I have about 100k miles and my coolant appears to be leaking out of the small upper hose right under the radiator cap. The upper radiator hose gets very hot and the lower hose is cold. I’ve already replaced the thermostat. When I had the coolant out I was able run water through the large upper radiator house and out the bottom without an issue. Any idea what the problem would be?

 

So, really all you are talking about is a leak.

Simply replace the hose.

Unless you are talking about the little hose that routes coolant into the overflow reservoir. In that case, put a plastic tie-wrap or a clamp on it and maybe replace the radiator cap.

Is it overheating or anything, the Temp gage working normally, heater blowing hot air like it always did, etc.?

Welcome to Ranger-Forums!

 

Yes i think the only problem is a leak from the hose going to the radiator overflow tank. I do have a plastic clamp on it but it's still leaking. i know there's different type of caps... what kind am i supposed to buy? Also, is it normal that the lower hose is always cold?

Thanks for all your help!

 

You were able to run water through the upper hose, radiator, and out the lower hose and it flowed through freely?

I believe that hose is just a push on. See if you have enough slack to cut off about 1/2-3/4 inch off that end and then put it back on giving it a tighter fit. I'd also replace the radiator cap while your at it and then recheck for leaks. Keep an eye on you temp and ensure your getting hot air from the trucks heater.

 

Ok i just put on a brand new radiator cap and cut the small hose a little and re-inserted it with a clamp. Ran around the block and now it's leaking from another hose right below the coils and it's squirting on everything. The big radiator hose on top is very hot and the lower hose is cold. It's like there's just too much pressure on top... any ideas?

 

Are you talking about the heater hoses (ones going to the firewall)?

The lower rad hose will feel colder than the upper until the thermostat opens and circulates coolant.

 

yes it is one that goes to the firewall but its leaking right under the coils. Once the thermostat opens the lower hose should get hot or warm at least right? Mines stone cold even after a highway run...

 

You'll probably need to replace that hose as well as the other while your at it.

If the outside temp is cold enough the lower hose may not get very warm driving around.

Since it sounds like you replaced your coolant you may have trapped some air in the system as well.

Run the engine with the truck parked (preferably in a garage with the front of the truck higher than the rear if possible) letting it warm up. Vary the RPM between idle to 2000 from time to time watching the temp gauge (it may also overflow the recovery bottle and the temp my go up higher then normal until the thermostat opens, but keep it going until you feel the lower hose starting to get good and warm) (If the temp gauge starts to go full peg shut it down). Let it idle for a few more min. then shut it down. Make sure the recovery bottle is full. Let it sit until its cold. Check the recovery bottle and add if necessary. If its empty, take the Rad cap off and top off the system.

Add...make sure you have your heater temp set to full hot and in vent position while doing the above.