06/11/2026
Hemi 5.7L cooling system question β what should I expect? π€π§
I have a 2015 Charger R/T with 138k miles. The water pump was replaced around 97k miles, and it's been running fine ever since.
A few weeks ago, I noticed a stain on the engine that appears to be coming from the hose connected to the water pump. Every couple of weeks, I'd also see a small amount of steam from under the hood shortly after startup, but it would disappear quickly.
The main reason I finally brought it to a shop was because the coolant had turned brown and looked sludgy. I didn't want to keep driving it and risk a major failure.
The shop told me they suspect someone added stop-leak to the cooling system at some point, which may explain the brown coolant. They also said that when they opened the radiator drain, nothing came out, which definitely got my attention.
Oddly enough, the car has never overheated. I've been monitoring coolant temps and they usually stay between 190Β°F and 210Β°F, which I thought was normal.
Based on these photos and symptoms, what do you think I'm likely to hear when the shop calls back? Is this something that can potentially be fixed with a thorough cooling system flush and clearing a blockage, or am I probably looking at replacing major components like the radiator, water pump, thermostat, or other parts?
The shop has a good reputation, and my friend's dad works there and has been sending me photo updates throughout the inspection. For once, I actually feel like I'm dealing with people I can trust.
Curious what everyone thinks.