I have to change the power cord of my dryer. the new power cord has 4 pronge. the 4 wires colors are red,white,black and green. on the dryer i have only 3 wire: red,blue,black. i want to know witch wire goes with witch colors.(ex: power cord white with blue on dryer) thanks

Unplug the dryer then remove the terminal block cover and disconnect the 3-prong cord from the dryer. Note that the cord has red , black, and white wires but sometimes the red and black wires are both replaced by same color wire, usually gray and can switch places. There's also a ground strap wire also connected to the center terminal together with the white (neutral) wire.

Get yourself a 4-prong cord and note that it has red, black, white, and green/yellow wires but sometimes, like the 3-pronged one, the red and black wires are both replaced by same color wire, usually gray and can also switch places. All you have to do now is connect the 3 wires in the same manner they are connected as 3-prong cord to the terminal block. The ground strap wire now just need to be connected to the remaining 4th wire, the green/yellow wire instead of the center terminal together with the white (neutral) wire. Reinstall the terminal block cover and it's done.

It can be observed that converting a 3-prong cord to 4-prong cord is merely splitting the neutral line and the ground thereby increasing the number of prongs from 3 to 4 whereas, on the other hand, converting a 4-prong cord to 3-prong cord is merely joining the neutral line (white) and the ground (green/yellow) thereby reducing the number of prongs from 4 to 3.. The links below might enlighten you further on this matter.

Four-prong to Three-prong Electric Dryer Conversion
Three-prong to Four-prong Electric Dryer Conversion

Hey white to white, black to black red to the multi colored pole, and the green one is the ground wire,, . I done that before,, lol,, good luck ,, thanks

It's either you convert the 3-prong outlet to 4-prong or the 4-prong cord to 3-prong. But the latter is easier and more feasible. Unplug the dryer then disconnect the 4-prong cord from the dryer. Note that it has red, black, white, and green/yellow wires but sometimes the red and black wires are both replaced by same color wire, usually gray. The red and black wires are lines L1 and L2 reversibly, meaning they can switch places, while the white and green/yellow wires are the neutral line and ground, respectively.

Get yourself a 3-prong cord and note that it has red , black, and white wires but sometimes, like the 4-pronged one, the red and black wires are both replaced by same color wire, usually gray and can also switch places. All you have to do now is connect these 3 wires in the same manner they are connected as 4-prong cord to the terminal block. The wire strapped to the dryer cabinet and connected to the green/yellow wire of the 4-prong cord wire is now left hanging. The last step is to connect this hanging strap wire to the same terminal on the terminal block (center) where the white wire (neutral) is connected and it's done.

It can be observed that converting a 4-prong cord to 3-prong cord is merely joining the neutral line (white) and the ground (green/yellow) thereby reducing the number of prongs from 4 to 3. On the other hand, converting a 3-prong cord to 4-prong cord is merely splitting the neutral line and the ground thereby increasing the number of prongs from 3 to 4. The link below might enlighten you further on this matter.

Electric Dryer Prong Conversion

The new cord has a green ground wire; two hot wires, which are black and red; and a white neutral wire. Attach the neutral to the middle connector and the two hot wires to either end of the terminal.
In order to safely ground the machine the green ground wire must be securely connected to the dryer frame. There may be a screw on the frame where you can attach the ground.

You have to replace the dryer's 3-prong cord to 4-prong. Get yourself a 4-prong cord then on the terminal block at the rear of the dryer, connect the wires of the 4-prong cord to where the same wire colors (red, black, and white) of the 3-prong cord connects to. The only modification needs to be done is on the green/yellow stripe wire that connects from the white wire terminal to the dryer's cabinet. Remove this wire (green/yellow stripe) from the white wire terminal then connect it to the same wire color (green/yellow stripe) of the 4-prong cord and you are done. The new wire configuration would then be red, black, and white on the terminal block and green/yellow stripe wire on the cabinet.

Your new cord has 4 wires. Black, red, white , green.
The dryer has 3 lugs to connect to. Connect the white and green to the center lug, connect the red to left lug and the black to the right lug. You are all set to use dryer.

Always disconnect electricity before beginning this process.

All the 4 wire cords I have seen are color-coded. The white wire goes to the middle terminal, the green wire goes to any screw you can reach that goes into the metal case of the dyer. The red and black go to the outside terminals of the block and while it doesn't matter which color goes to which terminal I usually follow the color code of the interior dryer wiring that already exists. Good Luck.

*First ; before starting unplug unit or shut off breaker.

you should be able to match up color for color on your dryer, the fourth wire, green (ground) screws to the chassis, or cabinet. if your wires aren't coded as you say, it is red, white and black, left to right. see picture I've supplied.
hope that helps

good luck

Hello wgirdler,
While it is preferred to upgrade the receptacle to a 4-prong type (which includes Neutral & Ground) Code requirements grandfather in 3-prong receptacles in older homes. So if your preference is to remove and replace the power cord on your dryer, make sure you get one that is designed for a dryer application and is 10/3 type. ( 10 Gauge wire with 3 conductors)...
Unplug the original 4 prong plug from the receptacle and pull the dryer away from the wall to gain access to the back of it.
Next, loosen the cord clamp that allows the cord to pass thru the back panel and into the druer compartment.
Open the access cover to where the end of that cord is terminated on a terminal block of the dryer.
Note which color is attached to which terminal ( red to red,black to black, white to white and green to green)...
3 Prong cables do not use a ground wire ( green) in the cord so you would wire the red to red, black to black and white to white ( The red and black are the power conductors and the white ..which is normally terminated between them.. is in the middle. You can get a seperate insulated conductor wire and route it from the ground stud of the dryer to the receptacle metal casing but do this with power disabled at the circuit breaker box...
Hope this helps.
Regards,
Rick

BLACK and RED are 110-120VAC each. WHITE is NEUTRAL - does not carry power. GREEN is GROUND. The Black, Red, and White Wires should connect to the terminal block & should correspond the colored wires already connected to the block from the machine. The Green wire should be grounded to the equipment chassis. I hope this answers your question.