Is it ok to use these cleaners, and if so, what brands do you use?? I have a 2020 TB 5.3 v8 with 36K miles on it and havent used and fuel injector cleaner yet. Noticed my mpg went down and am thinking about using it.
The manual says not to, but using a decent brand sparingly should be okay. Try to use top tier and ethanol-free fuels whenever you can, that should also help clean things up while helping to maintain a clean engine.
Here's what my owners manual says. You can get the GM treatment from Amazon a lot less than the dealer.
Fuel Additives TOP TIER Detergent Gasoline is highly recommended for use with your vehicle. If your country does not have TOP TIER Detergent Gasoline, add ACDelco Fuel System Treatment Plus−Gasoline to the vehicle’s gasoline fuel tank at every oil change or 15 000 km (9,000 mi), whichever occurs first. TOP TIER Detergent Gasoline and ACDelco Fuel System Treatment Plus−Gasoline will help keep your vehicle’s engine fuel deposit free and performing optimally
Also remember we lose mpg when they switch over to winter blend fuels for emissions every winter… I lose about 1-2.5mpg every winter because of this… they switch our fuels every season from November- April to winter time fuels here in the Northeast..