Hi all, here is my problem. 02 cclb 2wd dually, about 3-4 months the low coolant light flipped on, so we topped it off and all was good. Then today the low light came back on after about 7,000 miles. No signs of pressuring the coolant tank or sut. No coolant smells from the exhaust no white smoke either. Truck has about 150,000 miles on it. Should we have a pressure test done on the coolant system and or any sysptoms to look for?

Hi all, here is my problem. 02 cclb 2wd dually, about 3-4 months the low coolant light flipped on, so we topped it off and all was good. Then today the low light came back on after about 7,000 miles. No signs of pressuring the coolant tank or sut. No coolant smells from the exhaust no white smoke either. Truck has about 150,000 miles on it. Should we have a pressure test done on the coolant system and or any sysptoms to look for?


Definitly have a pressure test and check all the hoses and look for coolant on the underneath the truck. There is a couple of things that like to leak after a while. Especially the hose going to the turbo. Also could be the water pump. Just check the easy things first.

Go look for the weep hole in the waterpump, it can SLOOOW Leak and evaporate and you would never see any indication except for when the light comes on.

Also if you pressure test it, you still need to find the leak, so alittle time now looking for indication of a leak will save you the diagnostic fee later.

With 150K, I am betting on the waterpump.

Mine has done the same thing for the 5 years I've had it, and mostly during the summer. Please post your results!

I have 143K on my truck and I am having the water pump replaced on monday. Coolant was leaking out of it pretty good and I am hoping that is the only problem and its no the head gasket.

are you gaining oil ?

yes check your oil if its a white carmel ur getn coolant in ur oil from some where if u pull ur stick and its white do not run it all all u will toast ur engine if u didnt already. I wish gm had installed the water pump assembly exturnally to ovoid this problem and they are a hore to change as well

Sorry guys no new results. No milk in the oil, and or gaining any. You cant even smell it but the light hasn't came on again. I will check the weep hole next time im around the truck. What do you mean by internal water pump WTF???? So what all is required to replace one? We had one other problem with this truck it was the coolant recovery tank cap wasn't venting and sucking the upper hose shut are these issues related? Oh and no visual sign of leakage that I could see.

ISthe upper radiator hose supposed to be sucked in When you turn the truck off? Mine always is, is this a problem?

ISthe upper radiator hose supposed to be sucked in When you turn the truck off? Mine always is, is this a problem?
My truck does this too. When I was looking to buy one, about 85-90% of them that we saw sucked the upper radiator hose flat when they cooled.

From what I have read, if your hose remains/gets hard after sitting, it could be a sign of a bad headgasket.

Anyone have a definitive answer: is the upper hose supposed to remain round (i.e. are our rad. caps bad), or is it OK to have the hose suck flat when sitting??

Remain round and flexible after cooling. Level high in tank when hot and falls a bit when cooled.

radiator hoses that suck in, are usually due to a bad radiator cap. detroit diesels were bad about this in 2003

I was told on here it was due to res tank cap being bad.

bad radiator cap will cause radiator hoses to stay flat when cooled

Mine was never flat on my 02.

So do I need a radiator cap or a surge tank cap?

Same thing. There is no radiator cap, only cap is on the surge tank.

surge tank cap is what i ment, it is the same on a 2003 freightliner with a detroit

Ok thanks guys

Check underneath the truck the coolant can be splashed all over the bottom of the truck. Thats what happen to mine and i had to have the water pump replaced. Best to have the pump replaced soon because it will cost you more if you have to buy DEX COOL every day or other day.