shooterrdy

Got an 08 LS3I drained coolant put oriely brand thermostat in and now runs warm at idle 210 - 216 idleing 205 down the road. Any ideas drove it abour 100 mile now and problem presist?

jonjoy

Stock thermostat should run about 190 at speed on the highway, did recheck the system if you did a drain and fill it should burp for lack of a better term then you can add more water

Spaceme1117

Your car is not overheating but it should be running closer to 195-200 when going down the road.

Most likely you have a bit of debri in the front of the radiator. You could also get under the front of the car to check it. More than likely there is a good bit of leaves, dirt, etc. that is blocking some of the radiator.

rc51racer

05 Z51 6 Speed here. I recently replaced radiator and flushed system, all was good. A few days later my water pump took a dive. While changing WP I replaced OEM thermostat. OE thermostat internals were destroyed. I did purge air out of system by removing the throttle body hose and using a small amount of compressed air to blow toward radiator side and allow coolant to flow from steel line. Took a few times but worked well.
My temps on highway are 196-199°
Funny thing I noticed is the harder I run the engine on the highway the cooler it runs.

grcor

Make sure you have this flexible black cover is in place. You can remove it to clean out leaves and other trash that might be blocking the oil cooler and radiator and then put it back.

compyelc4

I have an '07 LS2 that runs exactly the same temp as yours. I don't see a problem.

shooterrdy

I think I forgot to index the thermostat correctly gonna put the stock one back in as it looked like new anyway.