Keep coolant moving between the engine and radiator with the Dayco Radiator Coolant Hose (MPN 70621). This is the upper radiator hose position, a flexible coolant hose that carries hot coolant along the upper circuit so the cooling system can shed engine heat. It's a direct-fit replacement for a wide list of 1968-1979 Buick, Cadillac, Oldsmobile and Pontiac applications (see the full list below).
- Upper position: serves the upper radiator hose connection on the listed vehicles.
- Coolant circuit: routes coolant between the engine and radiator to help maintain proper operating temperature.
- Direct fit: a direct-fit replacement for the original hose on the listed applications.
If a cracked, swollen, or leaking upper hose is the cause of coolant loss or overheating, this replaces it. Inspect clamps and connections during installation and refill with the correct coolant per the vehicle's service information.
Interchange: 26013X · 3683 · MC29 · C0683 · C1007 · MH393 · 20683 · CH75 · 60714 · 006 · 21007 · 5041 · KM465 · 7457 · 7736 · H314 · H316 · MR117 · MR159 · MR855 · RH10 · CH466 · MC21 · Manufacturer part number 70621.
Fitment: 1975-1977 Buick Century · 1976-1978 Buick LeSabre · 1975-1977 Buick Regal · 1975-1979 Buick Skylark · 1968-1976 Cadillac Calais · 1970-1976 Cadillac Commercial Chassis · 1968-1976 Cadillac DeVille · 1968-1976 Cadillac Eldorado · 1968-1976 Cadillac Fleetwood · 1977 Oldsmobile Cutlass · 1977 Oldsmobile Cutlass Supreme · 1977-1978 Oldsmobile Delta 88 · 1977-1979 Oldsmobile Omega · 1977-1978 Pontiac Catalina · 1977 Pontiac Grand LeMans · 1977 Pontiac LeMans · 1977-1979 Pontiac Phoenix · 1977 Pontiac Ventura. See the "Vehicles it fits" section for the full list.
Product information is for general reference and may contain errors. See our Disclaimer.
This part cross-references / interchanges with the following part numbers:
26013X, 3683, MC29, C0683, C1007, MH393, 20683, CH75, 60714, 006, 21007, 5041, KM465, 7457, 7736, H314, H316, MR117, MR159, MR855, RH10, CH466, MC21, 1249057, 1252710, 1489534, 1492694, 1494142, 1494291, 1601434, 1602026, 1605708, 1606792, 1608333, 1608503, 546763, BH1124, BH1694, 77-8407-7
Frequently Asked Questions
What is this part?
It's the Dayco Radiator Coolant Hose, MPN 70621 — the upper radiator hose that carries coolant between the engine and radiator on the listed applications.
Is this the upper or lower hose?
This is the upper radiator hose position for the listed vehicles.
What vehicles does it fit?
It's a direct-fit replacement for various 1968-1979 Buick, Cadillac, Oldsmobile and Pontiac models. Check the "Vehicles it fits" section to confirm your exact year and model.
What are signs this hose may need replacing?
Cracks, swelling, soft or brittle spots, and coolant leaks are common signs. If a failed upper hose is the cause of coolant loss or overheating, this replaces it.
What numbers does it interchange with?
It cross-references numbers including 26013X, 3683, MC29, C0683, C1007, 20683, CH75, 60714, 21007, H314, H316, MR117, MR159, MR855, RH10, CH466 and MC21.
