Car Guys: When to do Radiator Flush?

[Car-Guy]

I went to my Subaru dealer for oil changes which were free until the warranty ran out. The reason I did was to have proof that the oil changes were done according to manufacturer's specs in case of an engine problem. I also had them print the receipt just in case their computer "lost" the records.

Actually, I'm not really to worried about a "reputable dealer" denying valid warranty claims... They make a lot of money on warranty work.... Of course there are the "horror stories" and/or you can always run into an a**hat...

In my case, for vehicles I've had under warranty, I keep records of my DIY maintenance along with the receipts to prove I purchased the "correct oil", filters, fluids, etc.... In over 50 years of driving new cars, I've never even been asked to show them.... I've also known a couple of dealership mechanics over the years and they all told me basically the same thing... They can tell when they tear into an engine or transmission if it's been "maintained" and/or abused. I know I can pickup on poor maintenance issues pretty quick when I work on a motor or transmission....


But as they say, YM (and opinion) MV

 

[teetee]

Personally, I've always used the drain value near the bottom of radiator.... Of course you could just remove one end of the bottom radiator hose for a drain, if you really wanted or needed to. For me, the valve is usually easy to find and the complete job can be done in about 30 mins.... But that's me...

I understand some manufactures have done away with the radiator drain valve altogether but I haven't run across that yet. I just don't keep new cars long enough to worry about it.

Oh sorry for the misunderstanding. I still think all radiators have drain plug / valve but not all engines provide the (accessible) drain port. Some just assume thermostat port or the air intake valve would be sufficient but neither of those are placed at the lowest point of the engine block that is why I mentioned only the engine part.

With or without engine coolant drain port, after 3 or 4 flushes with 10min running idle each time with just water and max interior heating setting should be sufficient to flush everything out unless the heater core is clogged than reverse flush for the core with some pressure will help.

 

[Bamaman]

I have a strong family rule. Never return any vehicle to an automobile dealer's service department unless the manufacturer is picking up the bill 100% for a warranty repair or a recall of come kind.

Luxury dealers especially eat the pocketbooks of their customer.

And my family owns the Lexus dealership I avoid so well.

Modern cars have engine blocks and heads made out of aluminum, and they don't have the rust in them that the old cast iron engines had.

My Ford F250 diesel pickup is 18 1/2 years old, and I've never even added any antifreeze. The antifreeze is as clear as when it was new.

My Lexus does need a new thermostat as it heats up very slowly. I will flush it when I do that replacement.

 

[Jerry1]

I will flush it when I do that replacement.

This is another good point. When working on a auto component, replace the adjacent equipment as reasonable. For example, if I have a water pump go bad and assuming the other equipment has not been already replaced, like the belts that need to be removed to get to the pump, replace them. If I had to take a radiator out, ever hose attached to the radiator should get replaced. The cost for most of these repairs is primarily the labor, so if you’re already paying for a belt removal, replace it with a new one. Basically, do the things that make sense while the mechanic is in there.

 

[Nick12]

This is another good point. When working on a auto component, replace the adjacent equipment as reasonable. For example, if I have a water pump go bad and assuming the other equipment has not been already replaced, like the belts that need to be removed to get to the pump, replace them. If I had to take a radiator out, ever hose attached to the radiator should get replaced. The cost for most of these repairs is primarily the labor, so if you’re already paying for a belt removal, replace it with a new one. Basically, do the things that make sense while the mechanic is in there.

I did the same with my previous Honda. When it came to the timing belt getting replaced, I requested the water pump and the belts replaced too. The air filter and cabin air filter I just bought the factory part to replace. It is not rocket science. The Honda dealer charges $90 part and labor to replace the cabin air filter. It takes me about 2 min to change it out. The part costs $30.

 

[CRLLS]

I have never changed, drained, flushed antifreeze simply for the sake of the change itself. As said earlier by others, I have changed antifreeze in the course of performing other service such as replacing a radiator, removing a head for valve train repair, or changing out a timing belt. Sometimes a 10 to 50 year old car does need repairs. I change out the antifreeze then.

I have found only one place near me that will take and recycle my used antifreeze.

 

[RetireeRobert]

I have a 2018 Audi Q5, 43,000 miles. I had my car in for another routine service, and they "recommend" radiator flush. They didn't say I NEEDED one, just that with my current odometer reading it's a good preventive step.
Maybe I missed it but I can't find anything in my manual about it. My car is running fine. Is there a standard mileage/time I need to get this done? .

At 3 years old and 43,000 miles your Audit does NOT need a radiator flush. Way too early.