Pulled the lower radiator hose and dumped the coolant today. It hasn't been changed since the truck was new (98,500 miles). I also dumped the overflow tank. Refilled with about 2.25 gal of fresh Prestone 50/50 and a bottle of DCA4, and dumped another gallon into the overflow tank.

Went for a drive. Headed up a hill with a nice twisty road near home... slow, twisty. I've driven it many times without issue. This time when I reached the top, I was at 262 deg according to my Ultragauge. Ugh. Fortunately it was downhill most of the rest of the way home and it cooled back off. It did get back up to about 242 just before pulling into the driveway, but I let it idle for a while and it got down to 210 or so before I shut it off.

What do you think? Stuck thermostat? Do these things need to be burped?

Rob

 

You have an air pocket.....pull the heater hose coming out of the head to purge it.

Sent from my XT1080 using IB AutoGroup

 

Thanks! Okay silly questions... where exactly is that hose, and once I do that, then what? Run the motor?

Rob

 

Rob,

This is the best thread you will find on the subject:

https://www.dieseltruckresource.com/...=coolant+flush

 

It does sound like an air pocket to me too.

A little late but the coolant you used is not the correct one. These engines require a HOAT coolant like the Zerex G-05

 

Thanks guys, got it all worked out.

And no it doesn't require HOAT. Did a lot of searching on that topic.

Rob

 

Better read your owners manual. Says to put the HOAT type in. Using propylene glycol is not recommended as the vehicle isn't designed to use it.




47

 

BTW, no need for DCA4. That is a requirement for wet sleeved bores. Our engines are 'parent bore'.

 

Wrong!! But it's your engine. Damage it if you want.

This ^^^

 

Very true, this is the best write up on changing coolant....yes you have an air pocket, read the instructions below. I put my coolant in until it ran out of this hose and there were no problems. Engine should be off.

https://www.dieseltruckresource.com/...=coolant+flush

I agree with post on HOAT coolant for these engines! My research convinced me it was the only one to use. NAPA is the only place I could find it. I'm sure there are other places.

 

RobG, just like ^^^^ all the above typed, get some Zerex G-05.

 

or he could pull one of the pipe plugs on the head that requires a 3/8 drive ratchet to bleed the air out fill it till coolant comes out.
and deffentifly HOAT