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**pjmoreland** · 01-17-2022, 02:22 AM

11/22/2022 - All sets sold

These are 3/8-16 flanged bolts with a hex tip. I used a set of these to mount a Boyd tank under the bed of my '68 truck, and they worked quite well. The hex tip is used to prevent the bolts from rotating while tightening or loosening. The studs are just long enough to be used with 3/32" rubber pad between the tank and frame, along with a washer and deformed locknut. These bolts are found on 96-99 Chevy trucks with a 350 Vortec engine. The GM part number is 12557811, and they sell for about $6 each online, plus shipping. The power steering pump uses two of these bolts. It took me a decent amount of time at the wrecking yard to remove these from 6 trucks, thus the price.

$20 shipped for a set of 6

See the following thread for more information on how these bolts were used.

https://67-72chevytrucks.com/vboard/...d.php?t=828999

Here's the rubber pad I used:
https://www.mcmaster.com/8610K83/

01-17-2022, 02:22 AM	#1
pjmoreland Senior Member Join Date: Jan 2005 Location: CA Posts: 5,349	Mounting Bolts for Under Bed Tank 11/22/2022 - All sets sold These are 3/8-16 flanged bolts with a hex tip. I used a set of these to mount a Boyd tank under the bed of my '68 truck, and they worked quite well. The hex tip is used to prevent the bolts from rotating while tightening or loosening. The studs are just long enough to be used with 3/32" rubber pad between the tank and frame, along with a washer and deformed locknut. These bolts are found on 96-99 Chevy trucks with a 350 Vortec engine. The GM part number is 12557811, and they sell for about $6 each online, plus shipping. The power steering pump uses two of these bolts. It took me a decent amount of time at the wrecking yard to remove these from 6 trucks, thus the price. $20 shipped for a set of 6 See the following thread for more information on how these bolts were used. https://67-72chevytrucks.com/vboard/...d.php?t=828999 Here's the rubber pad I used: https://www.mcmaster.com/8610K83/ Attached Images Last edited by pjmoreland; 11-23-2022 at 04:18 AM.