Leaf Spring Shackles

[Roy Schmaus]

I just finished repacking wheel bearings and replacing the leaf spring bushings on our little (1986 Bonair 1690) single axle 17' travel trailer.

The shackle kit I bought was supposed to be 3" between bolt centers but I measured them at 2 3/4" and the ones on the trailer are 3 1/4".

Am I being too finicky if I get some 3 1/4" shackles as this trailer is quite low already? Or will the 2 3/4" units only drop the rig by 1/4"? Spring travel might also be an issue here.

[ron buckner]

NO! You need to find those 3 1/4 shackle plates! If you use either shorter or longer shackles it a. wont fit (too short) or b. you'll change the offset and the shackles will actually over-center and lock up against the frame of the trailer. When that happens the the spring tension ties the shackle bolt into a constant preassure situation and makes removing the bolt a REAL problem.
Typically you want the offset dimension of the Spring hanger and the spring eye to angle about 1" behind the spring eye.

[ron buckner]

If You want to raise the trailer. I'd recommend flipping the axle, that is put the axle under the springs. This will generally give you about 4" more heigth (Assumimg your trailer didn't come that way to begin with). This job can be easily done if you already have the rear hangers off, but it's still not simple. Undo the 4 u-bolts holding the axle to the springs and slide the axle out. It is then that you'll notice there are are little square "dogs" welded in place that the center-bolt of the spring rides in. Those "dogs" will now be on the wrong side of the axle. Solution. weld new ones on the axle or drill appropriate sized holes in the axle (not reommended. but done non-the-less.) It can be argfued that drilling a 5/8" hole at the spring mount can substaintially weaken the axle, which is why they don't do it at the factory but there's no proof other than a factory decision that a spot weld doesn't create a simialr compromize.

[Roy Schmaus]

Thanks Ron.

A trip to a local spring and steering outfit and ten bucks got me the 3 1/2" shackle plates which match the old ones and don't have the oblong holes. New bolts, new shackles, new bushings, about forty minutes per side, and everything looks and works OK.

Something is still creaking under there, I suspect the leaf springs but otherwise everything is ok. I replaced the original breakage prone 3 leaf springs with a four leaf set years ago and they may be getting a bit rusty.

Or maybe I just over tightened the mounting bolts.

As to the height I just use a drop hitch on the supercrew 4X4 and take it off and lock it up in the box if the wife wants to go shopping while on a camping trip.

[Eric J]

I put bronze bushings in mine with greasable bolts to lube the bushings with and it has a slight touch of a creek when backing up and flexing one axle, but not much of a creek.

[Roy Schmaus]

Well I broke down and bought and installed new 5 leaf springs since the spring and steering guys told me that they had problems with the 4 leaf's breaking and also my ten year old bill for the four leaf springs that were on the trailer.

This should have been an easy job but one of the shackle bolts was either cross threaded or rusted on and took a good hour of pulling, getting a longer wrench, purple language, and eventually inching the thing off.

After getting everything re-assembled and torquing the last wheel bolt the rain hit. Talk about auspicious timing.

Jumping up and down on the rear bumper did not produce any unusual noises i.e. the creaking is gone. The rig is about 1 1/2" higher probably due to the old springs being a little less arched than when new.

The only du-ooh moment - Asking the shop to cut the first set of shackle bolts to the same length as the old ones and then getting home and realizing they were for the original 3 leaf springs.