I just bought a 08 Hummer H3 3.7L it runs and drives great! The only thing that worries me is the tempature gauge needle is a little over half way at idle but once I give it gas a lowers back down close to halfway but when its in park or idle its a little over halfway i dont know if this is normal or is there something causing it? Lmk if any if you have a similar problem! Thanks!

 

the forum is littered with the same question you are asking. search the forum. there have been many threads started over this same inquiry even in the last few weeks.

 

What is a little over half way and close to halfway?
You just bought it:
check the coolant level, and condition/mix of the coolant.
Should be bright orange & 50/50 mix.
Also, use a scanner to check temp.

This is the highest my gauge goes no matter what the ambient temp is nor where I drive:

 

I would say my needle is about a centimeter further then where yours is at and iv checked the coolant everything looks good and I put the scan tool on it and it reads 202 degrees

 

202°F is in the safe zone.
GM has determined there are calibration concerns with this gauge and no repairs should be considered at this time.

 

But once i turn the vehicle off and just turn the key over to turn the cluster on the temp needle rises to the last needle before the needle where it says hot

 

Welcome to HF. I MOVED this for you as all H3 questions go in the H3 section.

You do not have a problem other than a touch of paranoia.

Do a search. The dash temp gauge is like an idiot light with a needle, anything 3/4 or below is NORMAL.

Take a look at this thread so you understand it doesn't matter what the temp gauge shows after you shut off the engine..... auto cooling 101. 2006 Hummer H3 over heating to 3/4 when parked.

 

Your right today I actually used my temp gun and it reads 178 degrees so either the cluster or sensor ia bad

 

Temp gun? Like Infrared Temp sensor? Not going to tell you what coolant temp is, only surface temp of whatever you pointed it at, not what is inside.

The easy & accurate way to confirm actual temp is a scanner through the OBDII port.

 

That's correct Doc, surface temp is not accurate. Using infrared is only to find a huge temp variance in the coolant system to determine a flow issue. I just checked at idle with the front grill covered. @201°F on the scanner, I used an infrared gun and checked the upper/lower radiator hose, upper radiator tank, heater hoses, etc,,, and only got readings in the 160's°F-170's°F.