Terminology could problematic here, both from my lack of expertise and also different countries have a bad habit of calling the same thing something totally different. So photos might help, I hope they post on the correct order. So this is what in my area of Australia and I think most of the rest of the country, would call a sliding drawbar, tri-axle pig trailer. It's a 1984 model so it's been around the block once or twice. It is a load sharing suspension that has no shackles to fix the non pivoting end and is what I would refer to as a slipper spring, ie it slips along a wear plate. Before I try and badly explain something to the experts, more photos to actually show it. So firstly is this common type suspension that everyone/anyone is familiar with? Secondly as can be seen in the first side on photo, the trailer is pitching forwards slightly (inch and a half gap over front axle, 3 inch gap over rear). There was no obvious damage or flogged out components to see, so first guess simply is, front axle springs are sagged more than rear axle. Obviously best course of action would be full rebuild, but would a simple fix for limited use be, welding in a 3/4 inch (or whatever height is required) steel wear plate in the end housing where the "slipper" spring is contained, therefore raising the front axle spring? Or simply swapping rear axle and front axle springs (assuming front has sagged more than rear to cause issue) The issue with the trailer pitch is that depending on the height of the rear of the truck ringfeeder hitch, when the sliding deawbar slides back it hits the front axle and therefore can't slide back enough. If the trailer was level, drawbar would slide freely with no interference. In case no one is familiar with the sliding drawbar, it's purpose is to allow the trailer to be backed up to a cattle loading ramp. Unlock the sliding drawbar locking pins, then the truck can back directly up to the trailer (sliding doors either end) and cattle can be loaded/unloaded through the trailer onto the truck etc. Had a look at this trailer today with consideration to purchase, depending upon what amount of suspension work is required to level trailer. Apologies in advance if none of this makes much sense, just got home and haven't slept in 40hrs. So bed time now, I'll attempt to explain better if required after any feedback. Thanks
Could only attach 4 photos so here's some more.
I’m no help- i’ve never seen that type of suspension
Thanks 56, although I was hoping to hear, yeah that's common, what do you want to know. Something I forgot to add in my sleep deprived state last night was that the drawbar is also hinged in the horizontal plane. So that the trailer sits on its suspension alone and drawbar angle has no bearing on the trailer ride height/angle.
Probably illustrates things better.
Maybe welding in a wear plate/spacer would be the easiest option. Maybe there is a worn out pivot in the slipper section area of the frame mount? Are new springs available at a reasonable cost?
Going to go into truck part place today to see what I can find out. Being 40 yrs old, concern is I can't get parts. Id'ing the axles is the next problem, tags are unreadable and the chance of the parts guy knowing 40 yr old axles by sight in photos is unlikely.
I think I'd try to measure all the springs deflection with it on jacks before swapping any around, and if looks uniformly flatter at front/more curved at rear my first choice would be swapping front to rear. If the order of deflection is progressive through the three axles, I'd be concerned that a shim stuffed in the front axle wouldn't correct the tilt for long. Mind you, if it's that progressive, swapping front to rear might tip it back further than you need
I knew it had BPW axles (and assumed springs) under it, but ID tags are no longer readable. Truck parts place had ex BPW employe on staff, thinks he can ID from photos to see if parts still available. Just waiting to see what he comes up with.
Just in case it helps someone else in the future. Axles/Springs are BPW (VA series) and are obsolete, parts no longer available. Getting a price on replacing suspension and then see if the seller is willing to negotiate.
Tri axle looks like the first axle empty set up limit contact with the ground til loaded less rubber wear?
Deere500a, would that work with hinged drawbar?
Maybe mount an airbag on top of the spring over the axle on each side of the front axle with a manual valve to inflate when loading so you can slide the drawbar in
Back in the day just about every one of those trailers I saw had a nose down attitude, they were all tippers and owned by people who couldn't reverse a dog trailer. Some were converted from roadtrain dolly's.
It may even with the hinge tongue have enough rear weight to ride on the rear 2 axles looks like the middle axles pretty well center. Take it to a local scale check the three axles empty & return loaded. Looks similar to a bumper pull hinged leaf springs weight transferring down the line