Single Axle Limitations?

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Tomfoolery
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Re: Single Axle Limitations?

Post by Tomfoolery » Mon Mar 29, 2021 8:34 am

Good catch.

And if the DOT code is only 3 digits, run don't walk to the nearest tire store. :wink:
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Re: Single Axle Limitations?

Post by Inquisitor » Thu Apr 01, 2021 12:54 pm

My tires came original on the 2007 trailer... so way over on age. Checked with my brother-in-law. Being a professional fisherman and putting almost as many miles on his trailer as his truck, I figure he knows what he's talking about. Said hands down... Goodyear Endurance. Got ST225/75R15, E-Loading = 2830 lbs
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Re: Single Axle Limitations?

Post by Inquisitor » Fri Apr 02, 2021 6:27 pm

Got my tires put on today. The factory had not previously balanced them. And the place installing said, there SOP was to not balance them if they weren't before... unless the customer asks. Seemed like a no-brainer to me... I asked.

Is it not normal to balance trailer tires? hull, the trailer will be doing the same 70 mph as the truck. :D
Just because I can't feel it, doesn't mean I want my Mods being vibration tested for 8 hours. :|
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Re: Single Axle Limitations?

Post by kmclemore » Fri Apr 02, 2021 10:27 pm

Actually, no, it’s not common practice to balance trailer tires (although I usually do). The reason being that the trailer, if driven properly, doesn’t exceed the maximum speed for the tires, which for most trailer tires is 65 mph... and some are as low as 55. At those speeds balance isn’t that much of an issue, particularly if the trailer is quite heavy.

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Re: Single Axle Limitations?

Post by Be Free » Sat Apr 03, 2021 7:49 am

I've never balanced a trailer tire and it has been over 50 years since I've seen one with wear patterns that indicated a balance problem. During that time most of my trips were less than 50 miles and and under 60 MPH.
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Re: Single Axle Limitations?

Post by Inquisitor » Sat Apr 03, 2021 8:01 am

Be Free wrote:
Sat Apr 03, 2021 7:49 am
I've never balanced a trailer tire and it has been over 50 years since I've seen one with wear patterns that indicated a balance problem. During that time most of my trips were less than 50 miles and and under 60 MPH.
I guess I was more concerned about the vibration it sent into the trailer/boat than the wear on the tires. My old tires were wearing evenly and I certainly wouldn't have replaced them on wear. I doubt I'll every wear a tire out... it'll always be on tire life as described above.

I bought my Mac and at Bill's in Wisconsin and picked it up in the winter in a weather window. That window dang near closed on me as a blizzard had shut down the Interstates, just behind me, coming out of Chicago and followed me all the way down into Kentucky, Tennessee closing the Interstate mere minutes behind me. I'd bet money, I have the fastest Mac in the world. :wink:
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Re: Single Axle Limitations?

Post by Starscream » Sat Apr 03, 2021 8:31 am

I've heard several garages say that they don't normally balance trailer tires. Makes no sense to me.

I just put the trailer back on the ground...and one tire was flat. Valve stem leak. $10 later it was fixed and I have a set of four 2014 ST215\75\14 Goodyear Endurance on order. 8 ply, made in the USA, to replace my 2014 Goodyear Marathons, which were 6 ply and made in China. They still looked great, but 7 years is 7 years. I'll keep the spare Marathon tire even though it's a 2014, it has only been used once, so I'll take that risk. And yes, I'll be specifying balancing!

I just brought the boat in this morning for a motor maintenance: impeller, plugs, etc, and I tested the trailer brakes by manually activating the controller to max, without using the truck brakes. They stopped the whole rig, but not with a ton of stopping power, much more gradual than urgent. Anyone know if that is normal?

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Re: Single Axle Limitations?

Post by 1st Sail » Wed Apr 07, 2021 6:16 am

Some questions from past experience. My '06 oem steel trainer is still in excellent condition as it has been stored indoors for most of it life. I plan to upgrade to a dual axle this year as we have several long distance trip planned and prefer the redundancy of two axles. I am considering a dual axle from Float On.

That said which is preferred leaf spring or torsion bar.

Do you have to maintain or adjust torsion bar suspension over the life of the trailer to control camber?

Is there an difference in shock absorption between torsion bar and leaf springs to protect the tires? (years' ago I hit a hole on the interstate deep enough to bruise the side wall on my Good Year marathon tire.)

Preference over aluminum vs galvanized steel? (I will be launching almost exclusively in fresh water lakes and reservoirs)
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Re: Single Axle Limitations?

