hi guys, Im trying to trouble shoot for a friend. He has an 07 5.9 megacab with 6 inch lift, 37inch rubber, banks air intake, intercooler, ram intake, bullydog pmt, stock turbo. under normal driving conditions whether he is on stock mode or performance usually the bullydog pmt will say defueling engine temp to hot. It will run 228 degrees without hauling. The other day he hauled a load of straw and it got alot hotter than that. hes only had the banks and bullydog on for maybe 1000-2000 miles this summer. Could his fans not be working? I KNow my 03 and my edge are different and my trucks not lifted but my engine temp struggles to get above 205! EVER! Any opinions or ideas would greatly be appreciated. TIA Jordan

 

The cooling system is pretty simple; not much too it. But there are lots of reasons for an engine to run hot. Anything from a clogged radiator to low coolant.

The first thing I would do is return the computer completly back to stock. If the problem resolves, it's the tune. If it doesn't, then you have to start looking at the mechanical aspects of the cooling system.

 

+1 on that, and also could be a faulty coolant temp sensor. Check the temp with a thermal gun.

 

Is he running a bulldog PMT with a Banks programmer??? Something dosen't sound right at all.

 

I can't see how a programmer would cause your engine to run hot unless you are constantly driving like a maniac. If it gets that hot while driving normally then it's not any programmer or fueling box. I have never had any issue like that.
I'd check to make sure the fan is working. If it's not on when the truck is running 228 degrees then it needs attention. It could possibly be the fan clutch. If the fan is working properly then I'd check the thermostat and, of course, coolant...

 

Thanks for the replys guys. Me and my friends brother who installed everything talked about it today and we are going to check the fan and thermostat next. We both are pretty stumped on this bcuz between 6 commonrails and 5 12valves in their herd they have never had this problem. Some of them are even modded much more than his megacab. My friend runs it hard but not hard enough to do this. We had it hit 220 cruising at 70mph on the highway on level ground.

Hes not running a banks box. Hes just running the bullydog.

Thanks again guys.

 

When I Installed my cam/valvetrain, I noticed the fan is electronically controlled. it has a connector on the front of it that runs up underneath and back to the wiring harness with a big jamnut on the pulley. So best I can figure instead of the viscous clutch warming up, it clicks on when the engine temp gets to a certain range. So I think it would probably throw a CEL if it was malfunctioning. Is it possible you have air in the system or a clogged radiator? When you replace the thermostat and let it warm up, if the top hose and the bottom hose are different temps/pressures, theres your answer. I don't know what the symptoms of head gasket failure on a diesel are, but I wouldn't rule that out either.

 

He's definitely got a cooling system problem if it gets that hot cruising at 70 mph. I doubt it's even the fan then. I'd lean towards the T-Stat..

 

Thanks for the info guys. I hope its a simple fix . Its not my truck but i still hate knowing that its not running rite. Jordan

 

also chek for lots of dirt and crap between the rad and intercooler,mine was full of crap and it ran cooler after i ran the hose between them,

 

Turns out there was a lose sensor

 

water pump...happened to me same circumstances...finally blew and covered under power-train warranty

 

Glad you found the problem and that it was something simple!

Just curious does the PMT use the stock temp sensor for its info? What was the temp gauge in the dash doing?