Topping off coolant every few years.

Austin83 · July 27, 2014

2008 GMC Sierra 1500 with 57,000 miles. I haven't checked my actual coolant level in quite a long time. I usually glance over at it to make sure it's near the top. Today I added 8 ounces of 50/50 Dexcool and distilled water to bring it to the cold full line. I think I last topped it off three years ago. Is it normal to have to top off your coolant every few years? I don't have any known coolant leaks, and I change my own oil so I know my head gasket is just fine. I'm really more curious then concerned. Thanks.

kstruckcountry · July 27, 2014

Yeah it's normal, but it should really be changed every 3 years or so.

Austin83 · July 27, 2014

Thanks guys, I plan on changing the coolant next week. I have never done this on this truck so I want to confirm that I have the right procedure.

1. Pull the lower radiator hose and let the system drain, and reinstall the hose.

2. Refill with distilled water to the COLD level on the reservoir, and start the truck to heat it up and allow the water to circulate.

3. Pull the lower radiator hose again and drain the system, reinstall the hose and refill with 50/50 distilled water and Dexcool to the COLD level.

Do I need to keep the cap off of the reservoir during step 2 and 3 to bleed the system? Anything else that I missed or got wrong?

efritz · July 28, 2014

NO!!!! do not refill with 50/50 if you are flushing as you only get about 60% of the coolant out of the system at any given time, so you are adding 50/50 coolant to water. Not good. You will end up with something like 35% coolant which freezes around 0 degrees F. I see you are in TX but if you drive north, like here, and it gets below while you are here you will be a sad puppy. Refill with 70/30 (70% coolant) after water flushing and then you will end up around 50/50 or at least on the safer side of 50/50. I run 60/40 as it it gets to around 30 something below here sometimes in the winter and that's about the limit of 50/50 coolant.

white1500 · July 28, 2014

You can also buy premixed dexcool approved coolant and no t worry about your mixture.

Although to be honest I would just start planning for a cooling system overhaul to get it over with before you get real problems. New hoses, radiator, pump, thermostat, coolant, plus any other misc items you can think of.

MaverickZ71 · July 28, 2014

2008 GMC Sierra 1500 with 57,000 miles. I haven't checked my actual coolant level in quite a long time. I usually glance over at it to make sure it's near the top. Today I added 8 ounces of 50/50 Dexcool and distilled water to bring it to the cold full line. I think I last topped it off three years ago. Is it normal to have to top off your coolant every few years? I don't have any known coolant leaks, and I change my own oil so I know my head gasket is just fine. I'm really more curious then concerned. Thanks.

My '09 Silverado (5.3L) drinks up to a pint or two of Dexcool coolant mix per year (normal use, no towing.) I fill it back up to the "cold full" line in the coolant tank each fall with Prestone brand premixed 50/50 Dexcool/distilled water. This is the first vehicle I ever had with no apparent leaks and a little coolant disappears. At least it is not a very large amount and doesn't appear to get any worse. GM service manager said that is normal. (But then again, GM says 3-4 quarts of oil usage between changes is 'normal', too . . . ) Getting ready to drain and refill the coolant this fall as per the owner's manual maintenance schedule (it'll be 5 years old then, but nowhere near the 150K miles).

Austin83 · July 29, 2014

Thanks for the replies. I chose to get the dealership to flush the radiator. I considered the mess and hassle and chose to pay extra and the truck was done in 45 minutes.

Austin83 · July 29, 2014

Does anyone here know how they service the coolant at the dealership? I can't find any evidence that they drained anything (no mess, lower hose looks untouched, etc.)

txab · July 29, 2014

They use a recirculating machine to capture the old coolant and add the new coolant. Generally not dumping on it the floor nowadays

Austin83 · July 29, 2014

They use a recirculating machine to capture the old coolant and add the new coolant. Generally not dumping on it the floor nowadays

thanks, makes sense. Looks like they just used the smaller hose from the radiator to the reservoir.

ram1067 · July 30, 2014

My '09 Silverado (5.3L) drinks up to a pint or two of Dexcool coolant mix per year (normal use, no towing.) I fill it back up to the "cold full" line in the coolant tank each fall with Prestone brand premixed 50/50 Dexcool/distilled water. This is the first vehicle I ever had with no apparent leaks and a little coolant disappears. At least it is not a very large amount and doesn't appear to get any worse. GM service manager said that is normal. (But then again, GM says 3-4 quarts of oil usage between changes is 'normal', too . . . ) Getting ready to drain and refill the coolant this fall as per the owner's manual maintenance schedule (it'll be 5 years old then, but nowhere near the 150K miles).

so you add water to the 50/50 premix?

MaverickZ71 · July 30, 2014

so you add water to the 50/50 premix?

Negative. I use Prestone Dexcool mix--already mixed 50% Dexcool equivalent and 50% distilled water in a one-gallon jug. I do not add anything (water, Bars Leak, Water Wetter, pee, or Bud Light, etc.) additional to the system.

ram1067 · July 30, 2014

Negative. I use Prestone Dexcool mix--already mixed 50% Dexcool equivalent and 50% distilled water in a one-gallon jug. I do not add anything (water, Bars Leak, Water Wetter, pee, or Bud Light, etc.) additional to the system.

now that's some funny $hit