Rockauto.com 5% Discount Code
They update them periodically on this GTO forum (check expiration date):
5% Discount Code: 8833E326FE2F69 Expires: July 6, 2022 Please enter this code in the ‘How Did You Hear About Us’ box to receive the discount. Please enter ONLY the discount code, no other words or numbers. All orders are placed online and the discount code must be entered before an order is...
www.gtoforum.com
It is the usual 5% code that Rockauto.com puts out regularly on various car forums.
For those not familiar, you strangely enter it into the space marked "How did you hear about us?" on the bottom of the Rockauto order page. I believe they may still send these out to previous customers if you subscribe on the order page to their e-mails.
I haven't seen any other valid promo codes for Rockauto over the years for things like free shipping. Various coupon sites list them, however, they never seem to work. If you just search on "promo code" + rockauto/rockauto.com, the 5% codes are usually listed. However, there are so many crappy coupon sites now, many of them are clogged up with old invalid codes for web stores, or invalid free shipping ones that are just click-bait for Google searches, but don't actually work.
Rockauto still has the odd system of shipping from multiple warehouses, so you often wind up paying several separate shipping charges. They do show you icons of the different shipping locations in the product listings, so you can try to find parts shipping from one location if there is more than one choice for the brand parts you want (somewhat tedious).
By the way, I just placed a Rockauto order (hadn't done one in quite a while) and noticed on the help page that they no longer have customer service by phone. You can only communicate with them by e-mail. Welcome to the future.