I was looking through a 1942 to 1946 shop manual for Chev trucks and cars. I found a procedure for replacing a frame rail on a car. They talked about removing the rivets and when installing the new frame rail, using hot rivets of 5/16" diameter. Then they stated an alternate method using bolts. The procedure was to drill the holes out to slightly under 3/8" and use a GM bolt of 3/8" diameter to bolt it together. This way the holes are completely filled and there are no "undue shear forces" created on the bolts. They gave the part number for the bolts and described them as "hardened".

Over the road trucks are now put together with Huck bolts. This is the bolt we use to do frame repairs because a Huck bolt puller that pulls 5/8" is over $40k.
http://www.imperialinc.com/items.asp?item=0192380 They are also made in 3/8 which are suitable for light truck frames.

What is a Huck bolt? I want to learn about this.

Try this Fred:
http://www.duncanbolt.com/suppliers/huck/huck.asp
http://www.alcoa.com/global/en/products/product.asp?prod_id=806
http://www.kingfastener.com/huck.html
http://www.hucktoolrepair.com/
DG

Huck bolts, or Huck rivets as they are known in aircraft, are nothing more than fancy pop rivets. And trust me, after having years of experience installing them in field repairs when I was in the Air Force I wouldn't give you a nickel for a ton of them.

They are VERY effective in a production environment where equipment is properly adjusted and the environment is controlled but a one-off replacement is hit-or-miss and you better have industrial strength equipment if you plan on pulling any 3/8" diameter blind fastener.

Just use a bolt w/lock washer to replace any rivets you remove. If you plan to work your vehicle to death use a Grade-8, otherwise any quality bolt will work.

Just imagine the amount of force it would take to shear a bolt that big... you would tear the thing through the frame before it would fail.

Czechman, I think you are confusing Huck bolts with blind Hucks. Blind Hucks are a structural grade pull rivets. We use a Monobolts which is like a blind Huck and is pulled like a pop rivet. We use them with sheet and post aluminum where we can't get to it with a buck rivet. A Huck bolt is a completely different animal. I'm not sure that they would be used anywhere on an airframe. This is a link to Huck bolts. http://www.alcoa.com/fastening_systems/commercial/catalog/pdf/huck/en/C50L.pdf I have Huck guns to pull up to 3/8 Huck bolts which is sufficient to fasten the bottom rail to the cross members. All truck frames are assembled with 5/8 Huck bolts these days. Next time you are near a tractor-trailer, look at the frame. They are assembled with Huck bolts. An industry accepted replacement for as Huck bolt is a flange bolt such as this http://www.imperialinc.com/items.asp?item=0192380 Up until about 1995 trucks were assembled with these. They are available in 3/8" and make a much stronger repair than bolts and washers.

All I know about rivets, comes from watching bugs bunny.
When I first got my old Pontiac, I was amazed to see the frame riveted together. Now, I pay attention, and am amazed at the number of old bridges and machinery around me with rivets.
I would think that any bolt, that has an unthreaded shoulder where it passes through the frame, would be fine. But boy, hot riveting would be more fun.

Correct, you are! It's only been 40 years since I was around an aluminum airframe... you'd think I'd remember every detail