Radiator flush DIY

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The Assassin

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This DIY found via the internet:

Things You'll Need:
Five gallons of coolant
Crescent wrench
Distilled water
Bucket

1
Move the truck to a level surface to make flushing the radiator easier. Be sure to set the parking brake before beginning any work on the truck.

2
Open the hood of the truck and feel the outer temperature of the radiator. Wait until the radiator is cool to the touch before you remove the cap.

3
Remove the radiator cap once it's cool to the touch. Twist the cap one full turn to relieve any leftover pressure, wait a few seconds and then fully remove the radiator cap.

4
Position a bucket or tray directly underneath the radiator drain on the underside of the radiator. The drain plug should be on the driver's side on a Ram. Once in position, use a crescent wrench to remove the drain plug. Allow all of the existing coolant to drain from the radiator.

5
Take the drained coolant and pour it into a sealable container for proper disposal. Coolant is extremely toxic to people and pets. Take the old coolant to a toxic disposal company or your local auto store.

6
Close the drain plug and pour distilled water into the radiator. Then, open the drain plug and let the water drain back out. Repeat this procedure of filling and draining the radiator until it runs debris-free out the drain plug. It will take approximately 3 gallons of distilled water to complete the flush.

7
Replace the drain plug on the underneath of the radiator. Then fill the radiator with coolant to within 1 inch of the top lip of the radiator.

8
Leave the radiator cap off and start the truck. Allow the truck to run until the cooling fan turns on two separate times.

9
Turn off the engine and recheck the radiator level. If fluid level went down, add more coolant to the radiator. In all, you will need approximately 5 gallons of coolant for the Dodge Ram radiator.

10
Put the cap back on the radiator, clean up debris and close the hood of the truck.
 
Last edited:

05singlecabHEMI

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When should I think about doing thing how many miles

not sure on the miles, but i recently rolled over 64k and im starting to flush everything, grease everything, and replacing things. cant mod if your truck is broke!
 

debbieok

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reservoir question

When doing the flush, coolant remained in the reservoir/overflow tank. How do you drain it?
 

DieselDave24v

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Just a word of caution... I am sure the OP knows this but just left it out.....The cooling system should be refilled with a 50/50 mixture of coolant and water....not straight coolant.
Believe it or not ethylene Glycol (Anti Freeze) Does not displace heat nearly as well as water. A truck with 100% coolant runs a very high chance of overheating. The antifreezes only job in life is to stop corrosion / lubricate the waterpump/ and keep the water from freezing. The water does the cooling.
 

christoff

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Great write-up, I am planning on doing this next weekend.

Just one question (and hopefully not a stupid one)... what about the reservoir, will it drain out with the radiator fluid, and do you just fill it back up or what?

Thanks.
 

OverKill

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Just did mine last weekend. Replaced it with Zerex G-05.
Just bought the truck couple months ago,and for piece of mind,I went and flushed the radiator ,replaced the thermostat,and flushed/reverse flushed the heater core. Now heater,works better. Come to find out,last owner had a 180 therm. in it and I replaced it with oem 203 therm. Some scale and junk came out of the heater core. This combo. gave me better heat from the vents . Some asked about the expansion tank,just unbolt it,lift it out ,and remove the old coolant,and rinse. after refilling Rad. ,fill the tank to the cold mark. AND,Don't forget to burp the system.....:)
 

CRUZ9

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Doing it this weekend!:favorites13:
 

JPT

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Great write-up for an at home DIY.

This is nice to do in-between, but is not a coolant system flush. This does not address the heater core, and all the fluid in the engine block. The advantage of paying for a true coolant system flush at a shop is, they run fluid through the entire system.

I can tell my previous owner only did this, my heater core was clogged, but the radiator fluid was in good shape. I had to replace my heater core.
 

JPT

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If you have a sealed system, you want to raise the front end of the truck (as high as possible), then crack the bleeder valve. You may have to do this several times.

If you have an open system, open the radiator cap open and run the truck until the engine warms up. It will burp out the air once the thermostat opens up. Also run the heater on high.
 

squidler4

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After you drain the coolant and put distilled water in should you run the engine until the fans turn on to cycle the water through the engine block? Then drain the radiator again once it is cooled? I saw this somewhere else on the Internet when looking into flushing my radiator. This will be the first time I have done a radiator flush so any help is appreciated. Thx.


Sent from my iPad using Tapatalk
 

rdlangston13

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Does anyone have any pictures of this drain plug on the radiator? I will be doing a coolant flush as well as replacing all my coolant hoses in the next two weeks.
 

Ares_288

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I'll be doing this tomorrow. I'll be sure to post pics.
 

Sportznut

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XB...thanks for great pics...but I can't read the yellow typing.
 
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