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60wag
09-12-2010, 11:44 AM
I did a coolant (Toyota red) drain and fill on the 80 yesterday since its been three years since the last one. I know we tend to overdue the preventive maintenance on our trucks due to our intense interest in them, but how long should coolant last?


My wife's '04 SAAB is due for an oil change and I thought I might as well do the coolant since its likely original juice. I went to look up the type of coolant and capacity so I would know what to buy. It's like 7.8 quarts of Dexcool. It also says the coolant is good for the life of the car. Now either they don't expect the car to last very long or Dexcool has some fancy buffers in it the can keep the acidity down for a long time.

What do you think, Change it or leave it?

rover67
09-12-2010, 12:35 PM
I don't know, but it's funny that you bring it up.. I was changing the oil yesterday in the 2000 Jeep Cherokee we've somehow adopted and figured I might as well do the coolant...

it only has like 50k miles on it but the coolant looked kinda like it could use to be changed just because it was kinda mirky.

I say do it.. why not? it's cheap and relatively easy.

I also threw a new radiator cap on there for good measure. Not like it was overheating or anything, but it was like 4 bucks at NAPA. If it was anything other than the jeep i'da gotten an OEM one, but NAPA's cheap mexican parts are basically OEM for the Jeep anyways.

I don't know... interested to hear what others say.

nuclearlemon
09-12-2010, 01:59 PM
an auto parts store will have test strips you can buy that will tell you how good the coolant is and what the mixture is rated for.

60wag
09-12-2010, 03:51 PM
I went ahead and put new juice in. I was at the parts store getting some oil and picked up a jug of orange dexcool. It's quite easy to change the fluid on a SAAB 9-5. The rad drain is a quarter turn deal that opens up a drain hole that is pointed straight done. And, get this, its made to easily shove a hose on so that the coolant doesn't splatter all over the place - unlike the more familiar Land Cruiser. On both my 80 and my old 60, draining the rad meant several catch buckets and several old towels to mop up the mess on the garage floor. Toyota engineering is good but there are some features that I wish showed up on Cruisers. Additionally, the SAABs use a pressurized overflow bottle so there is no cap on the radiator. Its on the plastic bottle instead. This makes draining and filling the system simple - just poor until the liquid level is up to the full mark. Any bubbles in the system are easily expelled to the bottle.

I have a coolant tester that showed the old mix was ok for freeze and boil over protection but I was wondering how acidic the stuff becomes after being in the car for 6 years.

Speaking of acidic liquids - did anyone else here catch the Radiolab show on national public radio today? The episode is titled "Oops" and has some amazing stories of oops, one involving a lake of acidic mine water that is just too wierd to be true.

nuclearlemon
09-12-2010, 03:56 PM
I have a coolant tester that showed the old mix was ok for freeze and boil over protection but I was wondering how acidic the stuff becomes after being in the car for 6 years.



that's all the coolant testers will test. you need to get the test strips that test the ph, etc.

74fj40
09-12-2010, 08:05 PM
All BMW's and Mini coopers are 4 year life span. would say that is pretty normal life span for coolant...

Rzeppa
09-13-2010, 10:58 AM
I did considerable research on this topic when I was offered some unused, but old ethylene glycol. It turns out that the "corrosion inhibitors" that they add to automotive coolant are simply buffers to react with any acid found inside the cooling system. Eventually they are used up and the coolant becomes acidic and will start to corrode the surfaces inside your cooling system. The "test strips" are simply litmus paper.

subzali
09-13-2010, 12:20 PM
so are you aiming for a neutral pH (~7) when you do the tests?

nuclearlemon
09-13-2010, 05:14 PM
I did considerable research on this topic when I was offered some unused, but old ethylene glycol. It turns out that the "corrosion inhibitors" that they add to automotive coolant are simply buffers to react with any acid found inside the cooling system. Eventually they are used up and the coolant becomes acidic and will start to corrode the surfaces inside your cooling system. The "test strips" are simply litmus paper.

basically, yes, there are 3 way and 4way test strips that molybdate, nitrate, freezepoint and i can't remember the fourth thing (we only carry the 3way test strips here).

Rzeppa
09-14-2010, 10:51 AM
so are you aiming for a neutral pH (~7) when you do the tests?

No, higher than that is my understanding, as in slightly alkaline (~8-9ish).

powderpig
09-14-2010, 11:28 AM
I would not let any green coolant go more than 2 years. best is every year. Even this new long life stuff should not stay in longer than 2 years(IMHO). Additives that prevent electrolsis do not last as long as these companies represent. If you want to have the coolant last longer, install a coolant filter with additive packages to protect against electrolsis and other corrision(just like a diesel).
It has been a few years since I have looked into this stuff, but gates had some great info on coolant and such. We here in the US have a open system which allows oxygen to get into the coolant system. With this indtruduction of O2 into the system the fluid degrades. Over in europe, the systems are closed and do not allow the fresh introduction of O2 into the system, so the coolant can last longer.
That was from some studies a few years back.

thisGuy
09-15-2010, 02:54 PM
damn mines been in my car for 12 years.. I would add water to it here and there but outch!

I added a gallon of dexcool (the universal green one) i think it was dexcool, to my car last year.

i guess maybe its time that i change that huh?

it would be the life of the car seeings how it would eventually kill the car.