109K Coolant Change

Truck has a little over 109 kmiles. I know it is overdue for a coolant change along with other 100K service.

I'd like to do a 100% drain and fill, but my limited garage won't allow a one time shot. So, I'm thinking about an alternate to potentially achieve the same end result.

Drain radiator, fill with new coolant. This will leave about 60% old coolant. Drive for about a week.
Drain radiator 2nd time, fill with new coolant. This will leave about 21% old coolant. Drive for about a week.
Drain radiator 3rd time, fill with new coolant. This would reduce the %age of old coolant to nearly zero.

I know its a lot more FN around, but sometimes a job needs to be done within the limits at hand.

Whatcha think? Am I off my rocker with these thoughts?

 

A serial dilution wont give you the numbers you are looking at, as the old and new will obviously mix and then youll be draining both out in subsequent rounds.

But you are right, sometimes you gotta work with what you got. And it would certainly be better than nothing. Im about 85k on the clock now, so its something Im going have to start thinking about next summer

 

How hard is it to pop the passenger side block drain? I needed like two extensions and a 10mm (or something).

The whole thing took 20 minutes.

 

@SR-71A: Yes, I know my math is a bit off.

This is how I'm figuring.....based on quantity of old coolant.
1st: (10.1-4)/10.1 = 60%
2nd: (0.60*10.1-4)/10.1 = 21%
3rd: (0.21*10.1-4)/10.1 = -##%

Based on last result in the series being a negative value......I know the math is a not correct. But, I suspect its close enough for hand grenades, shotguns and nuclear blasts.

 

The block drains are easy to access once you remove the splash guards in the wheelwells. Just buy a 3/8" drive extension (2-3 ft long). It reached the petcocks quite easily when I did mine 5 years ago. Do it outdoors if your garage is too narrow. You'll need to run the engine to bleed the system anyway, so exhaust ventilation is important.

 

Guys, Yes, I agree. Accessing the block drains is easy, assuming I have the proper equipment.

I need to replace my floor jack with a unit with more lift and capacity. Then I can place the truck on jack stands, remove the front wheels, remove the splash guards. Then I need a longer extension for my 3/8" ratchet to reach the drains. Total spend for the equipment will be near $200 before I get to the coolant at $60+. So, on limited income is easier to find $60 than it is to find $260.

Like I said, I need to work within my limits of both cash and equipment.

So, back to my original potential method. Will 3 radiator coolant changes essentially purge 100% of the old coolant?

 

drain the rad, and drain from the passenger side block drain and call it good.

After doing both of those you MIGHT get a 1/4 quart out of the bitch to get to driver side block drain so dont even bother with the driver side. Passenger side is CAKE to get to, dont even need to jack the truck up.

 

No you won't get 100% of the old coolant out. Just need to increase your change intervals. Unfortunately when you do 2nd, 3rd ...... drain and fills you also are getting rid of new coolant . Its not the most cost effective way. Some members have the same philosophy about the transmission fluid , drain and fill 3 times....

 

100% of the old coolant? No.
Enough of the old coolant for these non-precise engines? Yes, most likely.

I've been in situations most of the time I've owned my 1st gen where I don't have a place to work other than a sloped city street (both with the road crown AND vertical slope) and made it work.

I recommend doing what you can and then reduce the interval for next time when you have the resources to do a full flush. No need to overthink this with coolant. Just make sure you get the right dilution so the block doesn't freeze and crack.

 

My truck is an Automatic is holds just over 10 qts. of coolant.
When I did a radiator drain only, I got right at 1 gallon of coolant.
Maybe a little less, there are 4 qts. In a Gallon.
So you won’t get 60% out on the first drain.
At least I didn’t.

You can do what you have planned.
It should work fine, you’ll just be doing more work and spending a little more than a complete drain and fill.

I don’t recommend mixing the coolant, so doing it your way will be more expensive.
Toyota SLLC is usually more expensive compared to aftermarket options.

 

What's wrong with your garage situation that you can't do a flush? I helped my buddy do a full flush on his 4runner a couple months ago we bought like 6 or 7 gallons of distilled water and bough one of those special funnels that you screw into the top of the radiator. Reved the engine a few times to cycle the clean water through. It was cake. You just need a plastic tub or something to catch the old coolant and you can funnel it back into the empty gallon jugs to dispose of it. We got 5 or 6 good flushes in till the water was nice and clean then added toyota red 50/50 back in. Took us like 3 hours cause it takes a little bit of time to drain and we may have been slightly under the influence...lol

 

Thanks for the help guys.

I did a little research to figure out how to calculate serial dilution.

It is really pretty simple. In this case, the dilution factor (DF) is the quantity of new coolant (4 qt) divided by the total volume (10.1 qt). The DF is 0.396.

The DF will be multiplied by itself for the number of times the solution is diluted. So 3 dilutions is 0.396*0.396*0.396 to equal 0.062. This is the final DF of the original old coolant. The amount of original coolant in the final mix is 0.062*10.1 to equal 0.62 qts or 20 oz.

A 4th dilution will leave about 8 oz of old coolant.
A 5th dilution will leave about 3 oz of old coolant.

It is pretty obvious that diminishing returns begin after the 3rd dilution. Hard to justify a $20 spend to remove 12 oz of old coolant.

 

Now just hope the thermostat, radiator hoses, and/or water pump don't leak soon after 14 years and 109,000 miles

 

drain radiator,drain block,refill
unless the coolant is Green or discolored then flush system

 

@3JOH22A,
Yeah, hoses will be inspected at this time. Hopefully, no issues.
The thermostat and water pump........at this point....no problems with either, but next week may bring something different.

 

You really don't even need a long extension. My recommendation, turn your wheels all the way towards the driver's side. Undo the rearward skirt in the wheel well and take a peek at the block drain. See what you think of accessing it with just a rachet and normal extension that you probably already have. The one I used was only like 10" ish long.

Amazon is always an option too.

$37 3/8 DR. 12" EXTENSION

https://www.amazon.com/Pro-Grade-13003-8-Inch-12-Inch-Extension/dp/B000V4FAMI/ref=sr_1_9?dchild=1&keywords=3%2F8+extension&qid=1602267687&sr=8-9


It'll be more effort to drain the radiator multiple times and won't do as good of a job.

 

A 22mm 6-point socket fits nicely over the wings on radiator drain valve.
It makes getting it loose a lot easier. I used my fingers to tighten it back up, and not the socket.
A spill free funnel made it a bit easier on refill.

$34 Lisle 24680 Spill-Free Funnel, Standard Adapters, 11 x 7 x 7"es

https://www.amazon.com/Lisle-24680-Spill-Free-Funnel/dp/B00A6AS6LY

 

Seriously over thinking this.

Buy 2 jugs of this
https://www.walmart.com/ip/Valvoline-Zerex-Asian-RED-Vehicle-Antifreeze-Coolant-1-Gallon/49660461

Drain rad, drain from passenger side block. Inspect fluid and as long as it's not nasty a AF, refill with valvoline with the engine running to burp it and ca it good. 30min job, 15 of which is gonna be running and idiling to temp.

 

The driver's side drain is not particularly more difficult to access than the passenger side.

If I remember correctly, my only hiccup was the silicone hoses I got were the wrong size for the block drains, so I ended up just letting coolant pool in the skid plate. I then hosed down the engine compartment and skids with my garden hose.

 

its way more of a pain as its tucked up behind the alternator, and if you do the rad and passenger side first, you are lucky to get MAYBE 8oz of fluid out of the driver side. IMO not worth it.