Coolant Change
Thread Starter
Drifting
Joined: Jun 2004
Posts: 1,484
Likes: 20
From: FLORIDA
Coolant Change
Does any body have any views on when to change the Dex Cool Coolant in a C-5?
The manual says 5 years or 150,000 miles.
I have only 15,000 on my 99 and it looks good.
Just wondering if I should change it or not!
The manual says 5 years or 150,000 miles.
I have only 15,000 on my 99 and it looks good.
Just wondering if I should change it or not!
Safety Car
Joined: Nov 2001
Posts: 3,753
Likes: 191
From: Orange County California
Lots of cheap insurace floats around the forum LOL perhaps we should go work for Geico.
I'm sure the coolant is fine. My 99 has 46k miles on it i had the coolant tested and it is A-OK not even close to needing change.
If you want to feel safe go ahead and change it. I really think it is unecessary though.
I'm sure the coolant is fine. My 99 has 46k miles on it i had the coolant tested and it is A-OK not even close to needing change.
If you want to feel safe go ahead and change it. I really think it is unecessary though.
Instructor
Joined: Jun 2004
Posts: 218
Likes: 0
From: Escondido CA
Originally Posted by robertpel9
I'm sure the coolant is fine. My 99 has 46k miles on it i had the coolant tested and it is A-OK not even close to needing change.
also, if you don't test the coolant, then use the recommended service interval. u can't rely upon a visual inspection.
Burning Brakes
Joined: Sep 2003
Posts: 1,085
Likes: 0
From: Broken Arrow OK
Changed coolant in my 99 last Saturday. Old coolant looked absolutely perfect. Looked like freshly made Cool Aid. Never seen coolant looking this good after 5 years and 33K miles. Still, I think it is good insurance and the cost is minimal. Only problem was that it took forever to drain. Filling was easy.
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Le Mans Master
Joined: Jul 2002
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From: Nevada and Florida
Originally Posted by robertpel9
Lots of cheap insurace floats around the forum LOL perhaps we should go work for Geico.
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I just changed mine in my '00 about three months ago (car was 4 1/2 years old with 24K miles). Manual says 5 years of 100K. I would go ahead and change it. Cheap insurance.
Team Owner
Joined: Sep 2001
Posts: 23,283
Likes: 906
From: Lake Elsinore, CA
I would use the time-elapsed spec for these cars since most of us will never see the kind of mileage rating the coolant has. Here's the procedure for those who don't have the manual.
Draining and Filling Cooling System
Caution
With a pressurized cooling system, the coolant temperature in the radiator can be considerably higher than the boiling point of the solution at atmospheric pressure. Removal of the surge tank cap, while the cooling system is hot and under high pressure, causes the solution to boil instantaneously with explosive force. This will cause the solution to spew out over the engine, the fenders, and the person removing the cap. Serious bodily injury may result.
Important
If the procedure below is not followed a low or high coolant level condition and/or vehicle damage could result.
1) Park the vehicle on a level surface.
2) Remove the surge tank cap.
3)Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
4) Place a drain pan under the drain fowl.
5) Open the radiator drain fowl.
6) Allow the cooling system to drain completely.
7) Inspect the engine coolant for the following:
Discolored -- follow the flush procedure below.
Normal in appearance -- continue with the next step.
Notice
When adding coolant, use DEX-COOL® coolant. If silicated coolant is added to the system, premature engine, heater core or radiator corrosion may result. In addition, the engine coolant will require change sooner-at 50 000 km (30,000 mi) or 24 months.
8) Close the radiator drain fowl. Tighten.
Tighten the radiator drain fowl to 2 N·m (18 lb in).
9) Fill the cooling system through the surge tank.
10) Fill the cooling system with a 50/50 mixture of DEX-COOL® coolant and deionized water.
11) Start the engine.
12) Allow the engine to idle for 1 minute.
13) Install surge tank cap.
14) Cycle the engine RPMs from idle to 3000 in 30 second intervals until the coolant temperature reaches 99°C (210°F).
15)Shut off the engine.
16) Remove the surge tank cap.
17) Start the engine.
18) Allow the engine to Idle for 1 minute. Fill the surge tank to 12.7 mm (0.5 in) above the COLD FULL mark on the surge tank.
19) Install the surge tank cap.
20) Cycle the engine RPMs from idle to 3000 in 30 second intervals until the coolant reaches 99°C (210°F).
21) Shut off the engine.
22) Remove the surge tank cap.
23) Top off the coolant as necessary, 12.7 mm (0.5 in) above FULL COLD mark on the surge tank.
24) Rinse away any excess coolant from the engine and the engine compartment.
25) Inspect the concentration of the engine coolant.
