Replace 10 year old coolant and spark plugs?

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karyins

New member
Guys thanks for all the informative posts! I've been reading the forum since I got a 2004 v6 SR5 not long ago. Having been in the Northeast it's kinda rusty down there but still runs like a champ! My main concern is the low MPG at 14 to 15ish. Maybe that's due to city driving mostly but still I'd like to see if I can do anything about it.

So far I had the engine oil changed. The engine air filter was replaced a year ago and it looks ok. Got new set of tires (continental lx20). Got wheel aligned.

Today I read through the maintenance guide and realized these:

1. spark plugs have never been changed (51,000 miles, 11 years) and the manual said change them every 30k so I'll get new ones for sure.

2. Engine coolant has never been changed. Manual said replace at 100k or 10 years. Do I really need to do that? The truck has no obvious heating related problems. The temperature gauge needle goes up in a few minutes drive and stays just a little below the middle of the dial.

I noticed that the pink coolant in the reservoir sits at L mark when engine is cool, and about an inch above the L mark when engine is running at operating temperature. Is this normal? Or does it mean there is air in the cooling system?

Also some posts suggested to change the thermostat while draining the radiator. Is that really necessary? I mean so far it seems working fine.

Thanks!
 
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karyins said:
Guys thanks for all the informative posts! I've been reading the forum since I got a 2004 v6 SR5 not long ago. Having been in the Northeast it's kinda rusty down there but still runs like a champ! My main concern is the low MPG at 14 to 15ish. Maybe that's due to city driving mostly but still I'd like to see if I can do anything about it.

So far I had the engine oil changed. The engine air filter was replaced a year ago and it looks ok. Got new set of tires (continental lx20). Got wheel aligned.

Today I read through the maintenance guide and realized these:

1. spark plugs have never been changed (51,000 miles, 11 years) and the manual said change them every 30k so I'll get new ones for sure.

2. Engine coolant has never been changed. Manual said replace at 100k or 10 years. Do I really need to do that? The truck has no obvious heating related problems. The temperature gauge needle goes up in a few minutes drive and stays just a little below the middle of the dial.

I noticed that the pink coolant in the reservoir sits at L mark when engine is cool, and about an inch above the L mark when engine is running at operating temperature. Is this normal? Or does it mean there is air in the cooling system?

Also some posts suggested to change the thermostat while draining the radiator. Is that really necessary? I mean so far it seems working fine.

Thanks!
Click to expand...

that fluid is going to look pretty bad once you take it out. Id suggest replacing it. if you are tight on cash, you can probably go another few months, but you prolong these things you might get other problems. be sure to get the toyota coolant, it makes a difference..

how did you get such a low milage car? Just sure hope someone didnt turn back the meter on you.
 
Yes, change that coolant. Coolant gets acidic it as it ages. I did mine at 5 years because I've always done it that way. In thirty years of driving, I've never changed a water pump on a system that I maintained.
 
yes, change it. fyi, you actually don't need to flush it, just drain as much as you can and refill. that should be good enough. at some point, your radiator will start leaking and then you'll be replacing it again. don't ask me why. :)

in my case, I end up replacing my radiator, cap, thermostat and coolant at the same time due to the radiator leak before it reached 100000 miles. my car at the same time is 10 years old. your reservoir should read at the low point when cold and at the high point when warm. that's normal. if you could do it all at once, that would be better. at least you'll know it's not going to fail on you on a long drive. :)

karyins said:
Guys thanks for all the informative posts! I've been reading the forum since I got a 2004 v6 SR5 not long ago. Having been in the Northeast it's kinda rusty down there but still runs like a champ! My main concern is the low MPG at 14 to 15ish. Maybe that's due to city driving mostly but still I'd like to see if I can do anything about it.

So far I had the engine oil changed. The engine air filter was replaced a year ago and it looks ok. Got new set of tires (continental lx20). Got wheel aligned.

Today I read through the maintenance guide and realized these:

1. spark plugs have never been changed (51,000 miles, 11 years) and the manual said change them every 30k so I'll get new ones for sure.

2. Engine coolant has never been changed. Manual said replace at 100k or 10 years. Do I really need to do that? The truck has no obvious heating related problems. The temperature gauge needle goes up in a few minutes drive and stays just a little below the middle of the dial.

I noticed that the pink coolant in the reservoir sits at L mark when engine is cool, and about an inch above the L mark when engine is running at operating temperature. Is this normal? Or does it mean there is air in the cooling system?

Also some posts suggested to change the thermostat while draining the radiator. Is that really necessary? I mean so far it seems working fine.

Thanks!
Click to expand...
 
Guys thanks for all the wonderful inputs! I know this site would never fail me!

Do I need to bleed the air out of the cooling system after draining and refilling? Saw some youtube videos doing that.

Thanks!
 
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Yes. You will probably need to burp the system unless you want to hear a gurgling sound every time you start your truck.
 
I did my spark plugs over the weekend. Turns out i had the factory plugs in for 130k! ( don't blame me I got the car at 96k)

Anyway, don't expect to find the correct plugs at your auto parts store so i would plan a few days ahead in case you need to order them or you can go to toyota but i think they charge about 5$ per plug.
 
It is normal for the coolant level in the reservoir to change with temperature/vehicle rpm. As long as it is above the Low mark I would not be too concerned (unless the reservoir suddenly overflows... lol)
 
I've never changed a water pump on a system that I maintained.
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Growing up in the days when old guys put hose water (bad West Texas hose water) in the Rad.....I changed many water pumps, a few chevy "freeze" plugs and usually pretty often.

I learned my lesson and back in the days of the GREEN stuff it was an annual maintenance item, with a couple jugs of distilled water. Now the new chemicals are so much better those intervals are 3x and 5x longer but its a ritual !
 
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