O'reilly as an example, does 90 days on the replaced item: https://www.oreillyauto.com/warranty
If a product is replaced under this warranty (“Defective Product”), a replacement product will be covered for 90 days from the date of exchange, or for the remainder of the warranty period, whichever is greater. This warranty for installed vehicle parts shall terminate immediately if you sell or otherwise transfer ownership of the vehicle that had the defective product installed, or if you install or use the replacement product on another vehicle.
Autozone same: https://www.autozone.com/lp/termsAndConditions#autoZone'sLimitedWarranty
AutoZone's Limited Warranty
If a part fails during the warranty period shown on your receipt, bring the part to an AutoZone store and you will receive a replacement or refund. Warranty excludes damage caused by misuse, abuse, other faulty parts, improper installation or off-road, commercial or marine use. Warranties on replacement parts cover the unused portion of the original warranty or 90 days, whichever is longer. Warranties expire when you sell your vehicle.