axle specifications question

[mike_c]

I have some newbie questions about axle specifications. I've been planning to use a Dexter Torflex axle but I spoke with Grant at LilBear this afternoon and he said he *might* have an axle in inventory that would work for me, but I still have to nail down the specifications.

I'm building a nominally 5 x 10 teardrop using Kevin Hauser's Kuffel Creek Comet plans as a starting point. I've widened the frame somewhat from Hauser's specs, so the chassis (without tongue) is 115" x 56". With 0.5 inch plywood walls outside the frame that produces 57" trailer width before adding wheels.

Although the plans call for a #9 Dexter axle (1000-2200 lbs capacity), I'm planning to use my teardrop in some fairly rugged off-road applications. I don't really know what sort of weight to expect yet, but I'm assuming the dry weight will be somewhere in the 1000 lb range (more? less?) if I build according to plans. We often camp in remote places for a week or longer, taking lots of supplies, bikes, etc, although the TV is a compact pickup so it can carry stuff too. Nonetheless, the trailer load will always include lots of water, battery, propane, gear, etc on top of the dry weight.

Question 1: Despite the extra carrying capacity of the TV, would it be appropriate to order a heavier axle, i.e. a #10 Dexter (2300-3500 lbs capacity)? Is there a downside to doing this? I assume it would be stiff at lower loading, but is that a problem? I anticipate bouncing along many miles of washboard, and that's the good roads....

Question 2: Reading AT's axle/suspension info, they suggest that rubber torsion axles might NOT be good choices in dusty, washboard environments. They said that in their tests, rubber torsion axles failed when dust got into the works. How likely is this to be a problem? Did AT have this experience because they beat their axles to death, or is premature failure a frequent issue when rubber torsion axles are used in dusty, rough applications? Has anyone here had this experience? (AT didn't like leaf-springs either....)

Question 3: My frame is 56" wide, so that's my outside bracket to outside bracket length, but I'm not sure what to specify for a hubface to hubface length. I'm at a loss to figure out the hub-to-hub distance but Hauser's plans specify a 60" hub-to-hub for his 47" wide frame, so 6.5 inches for each side of the trailer (outside frame to outside hub face). Applying those dimensions to my chassis, I get 56" + 13" = 69". Does that sound correct? I can't find hub dimensions anywhere, so I'm assuming that they should be similar and if those hub-to-hub lengths worked for Kevin Hauser they should simply scale up for my trailer. Is that right?

Grant (if you're reading this), you mentioned in another thread (long ago) that you usually use 71"-72" axles on your 5 ft teardrops. If you have one of those, would it be appropriate on my 56" chassis or is that too wide an axle for that frame? Damn, I wish I'd had this conversation BEFORE doing all that cutting and welding!

Question 4: Hauser's plans call for a 22.5 degree down start angle. It looks like that will yield something close to the ride height I want (~ 16 inches) at light load on either a #9 axle or a #10, using a 15 inch wheel in either case. Does that sound about right (assuming 1000-1200 lb trailer weight)?

OK, I think that's it for now. I'll post pics of the work accomplished so far soon. Not much to see yet but the steel frame though.

Best,
Mike C.

[dh]

I'll tackel 2 of yoru questions. First, I don't put torsion axles on trailers that go off road. Springs and shocks will be better suited. Second, you gotta get your wheels first to determine your hub face to hubface. Measure from hub seat to tire, add you1/2'' wall and the desired clearance from tire to wall and multiply by two.

[mike_c]

I'll tackel 2 of yoru questions. First, I don't put torsion axles on trailers that go off road. Springs and shocks will be better suited. Second, you gotta get your wheels first to determine your hub face to hubface. Measure from hub seat to tire, add you1/2'' wall and the desired clearance from tire to wall and multiply by two.

Well, I'm glad I asked BEFORE buying and installing a torsion axle!

Anyone else feel the same way? I have a welded frame on my back deck and need to put wheels on that sucker somehow so I can get on with the TD build!

Also, if you need to buy the wheels before you can specify the axle length, why does Hauser specify a 60 inch hubface to hubface length without specifying wheels? He does say to use a zero offset wheel, but isn't that standard for trailers anyway? I'm confused!

--Mike C.

[grant whipp]

... Although the plans call for a #9 Dexter axle (1000-2200 lbs capacity), I'm planning to use my teardrop in some fairly rugged off-road applications. I don't really know what sort of weight to expect yet, but I'm assuming the dry weight will be somewhere in the 1000 lb range (more? less?) if I build according to plans. We often camp in remote places for a week or longer, taking lots of supplies, bikes, etc, although the TV is a compact pickup so it can carry stuff too. Nonetheless, the trailer load will always include lots of water, battery, propane, gear, etc on top of the dry weight.

Question 1: Despite the extra carrying capacity of the TV, would it be appropriate to order a heavier axle, i.e. a #10 Dexter (2300-3500 lbs capacity)? Is there a downside to doing this? I assume it would be stiff at lower loading, but is that a problem? I anticipate bouncing along many miles of washboard, and that's the good roads....

Hi, Mike!

Let's get this one out of the way right away ... on a torsion axle (of any brand, do NOT consider a spring rating of much more that 750# over your estimated dry weight (unless you always carry that much gear) ... typically, I only spec 500# over, max. With an over-stiff weight rating, you're going to shake the trailer apart in no time!

