Is this a known issue? Is there any solves or thoughts? I just got back from a 5 hour one way camping trip. If I didn’t have the air on it was like I have the heat blowing on the floor. It got a little warm. I had noticed this in the past a bit but didn’t think of it. My wife however has had some health changes and this heat can get her not feeling well quickly. Just curious as to if this is the way of the beast? Anything I can do to help?

I was towing approx 6,000 pounds, 72-75 mph, EGTs were a consistent 900-1000 degrees.

 

@Wesley Green took some heat and noise reduction steps a few months back, but I think his was preventive maintenance and a target of opportunity while the transmission was out.

I don't think you have a ZF6, but if you do the white and black shift lever boot can let a lot of heat in if it is damaged. I replaced my torn an worn boots this past winter and it made a big difference on in cab noise and heat.

Other than that the trucks can run a bit hot in the summer. You could remove the carpet and line the bottom of the cab with heat reflective mating. The same can be done under the cab and engine side of firewall, but there is already some of that there and from the inside would be easier.

Check the grommets and pass through ports along the firewall and under the cab. Make sure they are still there and intact.

 

Correct Sous, i did. That mod holds a special place in my heart.
My thread

Post 27 shows the start of that work. Although i never really had much discomfort towing heavy maintaining 1150-1200* EGTs for hours at a time, My feet n calves area would get about 8* hotter than the air around the rest of my body when the temps were 104* outside with max ac blasting, not unbearable to me, but I'm the type that can handle heat better than cold. After all the insulating currently done and wraping the uppipes and all the exhaust under the cab the heat is maybe 2-3* more down there instead of what it was, but we didn't get to tow cross country thru the desert this year to test it out as much as normal, plus i ran out of time and motivation to do the firewall and floor from inside the cab. Oh, and i removed a 1" grommet in the firewall from the aftermarket alarm and have still forgot to put it back in.

Granted i have a Lariat which supposedly came with some more insulation than the lower teir trim package trucks have. In theory it can't hurt to add any, some is better than none, but i wouldn't pull the transmission just to add this on the heat side of the equation. For sound, it made a noticeable difference in decreased road noise tho. Even more so once i did all 4 doors.

 

Paul installed a ball valve on the heater exchange feed when he owned my truck (pre-Frankenstinky). I never shut it off to test it, but it makes me wonder if that would be part of the problem.

 

I used the heat shielding that originally was on the turbo outlet to inter-cooler pipe to insulate the firewall side of the downpipe. I went to Harbor Freight and picked up a pack of stainless steel zip ties and used them to mount the insulation. My wife says the passenger side is much cooler now. I have about 50K miles driven since the modification and everything is holding up well.

 

It’s pretty normal. I took out all the rubber floor matting and insulation and the transmission tunnel and floorboards get downright hot to the touch.