The Correct Way To Drain/Fill the 4.0 Antifreeze

I just did this & found the third drain on the driver side after I filled back up but I did manage to drain 2 gallons with just the other drain & radiator. Mine was original in the 05 with 120k on the truck.. Now to try the transmission drain & fill.

 

Totoya? Ah, so. Are we speaking Japanese now?

 

I know that was really funny to you, but you do realize those posts are from 2 years ago right.....don't expect a reply

 

It was a joke (humor, jest, witticism, etc) for anyone, such as yourself today, to read. Didn't and don't expect a reply.

 

I am at 93K and thinking of doing a coolant change. Seems pretty straight forward, though the drivers side engine drain might be a PITA to access. If I just drained the rad and the pass. side engine petcock, how much fluid should I buy from Toyota? I live a ways from the dealer and would hate to not get enough, at this point I'm thinking 2 gallons.

Also, any need to flush the rad with water before refilling it or just drain/fill/enjoy?

 

I love having my vacuum filler for doing coolant exchanges. Makes refilling SO much easier and faster.

 

Best way I know of to drain and fill is to first be sure to not contaminate it with crap antifreeze mix and then DO NOT EVER drain it. If you keep the system properly maintained and don't contaminate it with crap antifreeze it truly will last the life of your vehicle.

 

At 88,000 miles, I changed the coolant in my 05 Tacoma PreRunner, 4.0 engine in the follow manner:
Step1 - drained the radiator by opening the drain plug on the driver's side of the radiator.
Warning: removing the skid plate is an absolute must in order to accomplish this.
Step 2 - on the passenger side of the engine, just above the engine mount is a drain point for the engine block, simply slide a 3/8" inch (brake hose is great) over the drain point and open it by a 10MM socket.
Step 3 - now close both drain points (the radiator and engine block).
Step 4 - I actually removed the thermostat housing and removed the thermostat that is spring loaded inside of it. Reattached the housing without the thermostat .
Step 5. Disconnect the top radiator hose which is on the passenger side. Take a garden house and push it into the radiator neck. Start the engine and let it idle. Turn water on to garden house. At the point you are doing a flush of the cooling system. You have water running through the radiator and throughout the entire cooling system and it exits by way of the disconnected top hose. Warning! It is a great ideal to ram a 1" house into the top radiator hose and have sufficient length to run to a drainage pan.
6. Step 6 - water goes clear and come out clear.
7. Shut the engine off - open the radiator drain and drain the radiator and close the drain. Open the engine block drain, drain it and close the drain point. Regardless of what you have been told, there is no drain point on the driver's side of the engine on a V6 4.0 engine.
8. Now remove the thermostat housing and reload the thermostat, or purchase a new one for about $40 or so which is what I did. And yes, I held on to my old housing for future flushing.
9. Slowly add 10.3 quarts of Toyota Long Life Antifreeze. The means that you must purchase 3 gallons and yes, it's pricey also but trust me, it is a smart buy in so many ways.

Hope this clears the fog for you. I still saved well over $100 by doing it myself and I know that it was done correctly with no "short cuts" which is always a fear of mine when I am forced to take my Tacoma to a shop for a job which is over my level of expertise which is a rare event indeed.

 

Well there is a third drain cock..hard to see and hard to get to , but its there!

 

So you used tap water to flush? Isn't that a big no no?

 

If you plan on using long life antifreeze then you do not want to use tap water for anything.

 

40 or 60 dollars for a thermostat? are you guys high???lol you can get one from rock auto for 10 bucks

 

Just did this today. I could not for the life of me get a wrench, socket, anything into the drivers side plug without taking the wheel off or other parts so I said screw it. I got 8 quarts out of it and figured that was good enough. It may be the Doug Thorley long tubes but it was a pain. Passenger side was very easy to get to. I went ahead and replaced both upper and lower radiator hoses, thermostat and housing (from Toyota it was $60 but I figure $60 every 100,000 miles isn't bad) and I replaced both the oil cooler hoses as well. I think total I spent around $150 for parts and coolant and total time was about an hour and a half just because those spring clamps are a pain. Even with a proper spring clamp tool getting them over the lip of the hose mounts sucks.

 

here is the thermostat and housing located...you have to take anything off to get to it?

 

From 2006 service manual.