26) Install the surge tank cap.
Draining and Filling Cooling System
Caution
With a pressurized cooling system, the coolant temperature in the radiator can be considerably higher than the boiling point of the solution at atmospheric pressure. Removal of the surge tank cap, while the cooling system is hot and under high pressure, causes the solution to boil instantaneously with explosive force. This will cause the solution to spew out over the engine, the fenders, and the person removing the cap. Serious bodily injury may result.
Important
If the procedure below is not followed a low or high coolant level condition and/or vehicle damage could result.
1) Park the vehicle on a level surface.
2) Remove the surge tank cap.
3)Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
4) Place a drain pan under the drain fowl.
5) Open the radiator drain fowl.
6) Allow the cooling system to drain completely.
7) Inspect the engine coolant for the following:
Discolored -- follow the flush procedure below.
Normal in appearance -- continue with the next step.
Notice
When adding coolant, use DEX-COOL® coolant. If silicated coolant is added to the system, premature engine, heater core or radiator corrosion may result. In addition, the engine coolant will require change sooner-at 50 000 km (30,000 mi) or 24 months.
8) Close the radiator drain fowl. Tighten.
Tighten the radiator drain fowl to 2 N·m (18 lb in).
9) Fill the cooling system through the surge tank.
10) Fill the cooling system with a 50/50 mixture of DEX-COOL® coolant and deionized water.
11) Start the engine.
12) Allow the engine to idle for 1 minute.
13) Install surge tank cap.
14) Cycle the engine RPMs from idle to 3000 in 30 second intervals until the coolant temperature reaches 99°C (210°F).
15)Shut off the engine.
16) Remove the surge tank cap.
17) Start the engine.
18) Allow the engine to Idle for 1 minute. Fill the surge tank to 12.7 mm (0.5 in) above the COLD FULL mark on the surge tank.
19) Install the surge tank cap.
20) Cycle the engine RPMs from idle to 3000 in 30 second intervals until the coolant reaches 99°C (210°F).
21) Shut off the engine.
22) Remove the surge tank cap.
23) Top off the coolant as necessary, 12.7 mm (0.5 in) above FULL COLD mark on the surge tank.
24) Rinse away any excess coolant from the engine and the engine compartment.
25) Inspect the concentration of the engine coolant.
26) Install the surge tank cap.
Instructor
Joined: Jul 2003
Posts: 194
Likes: 0
From: Torrington CT
.... "drain fowl".... that is too much... 
By the way, how much did you get out using this technique? Did you start with the engine warm? I think I got out only about 2/3 of the total capacity....
L
By the way, how much did you get out using this technique? Did you start with the engine warm? I think I got out only about 2/3 of the total capacity....
L
Team Owner
Joined: May 2001
Posts: 36,836
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
Originally Posted by tipcapman
.... "drain fowl".... that is too much...
By the way, how much did you get out using this technique? Did you start with the engine warm? I think I got out only about 2/3 of the total capacity....
L
By the way, how much did you get out using this technique? Did you start with the engine warm? I think I got out only about 2/3 of the total capacity....
L
Damn those little computer conversions. Hey Ed, next time try drain-****.
Robert
BTW, I used distilled water for mine on the refill.
Last edited by LoneStarFRC; Aug 6, 2004 at 10:29 PM.
Team Owner
Joined: Sep 2001
Posts: 23,283
Likes: 906
From: Lake Elsinore, CA
Originally Posted by LoneStarFRC
Damn those little computer conversions. Hey Ed, next time try drain-****.
BTW, I used distilled water for mine on the refill.
I leave it like that because everyone gets a kick out of it when I post it. And, yes, distilled water is best. 
Le Mans Master
Joined: May 2002
Posts: 6,170
Likes: 1
From: Kona Hawaii
St. Jude Donor '03-'04-'05
Originally Posted by my6thvette
Changed coolant in my 99 last Saturday. Old coolant looked absolutely perfect. Looked like freshly made Cool Aid. Never seen coolant looking this good after 5 years and 33K miles. Still, I think it is good insurance and the cost is minimal. Only problem was that it took forever to drain. Filling was easy.
had my 98 done last week, 34K and the tech said it looked perfect......ah well its done now
Team Owner
Joined: May 2001
Posts: 25,058
Likes: 1,265
From: Virginia
St. Jude Donor '11
Originally Posted by ROJ#79
Does any body have any views on when to change the Dex Cool Coolant in a C-5?
The manual says 5 years or 150,000 miles.
I have only 15,000 on my 99 and it looks good.
Just wondering if I should change it or not!
The manual says 5 years or 150,000 miles.
I have only 15,000 on my 99 and it looks good.
Just wondering if I should change it or not!