Post by Inquisitor » Wed Apr 07, 2021 6:24 am

1st Sail wrote:
Wed Apr 07, 2021 6:16 am
Some questions from past experience. My '06 oem steel trainer is still in excellent condition as it has been stored indoors for most of it life. I plan to upgrade to a dual axle this year as we have several long distance trip planned and prefer the redundancy of two axles. I am considering a dual axle from Float On.

That said which is preferred leaf spring or torsion bar.

Do you have to maintain or adjust torsion bar suspension over the life of the trailer to control camber?

Is there an difference in shock absorption between torsion bar and leaf springs to protect the tires? (years' ago I hit a hole on the interstate deep enough to bruise the side wall on my Good Year marathon tire.)

Preference over aluminum vs galvanized steel? (I will be launching almost exclusively in fresh water lakes and reservoirs)
I'm certainly no expert, but I can answer part of your questions...
I've never adjusted the torsion bar suspension. And even if you could, It would only adjust height... not camber. The torsion is about the transverse member. I started noticing some camber. I just put a bottle jack in the middle of the cross piece and started lifting. Tires never left the ground, but it arcs the transverse member such that the camber returned to strait. My tires wore evenly.
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Re: Single Axle Limitations?

Post by Tomfoolery » Wed Apr 07, 2021 8:31 am

1st Sail wrote:
Wed Apr 07, 2021 6:16 am
That said which is preferred leaf spring or torsion bar.
My preference would be torsion bar for single axle, and equalized leaf for tandem axles.
1st Sail wrote:
Wed Apr 07, 2021 6:16 am
Is there an difference in shock absorption between torsion bar and leaf springs to protect the tires? (years' ago I hit a hole on the interstate deep enough to bruise the side wall on my Good Year marathon tire.)
Equalized leaf springs might be softer than tandem torsion bar axles on bumps. But I haven't compared the two. When you couple two leaf springs with an equalizer, the effective spring rate at each axle (stiffness) is halved. As the front wheel goes over a bump, both springs are deflected (via the equalizer), making them essentially series coupled. Like putting two identical coil springs together, end to end - the spring rate (stiffness) of the system is half that of a single spring. Dynamics reduces that a little, like hitting bumps at high speed, but the effect is still in play.

Torsion springs are independent, and when you roll over a bump (like a speed bump) with the front wheel, it will take the whole load if the bump is high enough, whereas the equalized leaf springs 'walk' over the bump while still sharing the load. The effect at highway speed is more pronounced, though, but with small deflections, increase in axle load is also small since it's living in the low spring rate zone (torsion axles have highly progressive spring rates, unlike the essentially constant rate of leaf springs).

Another thing that can helpful with equalized leaf springs is that if you need 4000 lb worth of carrying capacity divided between two axles, you can build it with two 3500 lb axles (for instance), for the bigger bearings and wheels/tires, but use 1000 lb springs. I dismantled my 3500 lb (per pair) spring stacks, removed some leaves, and shortened some of the remaining to turn them into lighter, softer springs. Stiff springs don't do anything for you when it's not needed. So between being equalized, and less stiff to start with, my suspension is very soft, yet still perfectly adequate for the load.

To go even softer, you can get cushioned equalizers. I think they're common on horse trailers, for obvious reasons.
1st Sail wrote:
Wed Apr 07, 2021 6:16 am
Preference over aluminum vs galvanized steel? (I will be launching almost exclusively in fresh water lakes and reservoirs)
While aluminium is nice, if it's fresh water only I don't see any reason to spend the money on it. And it's easier to build a trailer out of steel if using leaf springs, as the necessary spring, shackle, and equalizer mounts can be just welded on prior to galvanizing. With torsion axles, I don't think it matters, as they're just through-bolted to the frame rails.
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Re: Single Axle Limitations?

Post by Inquisitor » Wed Apr 07, 2021 9:17 am

Tomfoolery wrote:
Wed Apr 07, 2021 8:31 am
Equalized leaf springs might be softer than tandem torsion bar axles on bumps. But I haven't compared the two. When you couple two leaf springs with an equalizer, the effective spring rate at each axle (stiffness) is halved. As the front wheel goes over a bump, both springs are deflected (via the equalizer), making them essentially series coupled. Like putting two identical coil springs together, end to end - the spring rate (stiffness) of the system is half that of a single spring. Dynamics reduces that a little, like hitting bumps at high speed, but the effect is still in play.

Torsion springs are independent, and when you roll over a bump (like a speed bump) with the front wheel, it will take the whole load if the bump is high enough, whereas the equalized leaf springs 'walk' over the bump while still sharing the load. The effect at highway speed is more pronounced, though, but with small deflections, increase in axle load is also small since it's living in the low spring rate zone (torsion axles have highly progressive spring rates, unlike the essentially constant rate of leaf springs).
Very nice explanation. I never really thought about the coupling. My original gut that independent suspension is ALWAYS better, but I see that is not the case for a trailer. Having a 2008 trailer... would you go so far as to ditch the existing torsion and get leaf?
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Re: Single Axle Limitations?

Post by Tomfoolery » Wed Apr 07, 2021 12:17 pm

Inquisitor wrote:
Wed Apr 07, 2021 9:17 am
I never really thought about the coupling. My original gut that independent suspension is ALWAYS better, but I see that is not the case for a trailer.
If you eliminate the equalizer, you'd have essentially the same thing as a pair of torsion spring axles, but with a fixed spring rate (increase in force is directly proportional to increase in deflection). But torsion axles have the advantage of having a progressive spring rate, so they can be 'soft' for small deflections and light loads (empty trailer), but stiffer for large ones. Just imagine squishing a rubber ball by applying force - the further you squish it, the more cross section there is, and the stiffer it gets. The round rods inside that tube do the same thing.

Leaf springs just bend, but don't change their profile or cross section. So twice the deflection takes twice the force, rather than four times the force (that 'four times' being a made up number). Unless you have leaves in the stack that don't contact the one above until some deflection amount, like 'helper' springs and progressive rate leaf springs. But I digress. :|

Image
Inquisitor wrote:
Wed Apr 07, 2021 9:17 am
Having a 2008 trailer... would you go so far as to ditch the existing torsion and get leaf?
Not a chance. Soft when empty, yet soft enough when loaded. I think those torsion axles are great for single axle applications especially. 8)
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Re: Single Axle Limitations?

Post by March » Wed Apr 07, 2021 3:46 pm

I had been using the original single axle steel trailer for 14 years--from Iowa to Florida and back (twice) and to Lake superior, many times. Had two blowouts over the years--each time, it was without major complications--we just pulled to the side, swapped the wheel, proceeded without a spare and bought a new tire in the closest city, the following day.The trailer didn't sway to pull us off the road, so it was unpleasant, but entirely manageable.

Like many other people on this forum, I added a second axle three years ago--just in case (I had purchased an aluminum trailer that was out of commission for years, owing to the infamous MacBump) Anyway... last year, as we were returning from Lake Superior, the ball bearing to one of the wheels went bad and we found ourselves stranded 150 miles away from home--the two axles notwithstanding. We couldn't do anything except abandon ship, find an axle shop and had the whole axle replaced since the added second axle was set incorrectly and was bound to fail--they said. I had been checking the bearing buddies every 150 miles or so and there had been no signs that the axle would fail. Maybe it was an overkill and I could have changed only that portion of the wheel with the bad bearing myself, had I been at home.

But of course, the trailer was not going to fail "at home". And if I had been "at home," the boat would have been totalled by the Derecho which landed promptly the very next day. Dumb luck and I am counting my blessings

Those axle people took the shortest and more profitable route and changed everything--at least, they did it right. I could see the way the second axle had been added in the wrong place, so this is no bullshit.

The second axle makes driving much easier though.

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Re: Single Axle Limitations?

Post by Be Free » Thu Apr 08, 2021 9:26 am

Tom,
I believe that is the most concise and accurate description and comparison of torsion vs leaf springs I've ever read. Bravo!

I really like having an aluminum trailer but mine sees a lot more salt water than Inquistor's does. If I had a working steel trailer I don't think I'd replace it but I'd sure be saving up for an aluminum one for when the steel one gave up the ghost.
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Re: Single Axle Limitations?

Post by Inquisitor » Sat Apr 10, 2021 5:06 am

Re-reading this thread to make sure I hadn't missed something I needed to know for my next long haul... I did find something. Speed I've never really taken it easy... just because a trailer is behind me. If the Interstate has a 70 mph speed limit, I'm doing 70ish. :wink:
Then Kevin's gave me pause with 60 or even 55 being a possible speed limit for trailer tires. :o I had to check the Internet:

"The Goodyear Endurance is available in Load Ranges D and E to accommodate larger load capacities. It also has a speed rating of N (87 mph)."

Good to go!
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