Hello 99 dodge ram cummins diesel . I have a coolant leak at the firewall. I am curious if it is the heater core or the hoses. I still have heat (doesn't blow hard) and no wetness in the passenger floor. I lost anti freeze but after driving a while it quit losing any more. Unfortunately i think the leak is behind the firewall so i guess the dash will need to be removed anyway. However any tips or advise to help troubleshoot will be very much appreciated. I had the heater core replaced maybe 5 years ago but i hear its pretty common on these dodges.

 

Where was it dripping from? If the leak was behind the firewall, it wouldn't have any where else to go, aside from the floor of the truck.

 

I have have a similar issue, and like yours it quit, just waiting for it to get worse. I don't think anyone likes to pull a dash, sometimes small leaks tend to clog themselves up. I would suggest some brand of coolant leak repair that you can pour into the system.

 

The coolant is puddling on the ground but i cant figure out exactly the source sorry. Seems near the firewall on passenger side next to accumulator. I will fill up the reservoir and see if i can trace the source. On my errands yesterday each time i stopped it continued to leak coolant. I think it stopped but will need refilled and likely will leak again.
I sure wish it was an obvious hose as the shop is never cheap.

 

The heater hoses are more in the middle. I suppose it could be running down. Maybe check the hose for a leak first.

 

Thanks 2bit. Going to try again to look where the leak is coming from. I looked at the heater hoses and anything i could see going through the firewall on the passenger side, just unable to see any obvious leak from any hose in front of firewall.

 

There is UV test dye for cooling systems. Get a test kit with the light and glasses (do NOT use it without the glasses) and see where the dye shows up. You might just have a bad clamp on one heater hose.

 

Another easy suggestion would be to use a small mirror, even the parts houses have them.

 

Thanks. I ran motor and again same leakage dripping down from firewall just behind that canister. I see the heater hoses and those stainless hoses and quite why that canister is getting iced over when im calling for heat i dont know. you may see coolant on that strut down there.

 

I think you are running the AC and seeing the drain for the AC