Fifth wheel rails

Snowman9000 wrote:
It's very hard to locally find high grade carriage bolts, which is what the rails use. I see they are out there on Google, though.

I got mine from McMaster-Carr Supply. Mine were 1/2"-13 x 2 1/2" long, grade 5 zinc plated. McMaster's catalog # is 90185A722, $8.40 for a bag of 10 bolts, or 84 cents each. They're wonderful folks to deal with, highly recommended.

OK after reading all of the posts and talking to others I have to agree that Grade 5 would be a safer bolt to use then a Grade 8. I found a Grade 5 carriage bolt at a local farm supply so all new bolts grade 5.

If the manufacturer, with all of their corporate legal staff looking at potential liability issues, uses Grade 5 then I would use Grade 5. NEW Grade 5, maybe, but why try to second guess the people who get paid to know the product?

I would bet the hitch mfgs. know what they are doing when they use grade 5 bolts..... Grade 8 bolts are stronger but are more brittle than a grade 5. A grade 5 bolt will bend before it breaks, bending will absorb some of the stress and energy. A grade 8 bolt has no give in it, it hold a bit longer but will break, then it is all over. I would leave them alone.....

I had a 5er blown over on the freeway awhile back. It tore the hitch into little pieces and the grade 5 rail bolts bent a little but didn't break.

Sam

Make sure the have a square shoulder and shims to fill any gaps between bed and rail.

Thanks for the comments guys. I checked with a friend in the hard ware business he said the bolts supplied by Reese are grade 5 I'm going to use
grade 8. Happy trails.

I wandered the same thing, didn't see any marking on them. So i figured even if they weren't grade at least they would work for rating of they are supplied for. That said my next upgrade project will be to swap to complete grade 8.

Charlie D. has it right, don't forget the shims. In addition as previously mentioned they are grade 5 carriage bolts. I got mine at a local farm equipment supply store.

All the bolts from rail to bed that I have seen have a square shoulder. You will also need shims where the bed is recessed. I would only use use the ones that Reese sell. You can get them at Reese's web site. Inexpensive and only a few day delivery. Follow TubaPete's suggestion.

I believe Reese sells a kit with the correct bolts, size and grade needed. Somebody will probably tell me I'm wrong but I thought their bolts had serrated shoulders to keep them from turning when you tightened the nuts down. Saves trying to get a wrench into a difficult spot.