What heat insulation for transmission tunnel?

SouthernTJ2000

SouthernTJ2000

TJ Enthusiast
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Mar 19, 2024
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200
Location
Tomball, TX
I picked up a ’00 5 speed back in February. Now that the heat of summer is on us, I’m in the Houston area so heat and humidity are doing their thing. I’ve noticed I get some excess heat coming from the right side of the transmission tunnel near the parking brake area. After some research I see the majority of its probably from the exhaust/cat, as it sits right there. It does have carpet, however its nothing fancy or “thick.” I’d like to lay some heat insulator on the tunnel and associated areas. I am not concerned with noise at all. I want to block as much heat as possible. With that, I’ve been doing some research, however not sure what to go with. Most of the stuff I’ve found seems to be more for sound deadening and a “heat insulator” second. I don’t care to do the entire pan and would prefer something I can cut to shape. What are some of y’all using to knock the heat down a tad? Thanks.
 
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DEI Boom Mat...they also make a transmission tunnel head shield. I put some under my original TJ tub. On round 2 I wrapped the exhaust from the header to the cat in exhaust wrap. Found that to be far more effective.

IMG20240605174041.jpg


-Mac
 
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Seems like boom mat is marketed as sound deadener as opposed to heat shield. I need to solve this problem ahead of replacing the carpet in mine.
 
In a month or so I am going to use Noico front to back and then new carpet. The factory placement of the 3rd cat on my 06 LJ is dumb. Way too close to the tranny. I found a small Magnaflow cat that I will place as close to the muffler as possible. This will get that heat further back. Also if you go under your Jeep you will see the factory aluminum heat shields. I am going to grab some of that stuff and cut it to make additional heat shielding.
 
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hear said:
There are 2 classes of bedrug, right? Regular and then one with the mass backing or whatever? Which did you use?

And how much of that CSI stuff did it take?
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Bedrug doesn't offer mass backing. The company makes Bedtread which is a rubberized floor covering. I have it in the back of my Jeep but it doesn't offer any more insulation than the Bedrug. ACC offers a carpet with mass backing that has good reviews. It weighs significantly more, if that is any concern. I went with the Bedrug specifically to try and save weight. If that wasn't a concern I'd probably go with the ACC. The Bedrug is nice but moves around unless held in with velcro. I also have it in the back of my truck and it's claims of stain and fade resistance are not accurate. I think for interior carpet it is good and I have been happy with it. It is very light and easy to remove and clean.

When installed the CSI in the front I used most of the 4 x 6 roll as there was some waste when cutting it.
 
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LONGJP2 said:
Just this stick to the floor or lie loose?
I've always worried about water getting under the products that are stuck/taped down and causing rust.
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I just layed it down loose. I did spend a good amount of time fitting it so it doesn't move around. If needed I can remove it relatively easily as it is just held together by foil tape. My Jeep hasn't seen rain or water since before 2017 so it wasn't a huge concern for me. I do imagine it would absorb water if it got wet so it might not be a great choice for Jeeps that are frequently open to the elements. It does have a foil backing which should help keep the floorboards dry should it get wet.
 
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SouthernTJ2000 said:
I picked up a ’00 5 speed back in February. Now that the heat of summer is on us, I’m in the Houston area so heat and humidity are doing their thing. I’ve noticed I get some excess heat coming from the right side of the transmission tunnel near the parking brake area. After some research I see the majority of its probably from the exhaust/cat, as it sits right there. It does have carpet, however its nothing fancy or “thick.” I’d like to lay some heat insulator on the tunnel and associated areas. I am not concerned with noise at all. I want to block as much heat as possible. With that, I’ve been doing some research, however not sure what to go with. Most of the stuff I’ve found seems to be more for sound deadening and a “heat insulator” second. I don’t care to do the entire pan and would prefer something I can cut to shape. What are some of y’all using to knock the heat down a tad? Thanks.
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Do you have a center console? Does it feel like hot air is blowing out of the brake lever slot like you have a turbo charged heater vent in there? If that’s what is going on I would check the inner shift boot, they wear out and disintegrate and let in hot air like you wouldn’t believe, before I replaced mine I couldn’t use my cup holder for anything that I didn’t want to be the temperature of a fresh cup of coffee.

I don’t think excessive heat from the exhaust radiating through the floor with factory carpets is really an issue unless something is wrong with your cat.
 
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jwilkinson01 said:
Do you have a center console? Does it feel like hot air is blowing out of the brake lever slot like you have a turbo charged heater vent in there? If that’s what is going on I would check the inner shift boot, they wear out and disintegrate and let in hot air like you wouldn’t believe, before I replaced mine I couldn’t use my cup holder for anything that I didn’t want to be the temperature of a fresh cup of coffee.

I don’t think excessive heat from the exhaust radiating through the floor with factory carpets is really an issue unless something is wrong with your cat.
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That's exactly what is going on! Ill pull the console and check the inner boot. I noticed its not to bad at "around town speeds", say under 55 or so. But once I get past 60 or so, its like a heat blower is coming through the emergency brake slot.
 
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