C1 - GM bolt #100027

[Al C.]

Can someone tell me the proper length and strength of the GM # 100027 bolt? This is used holding the front stabilizer bar.
Paragon provides "TR" headmark, no hardness mark, bolts for this application. They were the same size as my old no-headmark bolts, but It seems that only about 1/8 inch (or less) engaged threads in the frame, and the end stripped on one of the new ones. Doesn't seem like steering-grade bolts should do this.
... Al '58 #378 245hp

[Dave Suesz]

For what it's worth...

These bolts have never been disturbed on my '55, and there is about 3/8" of bolt protruding out of the nut inside the frame. Incidentally, the heads on mine are completely plain, with one exception: the rearward one on the left side is marked "WB1C".

[Larry P.]

Re: C1 - GM bolt #100027

Al,
If you are referring to the front stabilizer bar that goes into rubber
grommets on top of the frame, I used clamps to get a good start on the threads
and then pulled them down.
Larry

[John M.]

Re: C1 - GM bolt #100027

Al,
I used longer bolts to pull it down and then replaced the bolts one at a time with the correct ones since I did not have a clamp handy!

Regards, John McGraw

[Al C.]

Re: C1 - GM bolt #100027

Thanks guys, but - the bolts did enter the threads, and the curved upper bracket is flush down to the lower which lies against the frame. It appears that the length is just a bit too short. So, I need to know what the bolt specs are supposed to be.
I am suprised that the bolt ends stripped - these are the same bolts Paragon sells for holding the third arm bracket. They have no hardness mark, and when queried Paragon told me they are really grade 5. I don't think a grade 5 would strip like this.
... Al '58 #378 245hp

[Alan Bishop #34929]

Re: C1 - GM bolt #100027

Al, On both of my 61's the bolts were 3/8 fine threaded bolts 1 1/2 inch long. (the bolts were identical on both cars when I took them apart for restore) On both cars the heads had a small ( R ) in the middle of a otherwise very smooth surface.

I also had to use 2" long 3/8 fine threaded bolts to tighten down the rubber bushings, then I switched them out. I am sure the factory used a press on this operation.

Alan

[Al C.]

Re: C1 - GM bolt #100027

Alan,
very interesting - these bolts are only 1-1/4!!! No wonder the ends are stripping, considering the probable incorrect hardness. Repro buyers beware....
... Al '58 #378 245hp