On a 1998 Ford E-150 :
The thread on cap on your engine coolant reservoir is the pressure cap /
radiator cap
The thread on cap on the engine coolant reservoir is the radiator cap
On a 2001 Ford E-150 : The thread on cap on the engine coolant reservoir is your pressure cap / radiator cap
On a 1998 Ford Expedition : The thread on cap on your engine coolant reservoir is the pressure cap / radiator cap
On a 1998 Ford Taurus : The thread on cap on the engine coolant reservoir is the pressure cap / radiator cap
On a 1998 Ford Expedition : The thread on cap on your engine coolant reservoir is the 16 PSI pressure cap / radiator cap
On a 1998 Ford Taurus : ( the thread on cap on your engine coolant reservoir is the 16 PSI pressure cap/ radiator cap )
On a 1998 Ford Expedition : The thread on cap on your engine coolant reservoir is the 16 PSI pressure cap / radiator cap
On a 1998 Ford Taurus : The thread on cap on the engine coolant reservoir is the pressure cap / radiator cap
The thread on cap on the engine coolant reservoir is the pressure cap / radiator cap on your 1998 Ford E - series
On a 1998 Ford Taurus : The thread on cap on the engine coolant reservoir is the pressure cap / radiator cap
The cap isn't mounted on the radiator. It is mounted on the overflow tank on the driver side of the engine.
The radiator cap is on top of the radiator.