Question 2: Reading AT's axle/suspension info, they suggest that rubber torsion axles might NOT be good choices in dusty, washboard environments. They said that in their tests, rubber torsion axles failed when dust got into the works. How likely is this to be a problem? Did AT have this experience because they beat their axles to death, or is premature failure a frequent issue when rubber torsion axles are used in dusty, rough applications? Has anyone here had this experience? (AT didn't like leaf-springs either....)

Sad to say, I don't have any experience with heavy usage of torsion axles in off-road conditions ... I've taken my trailers off-road many, many times, but nothing that could be considered "serious off-loading". That said, I can't see any real problems using torsion axles off road, as long as they are maintained properly. I've been fairly dissatisfied with the products and service (lack thereof) from Dexter in the last several years ... if it were me doing this trailer, I'd seriously consider contacting FlexiRide to see if they could set me up with a 2,000# torsion axle with the adjustable trailing arms.

My good friend Larry Sorensen built a 5'x10' Benroy-styled teardrop specifically for hard & serious off-road trailering, and he used a 3,500# straight axle on 2,000# springs, with shock-absorbers ... it has traveled many, many thousands of miles with nary a problem! I had started to build a 4.5'x8' Benroy-styled teardrop with a Dexter torsion axle to go head-to-head with him and do a real-world comparison, but sadly, the project never got beyond the chassis and walls stage (customers' projects always came first!) ...

Question 3: My frame is 56" wide, so that's my outside bracket to outside bracket length, but I'm not sure what to specify for a hubface to hubface length. I'm at a loss to figure out the hub-to-hub distance but Hauser's plans specify a 60" hub-to-hub for his 47" wide frame, so 6.5 inches for each side of the trailer (outside frame to outside hub face). Applying those dimensions to my chassis, I get 56" + 13" = 69". Does that sound correct? I can't find hub dimensions anywhere, so I'm assuming that they should be similar and if those hub-to-hub lengths worked for Kevin Hauser they should simply scale up for my trailer. Is that right?

That is more-or-less the correct thinking ... as long as you can get your wheels made with your specific offsets to go with the given HF-to-HF measurements. Otherwise, like "dh" said, get your wheels first, then work backwards from there.

Grant (if you're reading this), you mentioned in another thread (long ago) that you usually use 71"-72" axles on your 5 ft teardrops. If you have one of those, would it be appropriate on my 56" chassis or is that too wide an axle for that frame? Damn, I wish I'd had this conversation BEFORE doing all that cutting and welding!

Sorry, I don't have an axle to fit your needs

Question 4: Hauser's plans call for a 22.5 degree down start angle. It looks like that will yield something close to the ride height I want (~ 16 inches) at light load on either a #9 axle or a #10, using a 15 inch wheel in either case. Does that sound about right (assuming 1000-1200 lb trailer weight)?

With 15" wheels, I wouldn't go more that 10º down ... 10º down with the 15" wheels & tires that matched my 4X4 Ranger netted me an 18" ground clearance on the frame, that matched the Ranger's. Of course, if you get the FlexiRide axle, then you can custom-taylor your ride height.

OK, I think that's it for now. I'll post pics of the work accomplished so far soon. Not much to see yet but the steel frame though.

Best,
Mike C.

Don't know if that helped much or not, Mike, but continued Good Luck all the same. I think you'll find that serious off-road trailer folks have many differing opinions (and, strongly held ones, at that) about what does and doesn't work for successful and somewhat trouble-free trailering ... you just have to weigh the options and opinions and choose the ones that sound like they will work best for you. As always, then ...

CHEERS!

Grant

p.s. - in case it wasn't clear from all I said above, personally, I wouldn't hesitate to take a torsion axle off road ... I think the advantages far outweigh any potential disadvantages ... ...!

[aggie79]

Mike,

The following link is to the build by Larry and Diane that Grant referenced:

http://www.outbackteardrop.com/

I don't have any off-roading experience at all other than some oilfield construction work I did 3 decades ago, and I don't think my teardrop has left pavement. I used a #9 Dexter with 10-degree up start angle, 15" wheels, and p235-75R15 tires. This combination netted me 12" of ground clearance with the teardrop loaded. I would imagine that the 10-degree up start angle, like Grant said, would get you the clearance you want.

Good luck and post pictures when you start construction,

Tom

[dh]

He does say to use a zero offset wheel, but isn't that standard for trailers anyway?

For trailer wheels yes, but you don't have to stick to trailer wheels. Mine came off an old Chevy truck.

[mike_c]

What Grant said....

Thanks, Grant-- that answers most of my questions. Now I just have to get wheels on this thing and start the teardrop part. I can't tell you how much I appreciate your taking the time to respond! I'll probably be stopping by LilBear sometime in the near future looking for parts, advice, or just commiseration!

Aggie79 and dh-- thanks for your comments as well. I've never built anything like this and I REALLY appreciate the help! I'm beginning to understand why everyone is so enthusiastic about this forum. That's a sweet chassis, dh. Mine still lacks the tongue, and of course the axle, lights, etc, but it's half-way there! I figured I could always build a cross-braced rectangle until I got the running gear resolved. Shade tree engineering, at it's best (or it's worst).

--Best,
Mike C.

[dh]

Mike, thanks for the compliment on my frame. Please let us know what you finally go with. I've got a Dexter #9 on mine, I went with a 30 down start angle, but am also running lower profile 15''s and have around 13'' of ground clearance with the high profile bracket.