Does anyone know the procedure for removing air from surge tank or coolant system. Took my truck to the dealer they said no leaks just needed to remove air from system. Kept my truck two days and several days later message returned.

I just filled mine up to the top

Took mine in for the same message and they added a little coolant and then tried to charge me for shop supplies (antifreeze) and time! Told them I didn't think that was right as the truck wasn't even due for it's first oil change yet. They finally figured out there was a TSB for it and "waived" the charges.

Didn't require any "burping".

The system is designed to self evacuate air over time but depending upon how much was in the system it may take more than one fill. I have been keeping an eye on mine but so far the coolant level hasn't changed since I picked it up new with less than 20 miles on it.

Fill procedure is in the manual, but as above if it's only down a little just add some and it should self correct after a couple of heat/cool cycles.

Common to have to add a little to a new one.



What year is the truck?
How many miles/how long in service?

So how much coolant is to much? Can I fill the overflow reservoir basically all the way to the top, or is that gonna cause a fountain under the hood? I do have it slightly above the two arrows, but im wondering if i can add more, I want as much as possible.

Check for coolant leaks. On mine we found a cracked hose that slowly drained the coolant from the system. The coolant return hose clamp was overtightened and the hose split. This hose is right against the firewall next to the AC lines. I had the hose replaced and the coolant system flushed by the dealer.

I had the same issue and the service manager at my dealer said that you top off the reservoir with the surge tank cap off and it will allow the air to bleed out and let the other chamber of the tank to fill. that worked for me.

What TSB is this? I just got the "low coolant" message this morning on initial start after the truck had sat for 3 full days. I have a 2017 GMC 2500.

Just a quick look and I found this https://www.duramaxforum.com/forum/l...l#post11062898 posted in the L5P TSB (service bulletins, recalls, updates) section...