could the radiatior hose be collapseing under heavy load and resricting the flow?

 

Because you are hauling heavy loads the blowby exiting the crankcase is increased.This oily substance is somehow pushed into the radiator dirt and debris stick to this oily mess restricting the air flow thru the radiator.The best way to inspect the radiator is look behind the fan with a flashlight.The whole diameter of the fan you will see is plugged by this oily tar.I have found the only way to clean this mess out completly is to remove the radiator,lay it on the ground soak it with engine gunk,and blow it out from the inside out with pressurised water.It un believable how much crud will blow out of there.Don't try to do it in the truck.When you are done get rid of the blow by bottle and extend the hose passed the steering gear box.Merv

 

fitzer sorry to hear of your problem too,when you climb a hill empty it stays around 180-195 then when you put a car trailer behind it it goes to 220 and starts to shut the engine down right?is that what yours is doing?do you hear the clutch fan?my fan was bad and now i can definetly hear it,but it didnt solve my problem yet im going to put a new radiator in it this week and see what that does, if that isnt it then i think im going to pull the head off it and replace the head gasket,it doesnt seem like that is what it is to me but im running out of ideas to fix it,but i will post when i get it fixed how many miles are on your truck?

 

pecandude, i was thinking the same thing last week about the hose,my friend has a chassis dyno im going to run it on there and see if it sucks it shut and on there i can use my heat gun and see what is going on better,good suggestion though

 

reread the post from Huff nPuff. I have a 2001 and jerked around trying to fix it for a couple months. Huff nPuffs diagnosis was my cure.
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herb was it getting to the temps like i mentioned and starting to shut it down?did you replace it or clean it,and how many miles were on it when you had the problem

 

While your truck isn't that old there are alot of rounds on it. I think you'll find the radiator will take care of your probs. With the size of the cooling systems on these trucks the auto trans will NOT push the engine temp up that high.

 

im ripping the rad out tomorrow,ill know this wek when i hook the trailer to it, i appreciate all your help and advice,what would we do with out a awesome site like this for such knowledge

 

I had a gasser doing the same thing. There was 2 problems i found that fixed it. The bottom radiator hose was sucking shut under high rpm's. and i was running nearly straight antifreeze. It was supposed to be 50/50 mix. Hope this helps.

 

switched antifreeze this week and made sure it was 50-50 mix and im going to check the hose this week,fingers are crossed

 

hey fitzer & other members, well mt truck is fixed now and like i said im going to tell you what to do,first make sure you here the fan clutch kicking in second ,thermostat made my truck drop 10 degrees not under load(buy one from dodge, third which definitely fixed mine,take the radiator out of the truck,as soon as you unbolt the shroud from the radiator look at it while its in and you will be discusted,i preasure washed my radiator 3 times and it looked clean where the fan blows,but when i took the rad out ,it was still clogged up with the black tary stuff from one end to the other,so i super cleaned the radiator like 10 times preasure washed it 10 times in both directions,did the same with the trans cooler and a/c condensor and the intercooler,i also eliminated the catch can on the front of the engine and ran a hose all the way to the back and dumped it behind the rear,no no more oil crap off of that under my hood,hope this helps you guys and thanks to all that posted to the subject i and alot of other members appreciate your time and info

 

I ran my crankcase breather hose like that to the rear until the 1st winter when the hose froze up and plugged the vent process.
Couldn't see ANY blowby coming out!

Now I've got it dropping down the front of the block and ending just below the front axle tube. Can see blowby now even on the coldest days. And it doesn't blow any oil on the chassis bottom, either.

 

Instead of heater hose for the extention, go to a hardware store and get the soft plastic transparent hose in the same size, looks a little better and is cheap. Let it hang to the ground and cut it off even.

My commercial engine came with that hose for the breather from Cummins.