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GMC Sierra 1500, Truck
#21 of 79 1989 K1500 Thermostat opening late?
Mar 15, 2007 (4:07 am)
I own an 89 K1500 Pickup. Originally, the radiator was leaking, so we replaced it. In the process, the seal for the waterpump went bad, so we replaced that too.
Unfortunately, now most of the cooling system has been replaced, but my truck still overheats. I have replaced the thermostat 5 times, thinking it was bad as it was opening late.
I do know that there were two types of radiator stop leak poured into the system prior to replacing the radiator.
On my way to work in the morning, it is ~32 degrees F. My truck ussually overhearts quickly if I am driving at ~50-60 mph. However, if I take sideroads, I can do 40 mph and the truck will start to climb up to ~210 degrees and if I pull off and let it idle, the thermostat will eventually open and the system will be fine after that.
This typically does not happen on my way home from work no matter how fast I drive. The temps going home are warmer ~40-50.
I just replaced my Radiator cap yesterday, thinking that might be the problem - it wasnt. Then I flushed the radiator - that didn't help either.
If I let the car idle until the thermostat opens every morning, it drives without a problem.
I just can't figure this one out. Is my coolant system clogged or gummed up? Is the coolant mixture bad? I know I used 50/50 premix to fill my radiator last night after I drained it and flushed it.
I have done everything just shy of having my whole system flushed... that was going to be my next step.
#22 of 79 Slow coolant loss (head replacement) update
Jun 07, 2007 (3:11 pm)
I had gradual coolant loss over time, it was not from the water pump (replaced), intake manifolds because they are dry. I had paid $900 for an ext warranty when I bought my Z71 back in 2003 with a 5.3 reg cab. I have to say it has paid for itself, both of the heads were replaced due to a porosity crack in the head. After the rocker covers were off, there was plenty of dexcool that had gelled in the covers. The warranty paid for all of it for a total of around $2800 labor & heads, plus a electrical part.
So if anyone has slow coolant loss be-aware of the symptoms and you can find out by pulling a rocker cover off. If you got coolant then you have to have new heads. I have 99,300 miles on the truck and the warranty runs out at 100,000 I will most likely purchase an extension since it has more than paid for itself.
Good info to know.
#23 of 79 Low Coolant Light Keeps Coming On. HELP!!
Sep 20, 2007 (2:01 pm)
#24 of 79 Low Coolant Light Keeps Coming On. HELP!!
Sep 20, 2007 (2:01 pm)
I have a 2002 Chevrolet 2500HD crew cab. My low coolant light keeps coming on , I put coolant in each time but I have no idea why it is doing this. I just added coolant on Sept 1st and here it is 19 days later and the light is on again. What should I look into doing first? What can be causing this? My temp gauge is fine it never goes up when the light comes on. Any suggestions? Thanks!
#25 of 79 Re: Low Coolant Light Keeps Coming On. HELP!! [jandk4211]
Oct 26, 2007 (9:37 am)
Hope you've found the solution by now. I've got the same problem in the same model with 6.0 liter engine. Went and checked with a trusted mechanic this morning expecting to spend BUCKS. He said, "GM is aware of this problem. Go by the Chevrolet dealership, and pick up a package of 5 tablets. Put them into your cooling system and drive it. The tablets will seal the tiny cracks in your heads and gaskets." He claims it works! The dealership charged me $5.95 for the parts in a GM package, and seemed very aware of the problem. So if you haven't gotten a solution by now, don't be too scared....hope this works for both of us. My truck will see HEAVY usage from now until the end of february.
#26 of 79 Re: 1989 K1500 Thermostat opening late? [chosos]
Oct 26, 2007 (9:55 am)
I don't know if this will help at all but I have two chev trucks that would not keep a consistent water temp. It would fluxuate up and down all the time I was driving it and when idling my heater went cold. I did much of the same repair with no result and then before a trip to Fla I replaced my serpentine belt and the temp has been steady since. The pulley that drives the water pump and fan is on the flat side of the belt and not the ribbed side so it seems that all these years the belt has been slipping over that pulley causing the water pump to run slower than it should. If you don't want to replace the belt you can also try a belt dressing that can be sprayed on for extra traction
#27 of 79 Re: Temperature fluctuating [bbydolly13]
Oct 26, 2007 (9:58 am)
I don't know if this will help at all but I have two chev trucks that would not keep a consistent water temp. It would fluctuate up and down all the time I was driving it and when idling my heater went cold. I did much of the same repair with no result and then before a trip to Fla I replaced my serpentine belt and the temp has been steady since. The pulley that drives the water pump and fan is on the flat side of the belt and not the ribbed side so it seems that all these years the belt has been slipping over that pulley causing the water pump to run slower than it should. If you don't want to replace the belt you can also try a belt dressing that can be sprayed on for extra traction
#28 of 79 2004 chevy silverado coolant leak
Nov 11, 2007 (8:20 pm)
I have a 2004 silverado. 5.3 engine with about 87000 miles. I noticed a coolant leak on the right side of the engine that appears to be a head gasket. Has there been any recalls for this? How much should I expect this to cost?
#29 of 79 Re: Low Coolant Light Keeps Coming On. HELP!! [garnold]
Nov 12, 2007 (8:13 pm)
Thanks for the tip!!! I was planning on taking my truck to the dealer in the morning. It does seems like a patch instead of a fix....but I guess if they are having trouble with crazing of the casting or porosity it should work. Too bad the warranty is expired!
#30 of 79 Gmc Sierra radiator
Dec 07, 2007 (11:25 am)
my radiator cracked and i found one at a junk yard but it has a small hose right below the cap that my truck doesn't have can i cap it off? it has all the other hoses and hardlines that my truck has