Mechanics

ENGINE RUNS 160 DEGREES

1995 GMC Truck

Engine Cooling problem
1995 GMC Truck V8 Two Wheel Drive Automatic 189000 miles

I changed my radiator in my GMC Truck, 350 engines and afterwards the temperature will not get above 160 degrees. It is affecting my engine performance and gas mileage. I have changed my t-stat and temperature sensing unit and it still runs at 160 degrees. I made sure the t-stat was a 195 degree as well. When I replaced the radiator it appeared to be exactly the same. Everything fit perfect, the thickness, width etc. Was the same. Is it possible I got the wrong radiator?

Oh, I have also noticed problems with my transmission not wanting to shift since the cooling problem started and the engine idles up when this happens. After I stop the engine and wait a while, it runs normal. I may do this once every couple of weeks.

Any help would be greatly appreciated.
Thanks,

Todd
Avatar
Toshgaal
March 19, 2010.



The replacement radiator, was it new, Oem replacement? I'd have to double check the engine temp, your gage may not work correctly. Is there circulation through the radiator? Do the heater hoses, get hot? Any applicable trouble codes?

JDL
Mar 19, 2010.
No, it was not OEM. I checked the temperature of the engine where the thermostat house is with an infrared thermometer and it read around 170 degrees. I noticed the radiator cap does not seem to be getting hot at all, even after I have driven for 1/2 hour. The radiator hose registered around 140 degrees going leaving the radiator. I am going to see if any trouble codes show up this weekend.

Tiny
Toshgaal
Mar 19, 2010.
Sorry, it was a new radiator, but not from the dealer.

Tiny
Toshgaal
Mar 19, 2010.
Is the radiator cap new? What is the pressure reading on the cap?

JDL
Mar 19, 2010.
No, the radiator cap is not new. In fact, it is probably 8 to 10 years old. I do know that there is pressure on the hoses and coolant pulls into the radiator from the overflow tank.

Tiny
Toshgaal
Mar 19, 2010.