The Stovebolt Site Forums The Shop Area Driveline bolt sizes

Not sure where this question belongs, but...
I'm getting ready to install the steering box and brake/clutch pedal assembly, and need to buy new nuts and bolts. I'm planing on using grade 8, but I don't know what sizes to get. I have the assembly manual, which shows the nuts and bolts, but only GM part numbers, not sizes!
Is there any list or code showing size compared to part number? These things are a bit too heavy to hold in place and try to measure!
Tim

what year and model are you working on?

I'm working on a 1953 1 ton (3800).
I started this project in 2002, picked it up again in 2005, and am now going at it again. The problem is that I essentially dismantled it in 2002, and now I am faced with a pile of parts and a bucket of bolts, and no memory of what went with what!
Tim

Sort through your bolts 'til you find one that looks close, try it in the hole and note if it fits. Most bolts will be std. sizes, 1/4-20, 5/16-18, 3/8-16, etc. for bolts with nuts, or could be the matching NF sizes of 28, 24 pitches. Get yourself a chart of NC and NF thread sizes to hang on your wall. In general, NC bolts are used in cast iron and Al, NF bolts are used in steel.

Ed

If the bolts are threading into cast iron, such as the steering box, a grade 8 bolt might not be a good idea. Tightening it enough to get the required "stretch" to keep it from loosening might overstress the threads in the box. Grade 5 might be a better choice. Nut and bolt connections are a different story, as long as the grade of the nut matches the bolt.
Jerry

Bluesman: Solid advice from Ed and Jerry: As a general answer for your or anyone's rebuild and the "bucket of bolts" syndrome. We have all done that. The proper way next time is to label the bolts somehow or screw them back in the threads they came out of. No need for grade 8 on our trucks. Grade 5 is very sufficient.

Thanks all for the advice. I have been going through my bolts, and finding ones that work as I go along. I have found some bolts left in the frame from when I took things apart, which amazes me that I had so much foresight! As far as grade 8 vs grade 5, I have only been using grade 8 when bolting through the frame to attach things like steering gear and pedal cluster. I figure stronger is better for those things. Grade five is being used when it bolts into something, like the manifolds. I have been taking my old rusty bolts/nuts, etc and running them through my rock tumbler, then washing them and spraying with PB Blaster, so that at least they are in good enough shape to thread.
Tim

Bolts are inexpensive enough, that for me, the labor to clean them is not worth it, plus, nice, new plated bolts really look nice.

Ed

Good point Ed. I try to reuse them. It's therapy and I get a satisfaction from it. Weird but true. Would not recommend rock tumbler. Seems like it would knock the crest off the threads. I wire wheel or low pressure blast bunches of hardware in a frying basket I got at Goodwill. Shake and blast. It takes 10 seconds. If they are greasy, I shake them in a container of gas with a lid, first.
Then chase and paint.

Add me to the bartamos Weirdo Old Bolt Cleaning Club.
I use a bench grinder mounted on a pedestal with a wire wheel on it. I side benefit with the bench grinder/wire wheel is that you will always have a continuous supply of extra fasteners. Unfortunately they will be scattered throughout your shop from this high velocity small parts distributor.

...and your fingers will get the skin worn off. That's why I am trying to perfect the Fry Basket blaster technique.

I can't believe how a bolt can hide after shot from the wire wheel.
Don't EVER operate a wire wheel without goggles.

As far as damage to threads in my tumbler, I run 200 grit silicon carbide for about three hours. No damage to threads, my tumbler rotates about 20 rpm, and everything comes out clean and pretty. I wouldn't use this for bolts that would especially show, like on the engine, but for mounting parts to the frame it does great.
Tim

I use various sizes of rubber and plastic tubing to hold bolts that I want to clean in my blasting cabinet. Also use old bolts and threaded rod to hold nuts for cleaning. This allows me to use many original fasteners. To do the nuts, I screw an old nut onto the threaded rod, leaving a couple of threads exposed. The,, I screw the good nut onto those threads and lock the nuts together and clean the nut as much as possible, flip it and clean the rest.

Joe D.