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wardy1
25th February 2006, 01:44 PM
I'm looking at camper trailer and keep coming across 'slipper springs'. what soes this mean? And are they a good option for off road? One other question while we talk trailer suspension, which is beter, beam axle, or independent?

feral
25th February 2006, 07:19 PM
Wardy,
Slipper springs are leaf springs. They are the bargain basement of suspensions for caravans & trailers. All they really do is hold the chassis off the road 8O
They are attached to the chassis on the leading/front as a leaf spring would. At the rear though the leafs just go up to a steel plate on the chassis surrounded by a 'U' shaped bracket and the leaf goes through the middle of this 'U'. It just sits there and slips against the plate.
All ok for general road work but go offroad it would soon break up and that would be it.
So really independent suspension works best particularly if you want to take it offroad.

Cheers,
Lyndon.

wardy1
26th February 2006, 11:28 AM
Thanks lyndon. That pretty much confirms what I thought.
Alan

DougLD
13th March 2006, 02:10 AM
Hi All
On our early Aussie Swag Trailer they have slipper springs it is 14 years old has been around the country with the previous owner and around the center last year on some tracks like the Ghan, Boogie hole tracks without any problems I will replace them before the next trip but i think they would be more easily repaired on the side of the road than a broken independent suspension. I did replace the Shocks before the last trip.
Regards
Doug

JDNSW
13th March 2006, 07:29 AM
Doug,
Yes, the durability of suspension depends on how well it is made rather than the type of suspension. Other characteristics such as ride and wheel travel and towing characteristics are easier to control with independent designs, but again, how well it is designed and made have more to do with the results than whether it is independent or not.

"Slipper springs" are almost invariably used in bargain basement trailers, not so much because they are cheapest (I doubt they are), but because they are easiest to design and build a trailer, mainly because they spread the load in transferring it from the axle to the trailer frame. But just because they appear in bargain basement trailers does not mean they cannot be done well, and they often are, as you point out.

ianswalkingthedog
15th March 2006, 03:02 PM
The biggest problem with 'slipper' springs is the need for constant greasing on the slipper part. When dry they require a much greater load on the spring for small movement. This results in poor ride on relatively smooth roads as the slipper fuction is too stiff to move so you feel every little bump.

Dony knock the leaf spring for off road as it has been used very successfully for very many years. A correctly designed leaf spring with independet axles will do a similar job to the coil spring. The problem has always been the beam axle which transfers cross loads onto the other wheel and hence bounce and tramp. An excellent design for a low profile suspension is to have a long leaf spring with military wraps at each end and an independent swing axle across the vehicle. It will suffer from small movement sensitivity due to the interleaf rubbing, but that has almost been designed out these days.

Food for thought.