Drop axle vs torsion axle - lowering a trailer

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Drop axle vs torsion axle - lowering a trailer

Postby Noreast » Thu Jun 01, 2017 12:06 pm

Hey I'm just looking for some opinions/thoughts.

I'd like to tow my trailer behind a pretty low car. It's like 55" tall and has 6" of chassis clearance, and I might lower it more. want my trailer to look nice and proportional hitched to it. I'm not too concerned about ground clearance. I'd probably raise my rear cabinets so they're still a good height while ur standing

There's plenty of info on the basic axle-over-spring swap, but I'd like more than the ~2in of drop it gives you.

I don't see drop axles discussed much here but this seems like the easiest/cheapest option. Seems a lot of vintage trailers have them. I can get a custom width 5" drop 3500lb one for less than $200 ... But my trailers probably sub 1500lb. Would that be bad? They don't do drop 2500 pounders for some reason.. Aside from being heavier I figure it should be fine since it's all unsprung weight and the trailer is sprung for its size/weight???

A torsion unit isn't that much more $ though...plus you get independent suspension..but it adds a fair bit of complication to the mounting process so I'm not too keen.

lastly - torsion stub axles. I like these a lot. Not an option for me. But withba custom frame you could get the deck a few inches off the ground without a full-width axle underneath. Image the possibilities for for a standie! or any a-bit-bigger-than-a-teardrop-but-still-small travel trailers... I
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Re: Drop axle vs torsion axle - lowering a trailer

Postby tony.latham » Thu Jun 01, 2017 3:41 pm

3500lb one for less than $200 ... But my trailers probably sub 1500lb. Would that be bad?


I think it would ride like a WWI tank.

I'm a big fan of torsion axles.

Tony
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Re: Drop axle vs torsion axle - lowering a trailer

Postby working on it » Thu Jun 01, 2017 5:10 pm

tony.latham wrote:
3500lb one for less than $200 ... But my trailers probably sub 1500lb. Would that be bad?


I think it would ride like a WWI tank.

I'm a big fan of torsion axles.

Tony
Depending on the leaf spring type, and length, you could get a light capacity-rated spring set, to use with the 3500 lb (max rating) axle. Just like the torsion axle fans get "de-rated" axles for lighter trailers. In my case, though my leaf spring 3500 lb axle seemed too stout for my needs with a then-1500+ lb trailer, I wanted stronger springs with a higher load rating, for envisioned rugged travel at a heavier weight. I bought a 3000 lb set, and it rode quite well...now at 2000+ lbs weight, it rides even better (I hope to stop the weight increase prior to 3k lbs). You can order leaf springs of many ratings, and they're easy to change out, whereas with torsion axles, you're stuck with the rating you bought. And then there's the Timbren system, that uses interchangeable rubber "springs". You can change the weight rating, but always lower, not to higher rated, since heavier weights may be too much for a smaller rated base equipment.
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Re: Drop axle vs torsion axle - lowering a trailer

Postby tony.latham » Thu Jun 01, 2017 5:28 pm

whereas with torsion axles, you're stuck with the rating you bought.


He's right, but when you order a torsion axle, you order it for the weight of your trailer.

T
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Re: Drop axle vs torsion axle - lowering a trailer

Postby MtnDon » Thu Jun 01, 2017 5:32 pm

Flexiride torsion axles have the arms fitted onto splined shafts. They can be height adjusted.

I'd try to keep the unsprung mass/weight as low as possible. A heavier than needed axle assembly can result in more road shocks or vibrations being transferred to the sprung mass... the trailer body.
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Re: Drop axle vs torsion axle - lowering a trailer

Postby KCStudly » Fri Jun 02, 2017 6:35 am

I went with a heavier axle because I am using larger/heavier wheel and tire assemblies to match my Jeep and I wanted the larger brake and bearings to go with that. Load appropriate leaf springs suited for the mass of the axle a (i.e. Jeep XJ) and shock absorbers should take care of the unsprung weight concerns... we shall see.

