ATF: Cyclone - Axle Spacing

[scottyb]

1st let me say that I love my 4100. I only have one pet peave and that is the spacing of the axles. 1st of all, they are too close together. They don't even match the scallops on the fenders. 2nd, they are not symetrical. The rear axle is significantly closer to the center axle, than the front to center. I have been on Dexter's web site and reviewed their specifications on axle spacing. Standard spacing is 33" and optional spacing is 35". I simply don't understand why they would use the standard spacing when the tires are so close together and do not match the spacing of the fenders. There should be no issue in tire selection for a triple axle trailer. I have towed several triple axle trailers, both boat and flatbed gooseneck, and the axles are always spaced further apart. I looked at a Voltage Toy Hauler and the axles on it must have at least 4" of clearance between the tires.

I brought this up with my dealer, especially the lack of symetry, and after inspecting it, he said they were in spec. Interesting that they are also the dealer for the Voltage. I am attaching a picture of the Voltage and it's axle spacing. The 2nd photo is my 4100 and you can clearly see that the rear is closer and that the spacing does not match the fenders.

 

[danemayer]

Scotty,

When you changed your tires, did you compare the outer diameter of the Michelins to the original tires? If you got the Michelin LT235/85R16/E, they are 32" which would not leave much space.

 

[oscar]

OK, you made me take a flashlight and go out there. Yes, the rear and middle axle spacing is less than the middle and front, by about a half inch I would say. And yes, it appears to be less than the Voltage picture you posted. It does not appear as close as the Cyclone picture you posted, although that may be the picture. If I WAG (a few beers in there as a correction factor) I'd say 2.5" between rear and middle and 3" between middle and front.

I can take a measuring device out there in the morning after some coffee and confirm that.

All that said, I don't see where this is a serious issue.....

 

[scottyb]

Yes, the Michellins are larger and I knew that going into it. My problem is, even with the OEM tires, the axle spacing was too close and doesn't fit the industry standard, not to mention the lack of symetry. If I had chosen a Voltage, it wouldn't have made a difference if I put 235 85R 16. If you look at the axles on the Voltage, as well as most 3 axle trailers, the spacing is not an issue. Even if you think the 33" spacing is acceptable for 16" wheels, what about the symetry issue. The scallops for the fenders are spaced for 35" center to center. Look, all I am saying is that it appears that HL didn't take into account, the difference in axle spacing when they switched from 15" wheels to 16" wheels. Obviously, Dutchmen and Voltage did.

Oscar, the reason my tires look closer than yours is because i replaced the Towmax with 235 85 R 16 Michellins. That should not have mattered. Most of them look like the photo of the Voltage. Look at the scallops on your fenders and look at other 3 axle trailers.

 

[Vtxkid]

I know I don't have a triple axle but I can say that with our 3010 Cyclone, I also noticed that the scallops don' t quite match up with a couple of the wheels which has bugged me from the day we purchased it!...

Sent from my DROID BIONIC

 

[oscar]

Slides are out right now, so it's hard to see. I will take a look tomorrow when I retract. Thanks.....something to bother me I didn't even know about.....

 

[porthole]

Not making an excuse for the symmetry issue.But the trailer frames, with axles are delivered to Heartland assembled.

The trailer sides with the "scallops" are set on top of the frame. So it is not like the axles are set to match the openings.

That said, you would think with CAD, robotic assembly and welding, that there would be no reason to think the spacing and symmetry would not be perfect.

 

[oscar]

Agree with Porthole. That said, I went out and looked this morning and the rear axle is distinctly closer, by more than an inch, to the middle than the front is to the middle. I would hope there is an engineering reason for this, other than trying to get rid of a pile of leftover shorter springs......

And yes, it does look goofy with the wheel wells...

 

[danemayer]

Agree with Porthole. That said, I went out and looked this morning and the rear axle is distinctly closer, by more than an inch, to the middle than the front is to the middle. I would hope there is an engineering reason for this, other than trying to get rid of a pile of leftover shorter springs......

And yes, it does look goofy with the wheel wells...

Take another look at the suspension. Look at what the axles are attached to. Look at what that assembly is attached to. I think you'll see that the equalizers and shackles allow for a bit of independent movement of the axles. So looking at the spacing on the ground at any given moment doesn't mean much.

If you want to find out whether the spacing is correct, start by measuring the hangar bracket spacing, center to center. The brackets are welded to the frame and can't move. If you have 33" axle spacing, for Dexter suspension the hangar spacing should be 29.5". It may be a little different for Lippert suspension.

You might also take a look at the spring packs where the axles are attached to make sure nothing is broken, loose, or out of position. That might account for uneven spacing.

