C3 Bumper Bolts

[Seth G.]

Can anyone tell me what the correct head markings are for the 4 rear (large) bumper bolts to a 71? Are all 4 bolts marked the same? Thanks

[Terry M.]

Re: C3 Bumper Bolts

No one will be able to tell you with certainty the head marks of the bolts (any of them) on your car unless you have the original fasteners in hand.

Fasteners were supplied to the assembly line from stocks maintained in the plant by Chevrolet part number. Those boxes of fasteners may, even likely, came from different suppliers. Those different suppliers placed their own head marks on the fasteners. It is possible, even probable, that one side of the assembly line received bolts from one manufacturer and the other side received them from another manufacturer. It is also possible, even probable, that different suppliers fasteners were mixed on either side of the assembly line. The folks working on the assembly line paid no attention to the head marks they used. Thus at best someone might be able to tell you that three or four different manufacturers head marks were typical during a given time period, but no one can tell you what head marks actually appeared on your car except perhaps, given the right circumstances, you.

[Seth G.]

Re: C3 Bumper Bolts

Thanks. The two inboard bolts are marked "m" while the two outboard bolts are marked B-W-R

[Terry M.]

Re: C3 Bumper Bolts

Thanks. The two inboard bolts are marked "m" while the two outboard bolts are marked B-W-R

I haven't done chassis in a long time (thankfully) so some others might want to add to this, but RBW is a common mark for early C3s. I would also expect TR. There are likely others as well.

[Alan S.]

Re: C3 Bumper Bolts

Hi Seth,
My 71 has the original bumper and bracket mounting bolts it left St. Louis with.
The outer bumper to bracket bolts are marked RBW with a dot under the R.
The inner bumper to bracket bolts are marked M.
To illustrate Terry's point of head markings varying... the bumper to frame bolts (2 each side) are F in a circle on the left side, and A on the right side. So there can be variation from car to car, and even on the same car.
Regards,
Alan