Your cart is empty
Browse our catalog to find the parts you need.
These images are illustrative and may not match the product exactly. Always verify by part number — or confirm instantly with the assistant using a photo or VIN.

Chelsea · Drivetrain
21P572
In stock · ships from Knoxville
The Chelsea 21P572 (also listed as 21-P-572) is a 4-bolt RB pump flange used to mount a hydraulic pump onto a Chelsea power take-off (PTO) unit on a truck transmission.
Confirm the part fits before you buy. Applications and interchange numbers are researched and audited per part.
Verified fitment for 1 applications
Add your truck to see whether it's one of them
All confirmed applications for this part number.
Other applications
Other applications
Designed for Chelsea PTOs; verify compatibility with your pump's bolt pattern and shaft size before installation.
Part data verified against 5 catalog sources
Numbers this part supersedes or interchanges with. Showing 1 of 1.
Different year, make, or config? Get a confirmation against your truck in under a minute.
It serves as the bearing cap and mounting interface for typical 4-bolt hydraulic pumps, allowing PTO-driven hydraulic systems for dump bodies, cranes, or other equipment. This flange is replaced when the original is damaged, worn, or missing, ensuring a secure seal and correct alignment.
Part Number: 21P572
FLANGE
Vendor: Weller Truck Parts
Dealer: Knox Trailers
Compatibility, alternatives, and more