Help: Hot transmission tunnel

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Driving at 70 MPH today with an outside temperature of ~95 deg F, I measured 140 deg F under the carpet of the transmission tunnel on the passenger side. On top of the carpet is 100+ deg, which makes it uncomfortable to sit in the passenger seat. This seems crazy to me--there should be a ton of air flow at 70 MPH. I measued exhaust back pressure in one of the O2 sensor holes and it was basically zero, so I don't think the cats are plugged. Any insights?
 
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Road Apple

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Just installed multiple layers over the interior of the truck. I started with a layer of Aluminum heat shielding over the transmission tunnel area, bought off of Amazon. I added a layer of Kilmat 50 mil and a layer of Noice Red 150 mil over the enter cabin.

We’ve been driving this week through Arizona and Utah with temps in the 90’s. The transmission tunnel is fairly cool on the sides near driver and passenger legs, but pretty warm over the center console/shifter area, where is difficult to apply shielding.

Big improvement overall. The family is comfortable and so is the dog on the floor.

4752762E-37E3-48D5-9765-A47920303252.jpeg
 
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I've had the same problem. Check under the console around the transfer case shifter. I had a small gap under the plate surrounding the transfer case shifter, and after tightening it down then problem seems to be resolved. I would check there.
 

Bambusiero

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isn't most of that air-flow around the engine and through the transmission tunnel - heated radiator exhaust? So - that air is typically heated to 186 F (or so) under normal operation, right? It's just normal - nothing is wrong. All you can do is insulate the tunnel better inside.
 
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I removed my rear heater and there is a hole in the floor where the coolant tubes come into the cab. A rubber padding surrounds the tube and from its condition was completely deteriorated and brittle. Location was located right on top of the exhaust bend. Slightest holes in that padding will cause very hot conditions in that area as well.
 
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Just installed multiple layers over the interior of the truck. I started with a layer of Aluminum heat shielding over the transmission tunnel area, bought off of Amazon. I added a layer of Kilmat 50 mil and a layer of Noice Red 150 mil over the enter cabin.

We’ve been driving this week through Arizona and Utah with temps in the 90’s. The transmission tunnel is fairly cool on the sides near driver and passenger legs, but pretty warm over the center console/shifter area, where is difficult to apply shielding.

Big improvement overall. The family is comfortable and so is the dog on the floor.

View attachment 2745305

Gonna do this soon myself too. Can you list the amount of insulation you bought? Thanks
 

Road Apple

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Gonna do this soon myself too. Can you list the amount of insulation you bought? Thanks

The heat shielding from Amazon was minimal. I’d would double this and extend it further away from the transmission tunnel if I did it again.

Brand: CaliBikerClub

Aluminum Heat Shield Protection with Fiberglass and Self-Adhesive Backing Heat Barrier (1 Sq Foot)​


2 boxes of the Noice RED 150mm 36 sq ft was enough to finish the main cabin, but wouldn’t finish the doors.

Same for 2 boxes of the Kilmat 50 mil 50 sq ft. I needed a bit more to finish the doors.

I used every scrap to cut and paste into the nooks and crannies, especially around the shifter. That’s where a lot of heat and noise escapes into the cabin. The doors are worth the effort. The quarter panels take some time and patience to cover.
 
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years ago I added a layer of mass loaded vinyl that had a radiant on one side to the passenger side footwell and the transmission tunnel and it made quite a big difference. Some better insulation other than a radiant barrier should make more of a difference.
 

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