If I were to go to a hardware store to purchase a replacement bolt, other than size/threads/length is there anything else I should look for? Is there a strength factor?

I hope you understand the question.

Rick

Definitely....

Without going into technical details which I'm not familiar with anyway, bolts are 'graded' for strength.
A fender bolt doesn't have a lot of stresses on it, so it doesn't need to be a high strength fastener.
A suspension fastener WILL have certain stresses put on it that require higher strength specifications.

A Grade 5 bolt\nut\washer is a strong fastener made for certain stresses. A Grade 8 bolt\nut\washer is rated for high strength, like suspension\steering parts.

Here's a couple charts to show you the different 'grades' and the head markings that you'll see on them to help identify them. Remember, that nuts are usually graded along with the bolts, so try to get matched hardware.
http://www.volvospeed.com/Repair/boltgrade.htm

http://www.sizes.com/tools/bolts_SAEtork.htm


You can get some of this type hardware at your home improvement center, but for automotive use, I'd look at the auto parts stores or specialty hardware sources.

Rick,
I just did this about a month ago for the suspension and everything for the subframe. Because I wanted all of the bolts to match, I bought all grade 8 with yellow plating. Even the washers and nuts. Total cost for me, including shipping was only $45 bucks. If you want a list of sizes and number of pieces for each size, I can get that for you. Everything from the tranny crossmember, motormount towers, steering box, control arms, sway bar bolts, idler arm, spindle bolts, etc. etc.

Also, all grade 8's are not created equal. I would not use hardware store grade 8 for suspension bolts.

They should be since the grades indicate the bolts are made to a standard using specific materials. A grade 8 bolt made in China should meet the same specifications as a grade 8 bolt made here in the US. Of course there is fake hardware out there, just like Camaros theres alot of money to be made by adding higher grade markings to low quality bolts and selling them for more money. That caused big problems in the utility industries, especially nuclear plants about 15 years ago.

http://www.sizes.com/tools/bolts_SAEtork.htm

Unless grade 8 bolts were used in the suspension originally it's probably best to stay with the original ratings. Grade 8 bolts are fully hardened and as a result when they fail, they fail britally,ie. just snap without any obvious deformation like bending or stretching. Grade 8 bolts are fine in applications under tension, like holding the subframe to the body, but may not be good in an application like an A- Arm bushing which have side loads.

Good points. Quality control is important.

True, true.... that's why I specified in my reply.
I looked at some of the Grade 8 stuff at Lowes, and although it is labeled as Grade 8 and made for automotive use, the hardware just didn't SEEM right. Maybe because some, just some, of the hardware at Lowes isn't cad plated, and some is. One Grade 8 nut\bolt set was just bare steel, another was cad plated with obvious quality differences.

AutoZone and Advance have automotive bolt\nut\washers. I'd check those first, then the specialty joints like tractor\truck suppliers. Or just buy a complete set from the aftermarket.

Mark,
Nearly all of the suspension bolts are grade 8. The heads of all of the lower control arm bolts as well as those holding the UCA to the frame were marked grade 8. I made sure when doing this that I took all of the bolts down to a REPUTABLE industrial bolt supply. We measured all bolts, check the head markings, made a list and went from there. The only things that aren't grade 8 are the bolts that hold the brake hose brackets on, the sway bar bolts, and a few others. I made them grade 8 anyway because I wanted a match. Yes grade 8's are brittle under bending stresses, but those bolts do not need to have the malleable properties that a lower grade 5 would have.

As far as the plating goes - STAY AWAY FROM HOME DEPOT/LOWE's, ETC. I.E. hardware from local retail hardware stores is not quality plated, it is produce for mass volume. The stuff I got was probably only a few dollars more, and the plating is brilliant yellow and does not rub off when you rub it between your fingers (one place I went, I actually had the stuff come off on my fingers).

Aircraft bolts have the highest quality, are used in race cars.

Rockford bolts are good, made in USA, I got some from a local Peterbuilt truck parts dept.
Caterpillar bolts are good but have a black coating, no cad plating.

The grade 8.2 is not equal to a grade 8 from what I've heard. I think 8.8 is a metric standard.

[ 12-12-2004, 08:20 PM: Message edited by: davidpozzi ]

Great answers and very helpful. I am getting ready to start reassembling the subframe/suspension. I need to bolt these on.

subframe
http://photos.yahoo.com/dukemd66

Rick

Try buying your bolts at a welding supply or a fastener store b/c they will be a good deal cheaper then at an ACE or True Value b/c of the volumes sold AND the quality is fine, imho...

In town here, it's like a dollar vs 3!!! But I gotta buy them during the 7 to 5 week instead of anytime the other two places are open......

pdq67

From all the MANY (EARLY 2nd) Camaros that have been parted out.....dont you have coffee cans and shoe boxes full of.........
Dont really need engine fasteners........
But looking for :
1) Differential U -Bolts and HIGH Nuts
2) Differential Mounting T-bolts
3) Leaf Springs Front Eye Bolts, Nuts, Washers
4) Upper Control Arm Mounting Studs, and SPECIAL "squashed" style Lock Nuts
5) Upper Contols Arm End Washers and Nuts
6) Lower Control Arm Frame Mounting Bolts and Nuts
7) Misc E-brake cable hardware
8) ALL Misc frame related Bolts, Screws, Washers such as Steering Box Mounts, Brake Line Clips, Gas Tank Mounting Bolts
9) Misc Front and Rear BRAKE fasteners
10) Special squashed nuts that hold M.C. to Booster and Booster to Firewall
11) ORIGINAL Stainless Head Bumper Bolts that are NOT dented and can be polished
12) ALL misc sheetmetal mounting bolts

on and on and on................

Chuck Sharin

There are some "kits" now available from aftermarket suppliers such as Rick's, Year one etc. I have seen the body bolt kits, interior kits, engine kits. Have not looked for suspension kits. Typically they are close in have the correct bolt head markings if that is important. They are expensive but you don't have to do the leg work for the proper bolts as they come marked/bagged individually for each application.

Just another suggestion is your time is worth more than your money!

For a really good down-to-earth lesson about fasteners pick up a copy of Carroll Smith's "Nuts, Bolts, Fasteners, and Plumbing." It's a great read.

I too don't like most home superstore fasteners. For suspension and steering linkage I use airframe bolts from Aircraft Spruce. They are Grade 5 but the bolt length can be tailored so that the threads are not in shear. This makes the G5 airframe bolt equal to the stock G8 without calculating in the additional stress concentrations caused by the threads being in shear on the stock G8. Combined with an AN self-locking nut and washer a G5 1/2"-20 bolt in double shear will support 25,000 lbs.

Your local GM dealer will also have suspension bolts. They don't deal with the junky stuff.

i would definitely go to industrial supply you will save lots of money over lowes etc you can buy boxes for the price of a few bolts but the best bolts are NAS bolts (aircraft stuff) but they are very pricey

There used to be a "tough as nails", Grade-8 or maybe even Grade-12 bolt out there called "Supertanium Alloy" that was aircraft grade.

I used some on the old Jackson "wire" tamper I operated on the RR when I was a kid!

Never forgot how "pretty" they were!!

I had several of them in my toolbox for years but I don't know if I even have a little one left after all this time?

pdq67