 

[oscar]

You might also take a look at the spring packs where the axles are attached to make sure nothing is broken, loose, or out of position. That might account for uneven spacing.

On the left AND right side on a brand new trailer the exact same fault....really?

But, for schnitz and giggles I crawled under there.... Mind you I'm on vacation and I am wearing my "nice" clothes" and I don't have a creeper with me.

Everything looked proper, and was in a resting position. Nothing "broken, loose or out of position".

The spacing on the big U brackets welded to the frame from front to back is 29.5/33/29.5 The springs are all 26"

BUT, and that's the BIG BUT, the way the springs are attached to what looks like a Dexter EZ-flex system is different for the rear and front axle than it is for the center axle which brings it back quite a bit. It all looks proper, and it all looks on purpose, but the result is undeniably that the front and rear axle are centered on their hangers, but that the center axle sits closer to the rear than the front.....(and not the rear being closer to the center as I previously thought).

When I get home I will get under there with a creeper and take some pics.

 

[scottyb]

The trailer sides with the "scallops" are set on top of the frame. So it is not like the axles are set to match the openings.

I'm sure this is true. However, the pattern used to cut the scallops is not set up on a 33" C-C. In fact they measures exactly 35" C-C which I think is the proper spacing for 16" wheels and tires. Dan, I measured the hangers and they are exactly 29.5" on F-C and R-C The span on the center leaf is 33" I'm not sure why there is a lack of symetry. I know the axles are allowed to float a little but this condition is constant and not just when making a turn or backing up. I will probably end up having the axles spread out to the 35" spacing and replace the leafs, hangers, a bolts with some upgrade stuff.

 

[oscar]

I think those numbers are consistent with what I posted earlier, with the addition (again) of the fact that the center axle is attached differently resulting in an off center position.

 

[danemayer]

I've discussed axle and hanger spacing previously with Dexter engineering. Dexter told me that the 33" spacing is for 6K axles and the "optional" 35" spacing is for the 7K axles. I don't remember for sure, but I think the EZ-Flex assemblies may also be different.
You should talk to Dexter about whether your current EZ-Flex assemblies would be appropriate for the new spacing.

If you spread the hangers, the shackle position may end up too close to horizontal, which could be a problem. The shackles could flip when lifting the frame, or when hitting a bad bump at highway speed.

 

[oscar]

Dan, if the 33" spacing is for 6K axles, why is the spacing to the front and rear 29.5" ?

 

[danemayer]

33" is the spacing of the axles. 29.5" is the hanger spacing. I've attached the Dexter diagram that shows how it's supposed to be. Look at the table for 33" spacing and the column for 26" springs.

 

[oscar]

Very cool. Now, based on my measurements for the 26" spring I am 1" short on the "B" dimension and 2" short on the "E" dimension, although it appears the chart is for 7K axles, whereas mine are 6K.

I will measure the C dimension, again, after driving straight on a level surface for a little.

BTW, the hanger configuration shown is what I have.

 

[oscar]

Correction I was looking at the optional 35" spacing, whereas the numbers for 33" spacing all jive, except that the "C" dimensions are not the same....

 

[scottyb]

I've discussed axle and hanger spacing previously with Dexter engineering. Dexter told me that the 33" spacing is for 6K axles and the "optional" 35" spacing is for the 7K axles. I don't remember for sure, but I think the EZ-Flex assemblies may also be different.
You should talk to Dexter about whether your current EZ-Flex assemblies would be appropriate for the new spacing.

If you spread the hangers, the shackle position may end up too close to horizontal, which could be a problem. The shackles could flip when lifting the frame, or when hitting a bad bump at highway speed.

If I spread the axles, I will do it with all of the appropriate replacement parts, leaf springs and all.

If you think about it, the OEM 16" tires are 30.8" with a radius of 15.4". That only leaves 2.2" seperation at best. I still maintain that the 33" spacing is meant for 15" tires and wheels. Otherwise, why would the rest of the world use 35"?

 

[TXTiger]

I too replaced my stock TowMax tires with the Michelin 235/85R16. The spacing between my tires now is so close that I can not even use a wheel chick between the tires. The rear tire is closer to the middle tire than the front tire is and the passenger side rear tire is closer to the middle tire than the drivers side tire! rear tire. Had an allignment shop measure the spacing and take pictures and send them to Lippert. Lippert said all was fine? According to them the axel needs some flex room for making turns and backing up.

 

[oscar]

The spacing between my tires now is so close that I can not even use awheel chick between the tires.

That sounds too close, then again as long as they don't touch.....