LLY Got hot

[Max Attitude]

Couple weeks ago I was towing my 96 Z-71 ext cab on a trailer home from the dunes. It was hot out, 88* according to my truck. Cruise set at 75mph, I turned on the AC about half way home (1.5 hour trip). A little later the fan kicked on and my coolant temp got up to around 230*. I turned the air off and it went back down to normal 210*. About 5k miles ago I replaced the water pump with an AC Delco because of a seal leak. I don't tow often when hot but never had an issue before. I have a full LBZ intake/mouthpiece with down pipe and straight piped exhaust. I was running on my EFI tow tune. I may have to clean the cooling stack I guess? I know the LLY doesn't have the best rep for cooling but I'm not running through any mountains here.

 

[RickDLance]

I would definitely clean the stack. Be sure to disassemble it and clean from the back side to the front.

 

[Max Attitude]

Ok, Thanks Rick.

 

[ALLY Fox]

The dash gauge is notoriously inaccurate if that's what you were going by. Mine says 210 when actual ECT is 186*. Plus, towing at 75 is a strain on the LLY cooling system when OAT is approaching 90*, especially if you're running big tires.

 

[Max Attitude]

Yeah running 33's so not real big but they are fairly heavy compared to stock.

 

[malibu795]

While its cooling stack it out replace fan clutch with hayden 2886 will help drastically on the LLYs

 

[carl.swoyer]

Might check out the clutch fan. Mine was slipping just enough to get hot more frequently . Put a new one in No more running hot. Plus have your tow mode on

Sent from my XT1254 using Tapatalk

 

[Max Attitude]

While its cooling stack it out replace fan clutch with hayden 2886 will help drastically on the LLYs

Whats different about them? I don't even want to hear the fan come on at all.

 

[malibu795]

Whats different about them? I don't even want to hear the fan come on at all.

The Hayden starts partially engage the fan around 190 and is fully on by 200° vs OEM on/off nature around 230.
Its sensitive enough that turning the AC on will partially engage the fan at idle with exception to trucks like james most of us that have done the swap rarely see any coolant temp above 210°

 

[Max Attitude]

Thanks for the info Adam. If cleaning the stack doesn't solve it that may be my next step.

 

[malibu795]

Jared
Fwiw fan clutches do wear out. Recent google says they are running ~$90.00 now
Thread about clutches....
http://www.duramaxdiesels.com/forum/showthread.php?t=65765

 

[bmc1025]

While you have the stack removed its only a 10 minute swap. Its well worth it while it is apart.

 

[Max Attitude]

Ricks suggestion should help. Made a video of it. If not familiar with the audio you probably won't find the humor in it. Sorry its vertical too.
[YOUTUBE]AXUUqnfEYOc[/YOUTUBE]

 

[PureHybrid]

:rofl:

Looks dirty

 

[malibu795]

Lol:rofl: