Deciphering Dayco belt date codes

[Scott O.]

I'm trying to decipher the original Dayco belt date codes from my 78 L-82.
The GM part numbers on my original belts match the numbers on the reproduction Quanta belts, however the rest of the numbers don't.
The Quanta belts say Gates on them.

Questions:

• Are the Dayco belts being reproduced?

• What quarter would be appropiate for a car built on 2/14/78 ?

• 4th quarter 77? or 1st quarter 78?

Belt numbers (size is highlighted in Red):
Air Pump Belt-GM9433616 AS .380 x 33.0 Dayco 5-7271 4:N:2 13
Pwr Steer Belt GM 9433622 AY .380 x 36.0 Dayco 5.5864
AC Belt GM 9433918 PG .500 x 56.5 Dayco 5-877 4N3

Thanks, Scott

[Tom R.]

Re: Deciphering Dayco belt date codes

Scott

I think you'll find Quanta "the" source for reproduction correctly coded fan belts. Gates, Dayco & Good Year were all sources of belts during that period so from a judging perspective you'll be ok. I've replaced belts on my 78s with the Quanta belts.

Re your date code question, you should be safe with 4th quarter 77. That would be a reasonable date for your February 78 car. I would interpret your codes "4" as the 4th quarter. But than, it may be that the different suppliers used a different code format. I have Gates belts on the date code is P1 (1st quarter).

[Scott O.]

Re: Deciphering Dayco belt date codes

Tom,
OK, I'll order the 4th 77 Belts
How are the Quanta belts, any problema on your car?
Seems like they get mixed reviews
Thanks for the info
Happy holidays, Scott

[Tom R.]

Re: Deciphering Dayco belt date codes

I believe the set that's on the SA car I put on some time in 1998 and have probably driven 14k miles on them. Still can see name and part numbers tho they have faded. They've held up well.