Trailer hitch bolts

[Bonnewagon]

I just removed a hitch from a Jeep with great difficulty. The grade 10.9 bolts were eroded away to nothingness since they are right in the rear wheel well splash zone. Winter salt got in and just wasted the bolts as well as the hitch. I have a new CURT hitch coming. I know I should use 10.9 or grade 8 bolts for strength but I don't trust them to survive the rust. I thought maybe stainless steel bolts would be the answer. I know they are not as strong but at least they will not rust away. The class 3 hitch is rated for 5000lbs with 500lbs tongue weight but my load is barely 1000lbs and a 100lb tongue weight or 1/5th the capacity. Should I be alright or does stainless come in grade 8 or 10.9?

 

[melloelky]

I hear you on the corrosion,i'm in new england.I'd run new 10.9 or the grade 8 and run it till the hitch falls off again.Run of the mill hardware store stainless is a grade two at best.sure,it's pretty but .it's not good for all things.if you want to go that route contact totally stainless,they carry high strength stainless suited for suspension/factor of safety situations.fyi stainless that strong & that size isn't cheap at all.

 

[pagrunt]

ARP could be a source for strong stainless metric or inch hardware.

 

[Bonnewagon]

I was looking at the Allen Fasteners site which has a lot of stainless and ARP stuff. But not high strength stainless. I'll check that site you mentioned.

 

[axisg]

last hitch on my van pretty much rotted away too. Replaced it all with grade 8 hardware, few stick welds to be sure, and coated it all in fluid film.

 

[Bonnewagon]

YIKES! Totally Stainless has the good stuff. But the 8 fasteners I need would cost as much as the entire hitch cost. Looks like I'll be using 10.9 grade and maybe I can squirt some undercoating all over them. Thanks for that site melloelky. I haven't had sticker shock like that in a while!

 

[axisg]

I know... stainless is great but doesnt seem to have the strength. For towing my boat and trailer ( appx 4000 lbs plus ) I wanted the added security of strong bolts and the insurance of a couple beads of welds to the frame, then coated it all in rust proofing

 

[motorheadmike]

Regularly apply an oil-based rust treatment like Krown or lanolin oil.

 

[UNGN]

Chrome isn't as strong as steel so the more corrosion resistance the put in, the less strength they get,

30 years ago when I was right out of college, My company won a government contract to make CH-47 Chinook helicopter main rotor hubs (what holds the three blades on), that start life as an 800lb 4340 Steel forging and get machined down to a 125lb work of art.. It was raining when the first 800lbs forgings arrived and about a day after sitting in the shop, these $1500 lumps of metal looked like the rustiest Pieces of **** I had ever seen.

That was my first experience with strength not equalling corrosion resistance. I also didn't want to fly on a helicopter that had ever gotten wet, after that.

 

[Bonnewagon]

Yeah, that is why I wanted to try the stainless. I use stainless all the time on the boat and trailer and I have never broken one. But then you have to consider that if you get rear ended what would happen. I'm sure the compression strength would be fine but the shear stress put on the bolts would probably slice them, but on the other hand, they are not as brittle so would bend before failing. I'll see what kind of bolts come with the hitch. If they are grade 2 or even 5 I may still consider the stainless. But the ones the factory used were the 10.9 and I would have piece of mind using them. Unfortunately once the hitch is in place there is no access to the nuts inside the frame rail without dropping the entire rear bumper. Best I can do is slobber anti-seize all over them on the way in.