i pulled the surge tank and there appears to be a sensor on the bottom and it very loose in there and could possibly be leaking there anyone ever had that issue?

 

subd

 

See attached. Worth a try.

 

thanks ill give it a shot

 

Have you recently drained the coolant? If so, then purging the system makes perfect sense.

If the truck was operating normally then starting pushing coolant from the inboard side of the tank to the outboard side, it's probably not good news.

A leak at the coolant level sensor, although entirely possible, would not explain the outboard (non pressure) side of the tank being full.

If you fill the inboard side of the tank, put the cap on and start the engine, do you see a stream of tiny bubbles entering that side of the tank?

 

Have you recently drained the coolant? If so, then purging the system makes perfect sense.

If the truck was operating normally then starting pushing coolant from the inboard side of the tank to the outboard side, it's probably not good news.

A leak at the coolant level sensor, although entirely possible, would not explain the outboard (non pressure) side of the tank being full.

If you fill the inboard side of the tank, put the cap on and start the engine, do you see a stream of tiny bubbles entering that side of the tank?

ok so yes i had the thermostat chanegd a few months back. i used the truck since then but havent really had any issues it was also alot colder, dont know if that had anything to do with it.

so here is where i am at i ended up pulling and draining the surge tank.(Both sides) refilled following instructions above and ran truck various times and idled. everything seemed ok. after i let it cool off i hooked up a trailer and went for a spin no low coolant light comes on but i do notice on the outer tank there is bubbles coming from the bottom?
i dont remeber seeing any piping going in the bottom. Does the outer(non pressured) side have an inlet inlet at the bottom or is it only the drip from the top . also i noticed after the truck has been run for a 20 mins with a trailer that the pressure side drops quite a bit... let me know what u think thanks again

 

I haven't cut one of those coolant tanks apart but I believe the only passage from the pressure side to the non pressure side is at the top.

Unfortunately, if it's still pushing fluid from the pressure side, especially under heavier engine loading, sounds to me like a head gasket is starting to go. That's how it starts.

But I'm open to any other opinions if there's something we're missing here.

 

i agree on that with the pushing the coolant over to non pressure side but it definetly might be an inexpensive fix for me to swap out the surge tank and hope that is the problem. I was thinking maybe when the thermostats were done that it wasnt filled properly after and thats why the coolant was pushed over to non pressure side but i dont know why else bubbles would be coming up on that side unless there was a small air leak which essentially destroy the pressure system of the tank. thanks fro your help so far if anyone else has any suggestions please let me know

 

I just had my head gaskets done on my 14. Bubbles, hard upper rad hose and spitting coolant out the tank after driving. Gasket had slightly lifted next to cylinder 4. Also had a small coolant leak at the oil filter housing gasket.

 

I have heard of some surge tanks leaking another way to check head gasket is to let truck sit overnight the next morning open hood and squeeze top radiator hose if it is firm then its a head gasket

 

I have heard of some surge tanks leaking another way to check head gasket is to let truck sit overnight the next morning open hood and squeeze top radiator hose if it is firm then its a head gasket

Thankfully i checked that this morning and hose is not hard, i can squeeze it flat

 

I have a 2014 3500hd. Kept getting the low coolant warning. Happened most when it was cold outside and started the truck.
had a very slight coolant smell on the right front corner of the truck.

Chevy service dept couldn’t find the problem until they bumped up the coolant system pressure test from 20lbs to 30lbs. Resulted in finding a pinhole leak near the bottom of the radiator.

replaced radiator and lower hose assembly. No more warnings.