This is with my 86k mile 2003 Dakota 3.9L RWD atx.

I have to add coolant maybe once every 6 weeks or so. I add it since the dipstick comes up dry.

I do not notice any leaks when my truck is parked outside my apartment (tough with crushed stone) nor when I am parked all day at work (easier with the asphalt). The truck never runs warm. I have not done a crazy inspection, but a brief visual shows no leaks either. The floor is not wet on the inside either.

With my Neon I would think headgasket, but the last couple times I changed my oil it looked ok. I will be changing my oil again this weekend, so I'll check again.

Any ideas??

 

I believe they make a dye for the coolant as well. I would recommend using it and then tracing it with a black light. This is the easiest way to tracka leak, rather than going over every spot it could be leaking from.



.02

 

That sounds likea small leak. I'd start with the radiator cap. A leaking cap can allow coolant to evaporate off, or even leak when under pressure. A new cap is cheap, and is good insurance anyway at this age, even if yours appears to be holding.

In addition to the dye (a good idea), have the cooling system pressure-checked. It's apparently a leak that may only happen when the engine is running and the system is fully pressurized.

 

Good idea on the dye. I forgot about that.

Radiator cap is a good idea too.

This is why I asked, the little things are the ones that you forget!

 

You can rent a Coolant Pressure Tester at Auto Zone, pump it up to 16lb's I believe the Dakota is (check on the radiator cap) and watch the gauge. If it's slowly dropping then your fluid is going somewhere, time to look for where its streaming out.

 

Definetly pressure test. Its so easy to to do. You can sit there and watch where it is leaking from, it is not leaking at all then its probably just your cap.

 

If you can't find a leak, I would be checking your tranny fluid... Could be serious. Also check the oil again. That would make me paranoid...

 

I never thought of the tranny fluid. But when I have checked it in the recent past it has looked ok and been to a proper level. I just never thought to check it for that reason, but I always check it.

I just ordered a rad cap and I'll do the pressure check.

My truck is getting old =(

 

lol, not even mine is a 1997...

But if it is in the tranny you will probably need a rebuild or atleast a flush. Than I would buy a BYpass cooler, and keep it separate from the radiator to avoid contamination again.

 

Old?? Nah, your truck is fine. Mine's a '97 with 168,000 miles. Yours is barely broken in; not even 100k miles yet.