs of impending failure.
Starboard hub (critically failed component): When I removed the broken hub from the starboard spindle, I remember that the castle nut was dang near impossible to remove. I had to use a 14" pipe wrench and "lean" on it to get the castle nut loose. At the time, I didn't notice it or give it a 2nd thought. Additionally, I don't recall a washer coming off when I removed the castle nut. It would not make sense to me that the washer (if present) would be destroyed under the high heat like the bearing carriers and bearings themselves.
Port hub (signs of impending failure): I realized that when I removed the non-failed hub (port side), it took considerable force to remove that castle nut as well. Also, after removing the wheel, I noticed that the hub didn't spin freely by hand. It spun smoothly, but didn't "coast" at all. When I pulled down on a lug by hand to initiate a spin, the hub would make a 1/2 rotation and stop....that's all. That would be way too tight IMO. Additionally, there was NO washer present between the castle nut and the outboard bearing. Yesterday evening, I reassembled the hub using new Auto-Zone bearings, added a washer from the bearing kit I purchased and reinstalled only hand-tightening the castle nut to a "firm" feel. The hub exhibited zero lateral play and, when I spun the hub by hand, it would complete a little over 2 full rotations. That seems ideal from all the videos and write-ups I've recently discovered.
My conclusion from all this is that the person who built the trailer over-tightened the pre-load on the castle nut and left out the washers (for whatever reason) which led to binding and incredible heat build up in the hub. The 33" tires likely exacerbated this heat build-up and led to the catastrophic failure. At this point, I can't fault any of the mechanical components (Timbren Axles-less, spindle or Northern Tool hubs). It appears that the hubs were simply "gorilla'd" onto the spindle which would have led to considerable binding, heat build-up and ultimate failure. I also view this as my fault for not checking the pre-load on the bearings when I purchased the trailer. Ignorance is no excuse, I should have tested that.
So, the good news is this: it does NOT appear that I need to buy an entirely new axle-less setup and fab up a new cross-member. I should be able to simply install the replacement spindle and new hubs (once I receive them) following the correct assembly procedures of including the washer between the castle nut/outboard bearing and tightening the castle nut by hand without applying unnecessary additional force that could bind the bearings.
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