Spread Axle Bolt Broke - Help!

Glad you got it repaired. As you found, a trailer place not an RV dealer is the most likely place to find the splined bolt. That nut you posted is a locking nut. There are a few different ways to make a locking nut. Most of them are like you posted where the jam something into the threads to stop them from vibrating loose.

None of the camper places around us had the bolt in stock but I found a trailer place (Taylor for any MI people) that had them. I'm not sure of the grade and I was too excited that they had one in stock to remember to ask.

I followed the advice of jacking the trailer up just enough without taking the tires off the ground. My brother inlaw had a driver drill (?) and the bolt came out fairly easy. The threaded end was the part that broke off.. only a couple were left. Things were bent up a bit but I was able to use a c-clamp to pinch it all back together to get the new bolt straight through.

I also followed the advice of tightening the nut and letting it pull the bolt in. The provided nut was indented (? see image) and seemed to be a locking type so I used it instead of a lock nut with the plastic insides (?).

Things look good so hopefully they are and this doesn't happen again. Thanks for everyone's help/advice!

google image

Lowes home centers carry grade 8 hardware, knot sure if they will have he size though. Also try a Napa , Advance, or Auto Zone, they may have somethin that will fit.

If the end of the bolt is missing, measure the total thickness of where the bolt bgoes plus at least 1/2" for the nut and washer. in this application you definitely want a locknut of some sort, usually one with a nylon insert. Bring the old bolt with you to the store to get the right diameter.

Right now the weight of the trailer is supported by the middle hanger and the ones at the other ends of the leaf springs. if you jack up the trailer until the wheels are off the ground, the wheels and axles will be hanging by those bolts and their weight will still have prssure on that bolt. Jack up the trailer to a point hwere the wheels are still on the ground but the weight of the trailer is being held by the jack....youll have to fiddle with the height to find the space where is no weight on hthe bolt.

Jack up the frame until the pressure is relieved from the equalizers (the linkages hooked to the springs on either side of the bolt) Then use a hammer and drift pin or punch to drive the bolt out. Replace with a new splined bolt and drive the head in until it's seated in the hole. Do not turn the bolt head as you will strip the splines. Only turn the nut to tighten or loosen the bolt.

Once you get the tension off of it you will probably have to drive it out with a proper size drift pin. Hopefully, the splines are still holding the bolt from turning. I'll bet that they are. If not, I used to tack them in place. It is an easy fix either way. The splines are there so that the equalizer turns on the bolt and the bolt doesn't turn inside the mount.

Lynnmor wrote:
There should be splines just behind the bolt head. If the bolt turned and rounded the splines, it will always move and won't stay tight. When installing, you must hold the bolt head while tightening the nut. If the hanger is already rounded out, you may be able to flip the bolt to get good engagement on the opposite side.

I doubt very seriously if they would have a splined bolt like you need. You could get a grade 8 bolt in probably the right size, but not a splined bolt like you need! As others have said, go to a trailer parts store that carries suspension parts.

All the RV dealers around here are closed on Sundays. I have a Camping World about 15 minutes away - do you think they would have one?

edit:
I asked around on Facebook and think I found a local hardware store that will have one and be open tomorrow.

subcamper wrote:
Make sure you get the proper grade of bolt (high strength which is grade 8). If you go to a trailer place, you will probably get the correct type. Don't be tempted to go to a Home Depot and use a bolt that fits, it will not be strong enough.

Steve

THIS! If you are not sure what to ask for, take the head of the old one with you. A good hardware or trailer place should have the correct bolt.

Make sure you get the proper grade of bolt (high strength which is grade 8). If you go to a trailer place, you will probably get the correct type. Don't be tempted to go to a Home Depot and use a bolt that fits, it will not be strong enough.

Steve

Good advice above. Most folks would have never caught the problem until they had a major failure. Good job. The nice part is that it is an easy fix and any local trailer supply should have the correct splined) bolt.