Con

Can anyone please confirm the steering knuckle bolts are both 7/16-20 and 2 inch?

Rebuilding my front suspension and have cleaned everything up, replaced races, bearings and trying to bolt the spindle to steering knuckle. When I took it apart one of the bolts came out easily but the other was completely frozen. It broke in half, required a very BFH and many blows to remove. I've lost half of it so cannot measure. Go figure. I did not disassemble the right side so I could use it to copy. Today I tried to remove the bolts to measure, and again one came out and the other (same one) is frozen. It's the aft bolt and the one that's short.

Everything I can find (Zip, other vendors, and Chassis Restoration Guide by Tripoli) says 2 inch but it's not long enough. Picture attached. A 1/2 inch longer bolt will solve the problem but I'm concerned I may have done something else incorrectly to require the longer bolt.


Any help appreciated. Thanks
Con

Avispa

Had the same problem replacing spindle bolts on my 66. All the vendor catalogs showed 2 1/2 inches for the bolts and they weren't long enough. Finally decided I was going to believe my lying eyes instead of the vendors and bought 3 inch 7/16 fine thread grade 8 bolts. You didn't do anything wrong and 4 years later I still don't know what's up with the vendors for these bolts. Put in the 2 1/2 inchers and get yourself back on the road!

Con

Thank you. I've racked my brain for a couple days. The geometry of the knuckle says it needs to be longer.
It will be a while before I'm on the road but need to move forward.
Appreciate your help

SupremeDeluxe

They are two different lengths, at least on a 63-64. The forward bolt is shorter.

I have a set at work, I can measure them tomorrow if you want. Paragon has the correct bolt kit, I have used it on 2 cars in the past.

Con

Thanks. I did not see the Paragon set which has 2 lengths. I'll get the 2 1/4 in bolts and move on. No need to measure. Appreciate the offer though.
Thanks
Con

Speed Direct

As an FYI to everyone, this holds true for all C2 and C3 steering arms 63-82. The rear bolt boss is thicker than the front boss so a longer bolt is needed in the rear location.

jim lockwood

Trust your measurements and then buy ARP bolts, washers, and nuts from their a la carte catalog. You won't be sorry.

Con

[QUOTE=jim lockwood;1606080084]Trust your measurements and then buy ARP bolts, washers, and nuts from their a la carte catalog. You won't be sorry.[/QUOTE ]

I've read many of your posts Jim, and you are clearly a corvette rock star, so your comment is taken to heart, but ARP, at $5 each, are not inexpensive bolts. These are clearly very important for safety so easy decision. I've been trying to identify other bolts which are equally important for safety. Has anyone every created a list of priority safety bolts?
Appreciate your help.

jim lockwood

I hear ya regarding the cost of ARP hardware. I don't care about the cost when it comes to steering and brakes, but I am probably in the minority.

You might look into aircraft AN hardware. It has consistent quality. The bolts are a little less strong than real Grade 8 bolts. You do need to accurately measure the grip length you need. They might be less expensive than ARP, but I don't know this for sure.

One last point I can offer is that the cheap hardware store bolts sold as Grade 8 originate off shore and have miserable quality consistency. There is no way on God's green earth that I would use them in such mission critical applications as steering or brakes.

Con

Understood. Thanks.

Steve439

[QUOTE=Con;1606081494]
The fact that GM was willing to spend the money on changing the '69 and up bolts to 1/2" is pretty solid proof the originals were undersized.

Now lets talk about 7/16" wheel studs...