ATT, hood IC or GL4 ?

[Joey D]

It was while merging on the highway, not to long maybe 1-2 minutes.
What temps have you seen towing?

 

[Slim Shady]

It was while merging on the highway, not to long maybe 1-2 minutes.
What temps have you seen towing?

When I have been at 14 15 psi boost I have seen 230 F IAT with a ambient temp of 90 f plus, never stayed at 14 15 to long.

 

[Joey D]

My intake temps settled to around 195-205 on the rest of the way home, downhill they dropped to 155 but climb back to around 200 for the most part.

 

[Slim Shady]

My intake temps settled to around 195-205 on the rest of the way home, downhill they dropped to 155 but climb back to around 200 for the most part.

Towing boost around 10 psi constant? That is about the normal at an ambient temp of 90 f. What rpm were you running? I usually am around 2200 to 2300 towing heavy.

 

[Joey D]

RPM's were around 2100-2200 in OD. Power was down as well which I suspect the ecm was defueling.
I will do the rad clean this week with the coolant flush, new stats as well, and new fan clutch.
My cooling system is all factory except for 2 flushes and 1 rad clean out a long time ago.

 

[midniteplowboyy]

Boost was 14-15lbs, ambient temp was around 85 or a bit hotter. Towing weight 10500lbs, cat on a GN trailer.

Not calling you a liar, but that seems kinda light for a cat(unless feline) and a GN trailer. Figured it would weigh more unless its a tiny dozer and a light trailer.

 

[Joey D]

Not calling you a liar, but that seems kinda light for a cat(unless feline) and a GN trailer. Figured it would weigh more unless its a tiny dozer and a light trailer.

You callin me a liar):h
Big cat skid steer on my GN trailer.
Skid stter weighs just under 8000lbs
trailer weighs under 3000lbs, could be just under
Total weight under 11,000lbs so I may have been a little off but not much

 

[Turbine Doc]

Tim, What IAT do you see with no intercooler? I did my 1st hot temp tow today and truck is running hot, IAT were over 260 degrees and coolant temps were over 210. I have an issue with my fan, clutch didn't engage at all today while towing. I am going to do a rad clean and cooler cleanse and add wetter water but the intake temps aren't helping.

I have A WMI kit waiting to go in mine, for the transients that may happen into the 200+ IAT area, I ran the burb Ms to Ga a few weeks ago 111 mph, 95F day boosting into 13 psi territory, with 257 IAT, 3200 rpm, 100% engine load, 198F coolant (50/50 Dex & water). I need to post that data, just like with the GM turbo IATs do not really start getting elevated until you start getting above 11psi, it's not the turbo per-sei, it's the physics of compressed air. FWIW I pushed it to see when de-fuel occurred, and it happend pretty fast about 279F is what I captured on scanner, I don't know the data refresh rate to know the actual setpoing for defuel, no code was set it just went limp and set a 50mm max fuel rate, cleared with a shutdown/restart.

For those that don't have the ATT yet, where the different turbo nuiances come into play are when/what rpm you hit that peak pressure, when I was running the GM-8 to run 100 mph I was always in 10+ PSI boosting, now depending on the ambient conditions I may be be in 10+, I've run 100mph with only 8 psi boost on a cool day with ATT @130 IAT.

There is some data (not mine, but someone who is very intimate with the innards of the 6.5 shared that with me) that says 150F IAT is the ideal temp for the charge air for the 6.5, 99% of the time I'm seeing that or less and boost levels pressure wise to attain speed/power about 1/2 the boost than was required with the GM-8, non towing.

Biggest load thus far with mine towed since going ATT & no IC has been 3K in a 6Wx12Lx7H' enclosed trailer on 80F day @75mph, no overheating issues or high IATs with that load, IIRD 157 IAT with 8psi boost on hills; but towing big there may be need for WMI.

If you haven't done a deep clean of the rad, or it's been a while Id be looking there, especially if you aren't running sustained IAT in the 260F region, I don't the occasional excursion there is going to hurt you much, I'd also look into aux trans cooling if you are going to tow big often as that helps as well.

 

[Acesneights1]

Joey, I don't remember, but does your truck have a bodylift as well as suspension ? Plus don't forget Joey's truck is turnin some big tires. That adds alot of strain(I love that straight axle conversion).

 

[davo727]

Hey Tim, You have a get out of jail free card or what? You go 111 mph everywhere

 

[Joey D]

Joey, I don't remember, but does your truck have a bodylift as well as suspension ? Plus don't forget Joey's truck is turnin some big tires. That adds alot of strain(I love that straight axle conversion).

No body lift and it has 35in tires.

 

[Joey D]

Tim, I am working on the coolant temps now, flush the coolant and clean the radiator and coolers. The fan never came on like I said in another post so I will replace the clutch as well.
I don't want to set up a WM setup and may look into a intercooler. I know you removed yours but was it hurting power or did you find it's not needed most of the time?

 

[Acesneights1]

If the rad was very dirty the clutch will not sense the temp properly. Joey you could look into the hayden severe duty clutch. They have the part#s on thier website and can be ordered though any NAPA dealer. About 140$ IIRC.

 

[Acesneights1]

Do you have 4 bolt or centerhub ? I have the old one off my 2000. I don't think there was anything wrong with it. you can have it. It's a centerhub.

 

[midniteplowboyy]

You callin me a liar):h
Big cat skid steer on my GN trailer.
Skid stter weighs just under 8000lbs
trailer weighs under 3000lbs, could be just under
Total weight under 11,000lbs so I may have been a little off but not much

Sorry, my bad.

I just saw cat and assumed dozer.

 

[Veg_Out]

RPM's were around 2100-2200 in OD. Power was down as well which I suspect the ecm was defueling.
I will do the rad clean this week with the coolant flush, new stats as well, and new fan clutch.
My cooling system is all factory except for 2 flushes and 1 rad clean out a long time ago.

Joey,

You may already know, but be sure to get the actual AC Delco T-Stats. They are stupid expensive, but actually work.

Call me the voice of experience on this!

 

[Joey D]

I will do GM stats and a new sensor in the head as well.
Ace, I have the 4 bolt fan hub. Thanks for the offer though.

 

[Matt Bachand]

I will do GM stats and a new sensor in the head as well.
Ace, I have the 4 bolt fan hub. Thanks for the offer though.

Bend the tab out 1/8th inch or so as the DIY Fan clutch mod thread indicates. See if it helps before buying new.

 

[Joey D]

Bend the tab out 1/8th inch or so as the DIY Fan clutch mod thread indicates. See if it helps before buying new.

I will try that. I am hoping that the rad is clogged enough to limit the air flow through the stack causing the fan not to come on.
I am going to do a new radiator as mine is origonal equipment.

 

[Turbine Doc]

Hey Tim, You have a get out of jail free card or what? You go 111 mph everywhere

No I got tagged in June, 78 in 65 in Va, I did not know entire state of Va was 65 mph on interstate, had passed thru some construction thought that was why the low speed, got lucky as I had just come off of 85 mph about a mile earlier.

111 is my "warp speed" setting for the burb for now, when I grab data sets, I take at 5 mph increments until I hit max speed 100% engine load on the burb it's 111, last time I maxed the truck out it was 119 mph, but that was before FTB-ATT and a few other mods, I haven't really had a "safe place" with traffic to "open up" the truck fully to know what it will do now.