I get the no brained part. Just don’t know how finicky the H3 is. I drove it last night and the temp stayed right around 218 -222.

 

218-222 is HIGH. Did you replace the T-stat?

 

Distillation effectively removes inorganic compounds such as metals (lead), nitrate, and other nuisance particles such as iron and hardness from a contaminated water supply. The boiling process also kills microorganisms such as bacteria and some viruses.
AKA: 7732-18-5

 

Not yet. I have to order it. Won't be here until Monday.

 

I just noticed the thermostat I purchased is 180 and not 185. Will that matter? I thought it was 185 degrees.

 

190°F is oem in the 5.3. You can go lower in AZ.

 

So I will install the 180 one I have on order then. I also have a new radiator cap coming as well. Not sure if I need it but good to have it as a spare. Thank you.

 

Correct.... I use distilled because tap water (city water systems) use chlorine and fluoride, and some is hard with calcium and other minerals you do not want in your coolant.

 

High, yes. Too high, no. It's not uncommon in AZ, NV, parts of SoCal, Cypress, Greece, and a bunch of the middle east per many customers who have reported actual coolant temps in association with their questions. You are going to get heat creep when it is super hot outside.

 

Super hot is almost all summer long.