The Correct Way To Drain/Fill the 4.0 Antifreeze

The passenger side block drain was stuck tight on my truck and I was afraid to torque it too much, lest I break it and be screwed. So I hit it with PB blaster every couple of days for a week or so and I finally got it broke loose. I have a 14" 1/4 in drive socket extension that is perfect for this drain (works awesome for the spark plug coils as well). Not sure I'm going to fool with the driver side drain, I've heard only about 12 oz of fluid comes out anyway. Not worth the effort in my opinion.

 

yea, if you give it a cleaning agent water flush and then a water only flush after that, then I do not see much problem not doing both, I always do both but mine are not stuck and I would be afraid of breaking them if stuck. I used like 4 extensions on mine lol

 

I’m about to change the coolant in a 2012 Tacoma I bought with 121K miles and the original Toyota Coolant.

Do you guys think it would be necessary to replace the theromstat? Reading some people who have done it in this thread, but not sure how long thermostats typically go...
The radiator hoses look fine and show no signs of cracking so I might hold off on those.

 

I did my thermostat at 130k, it looked great (see pic). Def didn’t need to be replaced. But, it was $30 for a OEM part and easy to install, so I changed it out. I also replaced the upper and lower hoses with Gates hoses. I also replaced the radiator cap since I was on a roll.

I enjoy doing maintenance, I hate doing repairs.

 

Thanks for the reply. Yeah, your thermostat looks excellent. I definitely don’t remind replacing it, but if it doesn’t necessarily need it, at this point it will just be preventative maintainance.

Have you heard of thermostats going bad after the first initial coolant change? My radiator hoses don’t show any signs of wear other than being dirty.

 

The stealership changed my coolant (or at least charged me for doing it) at 85k and my thermostat didn’t mind.

 

Excelente grupo será de mucha ayuda.

 

This line alone is huge. 1000% correct.

 

Would this work instead of messing with the 2 block drains? After draining the radiator, take an old radiator cap and adapt a fitting for a compressor and just push out the remaining fluid with a compressor and 10lbs of presure. Wouldn’t it just force it out the bottom of the radiator?

Edit: never mind, It just dawned on me why this won’t work. Duh

 

Question. I am going to just drain the radiator and reservoir, then fill it with distilled water to clean it out and drain again. When i go to fill the new coolant into the radiator, do I leave the radiator and reservoir cap off so i can squeeze the hoses to get the air out when the engine is running, or do i close it up and let the truck warm up and then squeeze with the caps closed.

Thanks in advance

 

i do not recommend opening or leaving the cap off when running

 

How about Peak Global if doing a full flush? Claims to be non-2EHA.

 

Just recently completed 3 drain and fills with with Valvoline Zerex.

Just thought I would share this in case it's not been mentioned yet. But if you're having trouble getting your fingers or pliers on the drain-cock plug....a 22mm socket will grip it

 

Thanks to everyone for contributing to this thread. Great info! I recently bought a used '06 with just under 160k. I'm not sure about the maintenance that's been done so I'm going through things little by little. I just ordered a new t-stat, gates hoses and a new cap. I also bought 2 gallons of Zerex Aisian coolant that I'll be refilling with.

After that will be PS and ATF with Maxlife ATF.

 

The system should burp with cap on. Are you going to circulate distilled water or are you just trying to rinse the radiator? It seems like either way you will get distilled water into the system and then need to buy concentrated antifreeze, track the amount of water added and amount drained to figure out how to make 50/50 mix again. Even draining the engine block drains leaves some antifreeze in the system.

I just drained radiator and engine block and added Toyota Super Long Life back in. I already had the 50/50 Toyota stuff so didn't flush.

knottyrope says: Want to flush it?
Run a garden hose through it and idle engine for a while until clear
Flush with distilled water twice or more ( buck a gallon at supermarket)
add in the pure coolant (1/2 of system capacity) and then add your distilled water to the top

 

if you can get the plug completely out you can just match it up with a metric sized bolt the same size

 

That part has a funny name

 

I know this is an old thread folks so bare with me, I posted a few years back that that I had 10yrs and 160k miles on my truck with the original factory coolant. Now it's 13 years and 213K miles with still original factory coolant and thinking about replacing my coolant for the first time. I read about electrolysis and it stated it needed to be .300 dc volts(300milli volts) for electrolysis to occur. Here is what I found in mine, .169 dc volts with no issues and truck drives flawless still. ORIGINAL FACTORY COOLANT AND 13 YR OLD TRUCK. I still say that you folks changing your coolant at 60-70k are wasting your time & $$.

 

@esse10
.3v+ requires immediate attention. .1v to .3v shows electrolysis activity.

As has been pointed out, there are other factors to consider. It only costs about $25 to get two concentrated SuperTech universal coolant bottles to replace the OEM coolant. Surely, your truck is worth it. Especially considering 05-06 models have higher rates of head gasket failure than normal.

 

where did you get those numbers from? .1-.3 I read that all trucks , even the new coolant will read .1 mine showed .165 even after 13 years.