When we purchased our van (second hand) I had a few concerns about the ground clearence. The van was fitted with an overlay axle. I also noticed that the rear spring dumbjacks showed some signs of wear.

The concern with clearence turned out to be fact, a few times in and out of some driveways it would scrape.

I am not keen on underslung axles, (my personal thought). So I decided to have a straight axle made.

While the axle was out , I decided to look into replacing the springs, being that they are about 12 years old. So began the hunt for new springs. While making enquires and looking at springs, prices supplied were around the $140-$150.

So Im looking at the wear on the dumbjacks, decide to ring a friend of mine who is an engineer and ask about the dumbjack wear and the best solution to the problem. While talking to him I mention the price of springs. He tells me that springs are not dear to buy as a lot of them are imported and made in India, and quality a bit iffy. My friend appears to be on the ball with most things, so I thought I would check on this.

Has anyone else heard this??  

I got back in contact with a couple of the companies and asked where are the springs made, neither could tell me, but both said they were imported.

I decided to go shopping further, I located a Spring manufacturer in Sth Aust, and was told again, a lot of springs are imported & India was mentioned.

The quote, from this spring company, over twice the price than what I had been quoted elsewhere. 

I decided to have this company make the springs for me. When they were delivered it is easy to notice the difference between these and the others I had seen.

Have be very pleased with the service from the company. 

The dumbjack repair job: steel plate, 6mm x 65mm x 90mm long. Bent each end of the plate up ( so it would sit flush on both the chassis and on the dumbjack. ) 

Welded this to the chassis, and then refitted the springs. This plate now sits between the spring and the dumbjack, any wear will be on the plate, not the dumbjack.

Tip: If you van or trailer has slipper springs it might be worth while having a look for any wear.  Use a "G" clamp and compress the spring and have look at the dumbjack for signs of wear. 

Daryl

ozjohn wrote:

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In the industry they're refered to as Slipper Springs. About as cheap and nasty as one can get and best suited for 6 X 4 Box trailers.
If I was going to replace them I would have gone for a straight axle with Eye to Eye springs and shock absorbers.
Ozjohn.

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Ozjohn: I'm aware they are referred to as slipper springs. I am referring to the part that is on the chassis.

Cheap and nasty, most likely if you have the imported ones, and these imports also include the eye to eye springs.

I wonder how many caravan and trailer manufacturers are using these cheap imported springs.

I did fit a straight axle. I considered buying quality eye to eye springs. Sure it would have been a better option, but I chose to stay with the original spring style setup, and ones that are not cheap nor imported.

 Daryl

whoops, double posted, sorry all.

blaze wrote:

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never heard them called dumbjacks before, always known them as slipper wear pads, a consumable item with slipper springs
cheers
blaze

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 Have heard them called a few different names, hangers, wear pads, dumbjacks, slipper pads and slipper retainer. 

Would make it easier to have one name, and save confusion. 

One company I spoke to called them hangers, I thought the hanger is what the spring is bolted to.

Guess its like a, car, motor vehicle, automobile, horseless carriage.

Regards

Daryl

In the industry they're refered to as Slipper Springs. About as cheap and nasty as one can get and best suited for 6 X 4 Box trailers.
If I was going to replace them I would have gone for a straight axle with Eye to Eye springs and shock absorbers.
Ozjohn.

ozjohn:

I posted the thread for a number of reasons:

One being about the imported springs, and I question how many vans have these fitted from new.
One concerning wear from slipper springs, there are vans out there that do have slipper springs and the owners may not all be aware that they can, and do wear.
Another was the repair I had done, and hopefully this may be of assistance to someome.

I apologise to you if you are offended by me using another name, other than what you use. I considered it to be of little importance with the manufacturers when they were using different names for the same part. I never considered for a minute, it would become an issue here. 

spida:

Good to hear that someone you dealt with seemed to be on the ball and picked up on the springs and fitted the Aust built ones.
The price you paid sounds a fair price. I paid $360 a pair for the Aust springs (and fitted myself) The cheapies were approx $140 a pair. Ours definately had sagged the spring measured almost 30mm longer than it was meant to be. Being yours is a tandem axle, most likely it has eye to eye springs.
Regards
Daryl

(edit added spida)

The part that is welded to teh chassis for the 'slipper' spring to slide in is called a spring 'Slipper', and in all my years in the engineering business have never heard of the referred to by any other name except as a hanger. But to be correct the hanger is the spring anchor that is welded to the chassis at the opposite end on the spring. (Front end).
OJ

Hiya D&S,
I didn't for one moment set out to critisise or offend you in anyway, and if I have I apologise.
Having spent the majority of my working life in the engineering buisiness including running my own engineering company the name Dumb Jack is unknown to me.
It sound like it could be a U.S. term for what we call a Slipper.
I congratulate you for fitting better quality springs than the imported ones from the Sub Continent, but did question you going with the original Sliiper Spring arrangement when an Eye to Eye set up copuld have been fitted for a few extra dollars. Add the that shock absorbers, and it becomes a pretty good all round suspension
All the best.
Ozjohn.

ALL Good OZJOHN.!!!!!!
 
Regards

Daryl