I have a 2005 chevy duramax that does not heat up properly. In cooler weather , it takes 10-15 minutes to get the heater to work. I want to change the thermostat, but I.m not sure where it is located. I assume its where the radiator hose connects on top of the motor, but would like an rexploded view before i start unscrewing things. Any help would be appreciated. Tom K

My thought was no shim kit fitted which makes the pads tilt, others may disagree and have other ideas.

https://www.google.com/search?q=2007+Chevy+Duramax+Front+brake+locks+up+in+cold+weather

..

Coolant level? Is water pump working? Is thermostat stuck? Are cooling fans running? Do radiator hoses and heater hoses feel hot? You can either provide this information or take your vehicle to a qualified professional and have it properly diagnosed and repaired.

i havent seen the duramax tucks of this year model inside under the hood but it would seem that is possible

more than likely there is a leak in heater coil. check your front passenger floor board to see if it is wet. if so the coil will need to be replaced. also take the two heater hoses off of the back firewall under windshield and run water thru the two pipes and try to flush it out.

may have air trapped in it still or thermostat is not working properly..

Its either low on coolant or the heater control valve is faulty.

could be the thermostat if it was just stating to go bad,could also be a vacume problem not letting the door for the ac/heat close all the way for a few min.and if its really cold out like below 35,then its going to take longer to warm up,my jeep takes like around 20 min at idle to warm up.yours could be a case of over cooling in cold weather too ie(electric fans on before it warms up)that would be the thermostatic sensor.

Has anybody checked for the proper coolant level when hot? MAKE sure u CHECK THE WATER PUMP OPERATION!

I am told the glow plugs heat up in "firing" order, also the Duramax uses a intake air heater to warm the air on cold starts.

There a heater control valves behind the dash which is either broken or have gotten stuck. The valve behind the dash act as on and off switch as as you would turn your faucet on and off. they tend to get stuck due to heat. The valve basically allowed hot antifreeze water to flow though the heater core giving you heat. when the valve broken or stuck open, the hot antifreeze will continuous flow to the heater core, therefore is the reason why you get constant heat. It a nightmare to fix, you will have to take the dash apart to get to it. the part run somewhere in 40 bucks. if your not mechanical incline, my suggestion would be the next time you get oil change from your local chevy dealership is to ask around those GM mechanic (Do not ask the Manager) and see who does side work; negoiate with him this way you will save big buck on dealership shop hours. Have only authorize GM to do the repair, not your local repairshop. Tearing into any automotive dashboard its every mechanics nightmare. Good luck!!!