Coolant change question

Today I drained the coolant in my new-to-me 2014 with 149k miles. I have no info about this maintenance ever being performed before. I drained the radiator and expansion tank, but not the block. All told, it took just less than 1 gallon to refill.

My question - should I drive it for a bit and then repeat the process? I feel like if I got 2 gallons of new coolant in there it should be 'good enough'. Or is that unnecessary, and the 1 gallon is ok?

 

You should drain the block
It is easy and gets much more out

 

I'm lazy, don't like working on vehicles. And I loose interest fast when I have to deal with fluids too.
I just drained the radiator in the spring, then did it again in the fall. And called it good for 5 years.
No way I was going to touch those block drains after 13 years. My luck would have them break off, or leak.
And it was also a good excuse not to have to remove the wheels. The driver side isn't "easy" to get to.

I'm not saying you should follow my advice. But.....

 

Most people on here will tell you to drain the rad, expansion tank, and passenger side block drain. That gets something around 75% of the old coolant out and most people call that good

 

You summed me up pretty well. Even the radiator drain was a bit sketchy for me. I kept repeating "don't break, don't break..."

 

You can actually use a socket on that radiator drain and it works well. I don’t remember the size though.

 

It's nice to drain the block, but as @TnShooter suggests, there is risk involved.

My technique on many a hi mile ride is pretty much what you are suggesting. But I do it every couple of days until what I drain looks as clear coming out as it did going in. At the end of the cycles I usually include a new t stat and radiator cap, just because.

While having an empty system and refilling it with premix is nice, once you know the system capacity and how much you actually drain out, you can refill with straight antifreeze and it will create a reasonable mix.

If I lived in the icy hinderlands I'd not do it that way. But in the S as you and I are, freezing is less critical, so having the perfect mix is less critical.

Side note. I once opened up an engine that had only run 100% antifreeze since shortly after new. It probably had the cleanest water jackets of any vehicle I ever saw.

 

+1 to this.... eff the driver side block drain. Simply park the truck on a decent uphill and jack up the front driver tire to lean the truck back and passenger, doing so with just the passenger block drain gets damn near all the coolant out, I had less than a quart left of 2 gallons upon refill after doing this method of drain recently.

 

https://www.tacomaworld.com/threads/sticky-radiator-drain-valve.765117/