Brake disc to front bearing hub bolts T/C

[kram350kram]

In changing the brake disc rotors I noticed the 4 retaining bolts had two raised lines on their heads crossing at 90 degrees. Have never seen this making and can't find anywhere except standard AN aircraft bolts have a somewhat similar marking. Anyone know what these bolts are, (grade 6 maybe?). Worth changing to grade 8 while here? Thanks in advance.   

[BDA]

It sounds like AN bolts. Why don't you post a picture?

[jbcollier]

Stock disc bolts are already a higher grade.  The width and length of the shoulder is critical.  The bolts have not been a problem in use.  I have happily reused them many, many times.

[kram350kram]

T/C HUB BOLT

[BDA]

That's not an AN bolt. I think JB is right that it's a stock bolt for that purpose and you can reuse it without worry.

[Chuck Nukem]

Mine were pretty corroded so I switched to AN. If they had been better I would have reused as well.