Trailer suspension

codprawn · 17 November 2009, 11:48

This is not about my boat trailer. I have a nice old trailer I was given that I use for collecting firewood - it probably carries about 1.5 tons but of course I would never do that as the brakes aren't working.

The trailer is very low to the ground. I thought the suspension had collapsed as there is no movement at all and it would explain the low ground clearance.

I have been looking at new suspension units but they work out at abour £300 which isn't really worth it.

I was looking under the trailer the other day and I am now wondering if the axle has been put on upside down!!!

The axle is very heavy duty - looks like it's off a road compressor or similar - big round tube. The suspension units are angled UP at about 45 deg - surely they should be angled down? This would explain the lack of ground clearance.

IF this is the case would years of carrying heavy loads like this have damaged the units? It will be a lot of work with an angle grinder to cut off the axle and then turn it around.

It would be wirth it though to increase the height and have suspension that works!!!

jwalker · 17 November 2009, 12:00

Codders, is it the arms which are pointing up or the whole unit? I've seen units sag to the point where the arms no longer angle downwards.

codprawn · 17 November 2009, 12:11

I think I will have to take some pics. Basically the arms go up at a 45deg angle from the rubber hub part.

jwalker · 17 November 2009, 12:17

Could just be shagged Codders. They're often just a square shaft inside a square tube with the shaft at 45° and round section rubbers squeezed into the corners. If seriously worn or corroded the shaft can rotate so the arm angles upward.

9D280 · 17 November 2009, 12:47

Sounds a bit like the suspension units on the T- frame trailer my RIB came on..... One was locked solid horizontally, the other with a slight up angle. Replaced them with new & it was night & day. Ended up I got rid of the trailer as a launching trolley as funds allowed a nice swing beam to replace it - much easier to launch & recover!

My wee 500Kg box trailer also suffered a "freeze" - but with the suspension in the "unloaded" state, 'coz that's how it spent most of it's idle life. The rubber bits Jwalker talks about will go hard eventually.

I got a couple of 750Kg unbraked units with hubs going spare - only 100 miles and two dunkings if you're interested....

codprawn · 17 November 2009, 13:11

Quote:

Originally Posted by 9D280

Sounds a bit like the suspension units on the T- frame trailer my RIB came on..... One was locked solid horizontally, the other with a slight up angle. Replaced them with new & it was night & day. Ended up I got rid of the trailer as a launching trolley as funds allowed a nice swing beam to replace it - much easier to launch & recover!

My wee 500Kg box trailer also suffered a "freeze" - but with the suspension in the "unloaded" state, 'coz that's how it spent most of it's idle life. The rubber bits Jwalker talks about will go hard eventually.

I got a couple of 750Kg unbraked units with hubs going spare - only 100 miles and two dunkings if you're interested....

Nah I need about 2x that weight - thanks anyway.

Why doesn't anyone do unbraked heavy duty units capable of carrying say 1500kgs - there must be plenty of people who need that weight but not on road.

9D280 · 17 November 2009, 13:29

Braked unit without all the gubbins inside?

codprawn · 17 November 2009, 13:57

Quote:

Originally Posted by 9D280

Braked unit without all the gubbins inside?

Yes but you are still paying for the drums etc.

9D280 · 17 November 2009, 15:09

A lot of them the drums are integral to the hubs.

It's the mass production thing again. For the number that don't need brakes at that weight it ends up more expensive to make unbraked ones for the volume they'll (not) sell!