Been a big fan for years. My 2018 Mazda3 just went over 60,000 miles and I live in south Florida. I'm not really mechanically inclined but I can follow directions well. I want to prolong the life of this car as long as possible. I've read conflicting things so I need some help. I found my radiator drain plug. Is it true that I cannot just open the drain plug when the car is cold and refill the tub to the full line? I've read diluting older coolant with fresh coolant can hurt the engine? I don't want to attempt a flush. Also brake fluid, it's getting a little darker and I saw a video about pumping out old fluid from under the hood and refilling with fresh stuff, but everyone says that you need to bleed the system after. I don't want to mess with trying to bleed the system, but like the idea of putting some fresh fluid in. Lastly how hard is it to change the transmission fluid in this car? It's a 2018 Mazda3 2.0L with an automatic transmission. Thanks for the advice in advance. God Bless you and your family.
I found my radiator drain plug. Is it true that I cannot just open the drain plug when the car is cold and refill the tub to the full line?
You could but that will leave lots of dirty coolant in the engine.
I've read diluting older coolant with fresh coolant can hurt the engine?
I've never heard that. As long as the same chemistry coolant is used it won't hurt anything. You just won't get the benefit of having completely fresh coolant.
I don't want to attempt a flush.
There's not much in the way of risk when it comes to flushing a cooling system. However the best way to do it varies depending on the vehicle.
It's not quite as easy as simply turning a valve and watching the coolant drain until it stops. You want to thoroughly clean the radiator by itself, then the heater core by itself, and the actual engine needs cleaned out. Then you need to hook up the radiator, heater core and engine back up to each other. Fill up the radiator as much as you can, then put the car on an incline, so the heater core is below the radiator. When the car is level, that's the highest part. Start the car and gradually add coolant until it's topped off. Use a 50-50 mix of whatever coolant is in your owner's manual.
If you don't have a transmission dipstick, then you will need to do it manually, and with some precision. Take the pan off, being careful to not spill any, measure how much was in the pan and put that same amount of new fluid back in the transmission.
I found my radiator drain plug.
Usually they're seized on there pretty well and the plugs are usually plastic and in very awkward places, so you may break it trying to open it. I find it much easier to just remove the bottom hose
Is it true that I cannot just open the drain plug when the car is cold and refill the tub to the full line?
that's only half the coolant. There's still a lot in your heater core, engine, pump, reservoir and hoses. Best practice is to get it all out.
I've read diluting older coolant with fresh coolant can hurt the engine?
only if they're non-compatible coolants. But anyway, the point of changing the fluid is to get all the old oxidized sludgy stuff OUT. You said you want your car to last as long as possible, so don't half-ass it.
I don't want to attempt a flush.
why? it's easy with a garden hose and no danger.
Also brake fluid, ... I don't want to mess with trying to bleed the system
one question per post please.
You must bleed it. Again, why do the job half way?
You're too early for that anyway.