1GR-FE COOLING – COOLANT CO–3

COOLANT REPLACEMENT

1. DRAIN ENGINE COOLANT
CAUTION:
To avoid the danger of being burned, do not remove the radiator cap while the engine and radiator are still hot. Thermal expansion will cause hot engine coolant and steam to blow out from the radiator.
(a) Remove the service hole cover from the engine under cover.
(b) Install a vinyl hose onto the drain on the radiator side.
(c) Fix the vinyl hose with tape.
(d) Loosen the 3 drain plugs on the engine and radiator, and drain the coolant.
(e) Remove the radiator cap.
(f) Drain the coolant from the reservoir tank.
(g) Tighten the 3 drain plugs.
Torque: 13 N*m (130 kgf*cm, 9 ft.*lbf) for the engine
(h) Remove the vinyl hose from the radiator.

Capacity
Manual Transmission 9.7 liters (10.3 Us qts, 8.5 Imp. qts)
Automatic Transmission 9.8 liters (10.4 Us qts, 8.6 Imp. qts)

HINT:
• Use of improper coolants may damage the engine cooling system.
• Use only Toyota Super Long Life Coolant or similar high quality ethylene glycol based nonsilicate, non-amine, non-nitrite, and non-borate coolant with long-life hybrid organic acid technology (coolant with long-life hybrid organic acid technology consists of a combination of low phosphates and organic acids).
• New Toyota vehicles are filled with Toyota Super Long Life Coolant (color is pink, premixed ethylene glycol concentration is approximately 50 % and freezing temperature is -35°C (-31°F)).
When replacing the coolant, Toyota Super Long Life Coolant is recommended.

NOTICE:
Do not substitute plain water for engine coolant.
(b) Check the coolant level inside the radiator by squeezing the inlet and outlet radiator hoses several times by hand. If the coolant level goes down, add coolant.
(c) Install the radiator cap securely.
(d) Slowly pour coolant into the radiator reservoir until it reaches the FULL line.
(e) Warm up the engine until the cooling fan operates.
(1) Set the air conditioning as follows while warming up the engine.
Item-------------Condition
Fan Speed-------Any setting except OFF
Temperature-----Toward WARM
Air Conditioning---Switch OFF
(2) Maintain the engine speed at 2,000 to 2,500 rpm and warm up the engine until the cooling fan operates.
(f) Squeeze the inlet and outlet radiator hoses several times by hand while warming up the engine.
(g) Stop the engine and wait until the coolant cools down.
(h) Remove the radiator cap and check the coolant level inside the radiator.
(i) If the coolant level is below the full level, perform the steps from (a) through (h) and repeat the operation until the coolant level remains at the full level.
(j) Check the coolant level inside the radiator reservoir tank again. If it is below the full level, add coolant.
3. CHECK FOR ENGINE COOLANT LEAKAGE
(a) Fill the radiator with coolant and attach a radiator cap tester.
(b) Pump it to 118 kPa (1.2 kgf/cm2 17.1 psi), then check for leakage.

 

I can also confirm the 4.0 has a drain on both sides of the block, it did on my 2006 and does on my 2012.

 

I changed my coolant in november, and yes, there were two (2) block drains, exactly where pictured in the diagram. I drained the rad and pass side block drain first, then drained roughly one more litre (quart, whatever) from the drivers side block drain. I can see why guys have missed it, its well hidden, but they're both there.

 

It's in the center of the front of the engine, to the left of the oil filter if you're looking at the engine from the front of the truck. It's black and angles down with a radiator hose attached that goes to the lower part of the radiator where the radiator drain cock is. You can get to it without disconnecting anything else but the hoses are cheap and good insurance. I normally replace hoses and thermostats around 100k just so I don't have to do it on the side of the road one day. Since I was doing the coolant anyways, figured why not.

Yeah, both drain cocks on the block are there, just the one on the drivers side is a pain to reach.

 

Seems like a pretty good coolant flush post. I just have one question though; how are you guys getting coolant back into the engine motor block? The thermostat is closed when u first turn on the engine and when u fill the radiator I don't think it fills up the engine block all the way I believe. hope somebody with more experience can shime in on my question. The thermostat does not open on vapor heat alone it opens on liquid thermal and when u first start the engine one side of the thermostat is cold coolant from the radiator hose and the other could be nothing or very little coolant. Hope u folks are not causing slight damage to your engine block by running it without coolant for a few minutes before the thermostat opens up. Maybe once you drain the old coolant from the engine block you can re-fill with new coolant into the block, I would just to be on the safe side. Get a small hand pump with a vinyle tubing and pump new coolant back into the engine block before even starting to fill up the radiator.

 

The pump circulates coolant even before the thermostat is open.

They have come a long way since the olden times when this wasn't the case. Follow the procedure above and you will have no problems.