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Discussion Starter · #1 ·
Okay I mentioned in another discussion I started which I think was in the wrong category about my towing issues. I have a 2008 LMM deleted on 33s and it is tuned but I don’t like hot rodding it or anything like that. I just want my truck to be reliable. I was towing my side by side which the machine and trailer is probably around 2500lbs and I definitely can feel the weight which I wouldnt think a truck like mine would have any issue at all hauling. It does tow it fine and doesn’t really struggle it’s that my egts seem to rise fairly quick. Even when I’m not towing anything I can easily hit 1100 degrees when going up a hill so when I am towing a small, light load it goes up to 1100-1200 kinda fast. Keep in mind I am running on my “stock” tune which is a 30hp tune. Guy at my work says he had a friend who had the same issue with a clogged intercooler?? I don’t want to spend thousands in repairs I don’t need. I also have a 26ft toy hauler and it should be able to tow that like nothing as well and the egt rises and I know the max is 1350 but I also don’t want to be a road block when I’m hauling. Any ideas?
 

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Yea cleaning your cooling stack is a good start. Are you running any monitors? Curious if you're getting a boost leak. Your boots could be starting to dry out. How many miles?
 

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2017 GMC Denali 2500HD, 3.5" Rough Country Lift, 305/55R20 Cooper Rugged Trek, Paragon Bed Cover
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A few things to check:

Clean air filter. If the truck can't get enough air it will use more fuel to compensate and produce the required power. More fuel = higher EGT.

Clean the cooling stack, but I'd be surprised if this was your issue, unless you're also noticing coolant temps running hot as well.

Are you using the tow/haul mode even when pulling the lighter load of the sxs? Next time you pull, try putting the truck in tow/haul, and use manual mode to lock out 6th gear (use the +/- button to make the display show M5). Keeping your RPM up around 1800-2200 should not be getting you much further north than 1000°F EGT pulling that small load, even going up a light grade at highway speed.

Who did your tuning? I ask because not all tuners are created equal. Many tuners realize that an easy way to get more power is by dumping fuel. If you're using a tune written by someone who didn't know what they are doing, you could definitely be seeing the effects of that inexperience.
 

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Discussion Starter · #5 ·
A few things to check:

Clean air filter. If the truck can't get enough air it will use more fuel to compensate and produce the required power. More fuel = higher EGT.

Clean the cooling stack, but I'd be surprised if this was your issue, unless you're also noticing coolant temps running hot as well.

Are you using the tow/haul mode even when pulling the lighter load of the sxs? Next time you pull, try putting the truck in tow/haul, and use manual mode to lock out 6th gear (use the +/- button to make the display show M5). Keeping your RPM up around 1800-2200 should not be getting you much further north than 1000°F EGT pulling that small load, even going up a light grade at highway speed.

Who did your tuning? I ask because not all tuners are created equal. Many tuners realize that an easy way to get more power is by dumping fuel. If you're using a tune written by someone who didn't know what they are doing, you could definitely be seeing the effects of that inexperience.
I had just cleaned my air filter. The coolant level doesn’t get hot just the egt that worries me because that light of a load shouldn’t affect my truck at all… I got it tuned by a pretty well known place here in Reno but what worries me is that they’re about performance. My stock tune is a 30hp tune above what it actually really is stock. My next two towing tunes go up 25 more hp and then 50hp. My max tune is 250hp which will blow the guts out of the truck and 250 is wayyyy too much for that truck. I only use tow/haul when it starts to get close to 1100 degrees then I will click it on. I just wouldn’t think I would need tow/haul mode for such a light tow behind it. I could be wrong I’m just new to all this
 

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It doesn't hurt the transmission to use the tow/haul mode, so I always recommend using it any time a trailer is hooked to your truck.

Try locking out 6th gear next time and see what your EGT's do on that run.

I'll be honest, I think your tune is the problem. My LMM was tuned by a reputable place in Canada, and towing my 11k lb camper I wouldn't hit 1100 for very long on the heavy tow tune of +30hp.
 

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Discussion Starter · #7 ·
It doesn't hurt the transmission to use the tow/haul mode, so I always recommend using it any time a trailer is hooked to your truck.

Try locking out 6th gear next time and see what your EGT's do on that run.

I'll be honest, I think your tune is the problem. My LMM was tuned by a reputable place in Canada, and towing my 11k lb camper I wouldn't hit 1100 for very long on the heavy tow tune of +30hp.
I think I may have found the issue, I wasn’t using my tow tune which apparently they put in different shift point within the tune and I was running stock without tow/haul mode. I will give it another shot and see if that results in a better tow
 
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