Tire & Axle Question #2

Tnx all!
:)

dcmac214 wrote:
:@
(Haven't asked at a 'reputable' dealer yet.)

40' toy hauler, three axles...can I replace the three axles with a single heavier dually-tired axle? There appears to be plenty of room underneath.
Anyone ever do it?
Agree it may look kinda strange with dually tires where you'd expect to see three in line but looks aren't a prime consideration for me.

With a heavy enough axle it could be done, but why? The reason the trailer has three axles is because the frame isn't strong enough for one axle. The load needs to be spread out. If I wanted to convert a triple axle trailer, I would reinforce the frame under the axle area and put heavier tandem axles with an equalizer. They won't scuff tires as bad.

JJBIRISH wrote:

Dog Folks wrote:
When backing up with more than one axle, one axle has to literally "scrub" or slide on the roadway to make the turn. If you haven't seen it have someone else back up a dual axle trailer in a tight turn and watch the tires on the "inside" of the radius. One tire will stop and scrub or may actually rotate in the opposite direction.

I am not an engineer by any means, but with the tires side by side in a dual configuration, on one axle, I wonder if they could "scrub" enough to make a tight turn.

A dual tire on one axle is a very interesting idea, but I also have to wonder why no production manufacturer has tried it.

Keep us posted on what you find so that we all can learn.

Newmar has built 5 ers with tandem axles with duel tires on them back in the late 90’s…

Yep, they did. My son and I looked at one years ago, but decided it was too big and too heavy. Nice trailer, though!

Dog Folks wrote:
I am not an engineer by any means, but with the tires side by side in a dual configuration, on one axle, I wonder if they could "scrub" enough to make a tight turn.

A dual tire on one axle is a very interesting idea, but I also have to wonder why no production manufacturer has tried it.

FYI, look at equipment trailers that haul backhoes, cranes and such. Most have dual axles with dual tires, so 8 tires in total, or triple axles with 12 tires in total. Based on the max capacity of the tires, you add tires as needed to carry the load.

RVs are not as heavy as the loads carried by an equipment trailer so no need for dually axles, probably why not common in the RV industry. But not uncommon for trailers in general.

I would not do it as the load of the trailer is supported at 6 points and you will be taking it down to 2 points with the single axle. I would not expect the structural framing of the trailer to be able to take the greatly increased stress loading.

Somehow I would be more inclined to trust the engineer at the factory who designed the trailer for safety and durability and stay with it in its current configuration of go buy a new trailer.

Dog Folks wrote:

JJBIRISH wrote:

Dog Folks wrote:
When backing up with more than one axle, one axle has to literally "scrub" or slide on the roadway to make the turn. If you haven't seen it have someone else back up a dual axle trailer in a tight turn and watch the tires on the "inside" of the radius. One tire will stop and scrub or may actually rotate in the opposite direction.

I am not an engineer by any means, but with the tires side by side in a dual configuration, on one axle, I wonder if they could "scrub" enough to make a tight turn.

A dual tire on one axle is a very interesting idea, but I also have to wonder why no production manufacturer has tried it.

Keep us posted on what you find so that we all can learn.

Newmar has built 5 ers with tandem axles with duel tires on them back in the late 90’s…

Thanks for posting. In all my years of regular camping,(34) and now 7 years of full timing, I have never seen one.

I found a discussion on a different forum, and everyone that owned them, loved them.

You never know what you will learn on this site. Thanks again.

And must are/were towed with class 7 or 8 trucks.

Chris

JJBIRISH wrote:

Dog Folks wrote:
When backing up with more than one axle, one axle has to literally "scrub" or slide on the roadway to make the turn. If you haven't seen it have someone else back up a dual axle trailer in a tight turn and watch the tires on the "inside" of the radius. One tire will stop and scrub or may actually rotate in the opposite direction.

I am not an engineer by any means, but with the tires side by side in a dual configuration, on one axle, I wonder if they could "scrub" enough to make a tight turn.

A dual tire on one axle is a very interesting idea, but I also have to wonder why no production manufacturer has tried it.

Keep us posted on what you find so that we all can learn.

Newmar has built 5 ers with tandem axles with duel tires on them back in the late 90’s…

Thanks for posting. In all my years of regular camping,(34) and now 7 years of full timing, I have never seen one.

I found a discussion on a different forum, and everyone that owned them, loved them.

You never know what you will learn on this site. Thanks again.

And you will need a single set of brick truck springs to support all the weight on two springs. It will ride like do-do!

Chris

dcmac214 wrote:
:@
(Haven't asked at a 'reputable' dealer yet.)

40' toy hauler, three axles...can I replace the three axles with a single heavier dually-tired axle? There appears to be plenty of room underneath.
Anyone ever do it?
Agree it may look kinda strange with dually tires where you'd expect to see three in line but looks aren't a prime consideration for me.

Hope the dealer you ask has a sense of humor.

The trailers frame is not strong enough for one axle of any size. One axle has about 30" between the spring hangers for frame support.

A tandem axle trailer may have 75" length to support the frame.

A tri axle may have 90" of support.

Even if the axle was a dual wheel axle that means the axle would have to have a the capacity of all the axles it replaced.
A 6k tri axle trailer means one huge 18k axle which will pound the trailer to junk.

rhagfo wrote:

Dog Folks wrote:
When backing up with more than one axle, one axle has to literally "scrub" or slide on the roadway to make the turn. If you haven't seen it have someone else back up a dual axle trailer in a tight turn and watch the tires on the "inside" of the radius. One tire will stop and scrub or may actually rotate in the opposite direction.

I am not an engineer by any means, but with the tires side by side in a dual configuration, on one axle, I wonder if they could "scrub" enough to make a tight turn.

A dual tire on one axle is a very interesting idea, but I also have to wonder why no production manufacturer has tried it.

Keep us posted on what you find so that we all can learn.

Well for the amount of time I spend backing into a space, or in very tight turns, it is of little consequence. I live in Oregon, so the pad is always wet, so of little issue! :)

I can agree, but your circumstances are not typical. Some of us live in the sunshine, with 90 degrees entrance to sites and narrow roads.