But this is about the polar opposite from the OP's stated goals, a lower ride height for a street rig. I vote for a carefully specified torsion axle matched to expected final weight of camper and starting angle (or the splined version).
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Re: Drop axle vs torsion axle - lowering a trailer

Postby aggie79 » Fri Jun 02, 2017 8:15 am

I would be real careful about going too low on trailer clearance.

In addition to static clearance on a flat level roadway, you need to think about approach angle, break-over, and departure angle when moving. The trailer tips up and down (pivots on the axle centerline) when you go over dips, driveways, crests, etc.

My teardrop is/was a "low-rider". It initially had about 10"-11" clearance. I don't take it off-road, but even so it would occasionally drag at the rear. I also have to take the jockey wheel off of the trailer jack or it would drag in the front. Recently I added a Dexter lift kit (2-1/2" spacers) to the torsion axle to gain a little more clearance.
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Re: Drop axle vs torsion axle - lowering a trailer

Postby videographer » Sat Jun 03, 2017 8:52 am

Noreast wrote:Hey I'm just looking for some opinions/thoughts.

I'd like to tow my trailer behind a pretty low car. It's like 55" tall and has 6" of chassis clearance, and I might lower it more. want my trailer to look nice and proportional hitched to it. I'm not too concerned about ground clearance. I'd probably raise my rear cabinets so they're still a good height while ur standing

There's plenty of info on the basic axle-over-spring swap, but I'd like more than the ~2in of drop it gives you.

I don't see drop axles discussed much here but this seems like the easiest/cheapest option. Seems a lot of vintage trailers have them. I can get a custom width 5" drop 3500lb one for less than $200 ... But my trailers probably sub 1500lb. Would that be bad? They don't do drop 2500 pounders for some reason.. Aside from being heavier I figure it should be fine since it's all unsprung weight and the trailer is sprung for its size/weight???

A torsion unit isn't that much more $ though...plus you get independent suspension..but it adds a fair bit of complication to the mounting process so I'm not too keen.

lastly - torsion stub axles. I like these a lot. Not an option for me. But withba custom frame you could get the deck a few inches off the ground without a full-width axle underneath. Image the possibilities for for a standie! or any a-bit-bigger-than-a-teardrop-but-still-small travel trailers... I

I did the stub axle thing, and it's working out well for Campy.

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Re: Drop axle vs torsion axle - lowering a trailer

Postby tony.latham » Sat Jun 03, 2017 9:50 am

In addition to static clearance on a flat level roadway, you need to think about approach angle, break-over, and departure angle when moving.

:thumbsup:

Tony
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Re: Drop axle vs torsion axle - lowering a trailer

Postby working on it » Sat Jun 03, 2017 11:05 am

Noreast wrote:... I can get a custom width 5" drop 3500lb one for less than $200 ...
  • If you can get the "custom" drop axle for <$200, then you're halfway done...assuming you also mean that the spring perches are located under the frame rails, and that you have sufficient clearance for the extra flex that drop axles usually have (but shouldn't be a problem for a 3500 lb axle carrying a much lighter load). And, the 3500 lb rating is a good thing, since you're unlikely to overload it, and extra strength should guarantee some durability, as well.
  • This site: http://www.trailersauce.com/information/trailer-axle-building/building-trailer-axle-overlaystepped/ gives a pretty good run-down of what to look for when buying or making a good drop axle. A lot of the trailers from the old days had drop axles, usually sourced from cars (drop axles on the front suspension, before independent front suspension became the norm), and they were built strong.
  • If you're set (now) on a low-rider trailer, you might want to change the ride height at some future date (for higher or even lower ground clearance), the drop axle would be my choice, because of the ease of alteration/modification/customization, and the readily accessible spare parts that leaf spring axles have, wherever trailers are made or sold. Torsion axles are a custom order piece; I've never seen repair parts for them at trailer parts dealers, or stores like Tractor Supply and Northern Tool, which carry a lot of parts for leaf spring axles.
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  • featuring: 3500 lb Dexter axle w/brakes & HD leaf spring system > riding on General Grabber 27x8.5-14LT tires, LED lighting inside, A/C & heat, AGM battery 12vdc, 110vac from extended run generator onboard or park power, Coleman dual-fuel stove & Northstar lantern
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