Question about crossmembers

[LARSEN]

Some of the original rivts on my frame are coming loose. What is the best way to replace them? Grade 8 bolts?

[my67chevytruck]

yes Grade 8 bolts will work. make sure to use lock washers. you may also want to user lock washers and nylock nuts.

[Tx Firefighter]

My background is in aircraft repair originally, so I tend to always use flat washers with nylon locknuts.

In aviation, a lock washer is fronwned upon because they scratch the underlying metal as you tighten them down. This gives a spot for corrosion to begin. Locknuts and flat washers don't do that.

And, a Grade 8 bolt is sufficient to replace any rivet as long as it is properly fitted to the hole and torqued correctly.

[LARSEN]

Thank you for the replies

[CUSTOM/10]

You have a few options but what ever you do the whole must be tight to what ever you put in. So if the hole is oblong you need to drill it out to the next larger size. I believe the original rivets are 11/32. Not a common size. 7/16 is just slightly larger, so that's a good size to go to. You can bolt it, grade 5 is fine the rivets are mild steel but did get hardened some when installed. I have used wheel studs, 7/16 with a short knurled shank, drill the hole and test fit to make sure the knurled part needs to be hammered or pressed in. The nice thing about the wheel studs is they look like a rivet ( from one side ) once there installed.

The best replacement is new rivets. But that's a though job. I've done it and have a box of 7/16 rivets around somewhere. The rivets have to be cut to the proper length, clamped in place, heated Cherry red and pounded with a special tool to form the rivet head. But when done right there very strong and look like original.

Good luck !
Gary