1972 GMC K5 then and now

[72gmck5]

The transmission heat wasn't an issue, the exhaust however was cooking my feet before I added the heat insulation.

That's basically what I'm after. The exhaust heats the floor and starts to bake us in the truck. I have carpet but its still really warm. On the trail its pretty bad cuz we aren't really moving fast enough for the air to help dissipate it. I'll look into the summit and Dei stuff. I'm pulling the front carpet and interior pieces tonight and will see how much of everything I need.

 

[6872xtc]

I believe that the exhaust heat runs right back into the transmission tunnel. The transmission is only 200* or so. The exhaust can be 400* to 500*, I am not positive. I have seen my temp gun goes out of range at 500* , but I have seen it happen on exhaust. The air from the engine fan blowing across the exhaust, heats the floor quite well. I have the tunnel insulation going to the bottom of the pinch weld flange where it meets the firewall and back from there.

@mrk5 said that he installed his with the engine and transmission in.... he has more patience than me, I thought that it was something of a small challenge with the body on jackstands..

 

[72gmck5]

Got the front interior out and started measuring for seat mounts and area for sound deadener. 30sqft should cover the entire area.

 

[AgDieseler]

There’s a three layer foam dynamat makes that goes over the foil stuff. It made a huge difference in how heat and sound transferred in my truck.

David

 

[ekajkrats]

In the front cab area of my blazer, I used Al's Heat and Noise reducer and some peal and seal and then the formed rubber mat kit and noticed a huge difference from the bare floor. Of course, if I had used cardboard I would have noticed a difference seeing that I'm in flip flops driving 95% of the time.

Honestly, I was trying to do it as inexpensively as possible and thought the rubber mat would look mostly decent and not rot away from the elements. The Al's HNR also seemed like a first good layer. And it's worked out well for me.

 

[72gmck5]

Been a busy weekend and trying get out to work on this as much as possible.
I did order up a noise and heat insulation solution that from what I’ve read should produce favorable results. Kilmat plus a layer of noico heat and sound barrier on top of it.

I also made the beginnings of my seat brackets and getting them test fitted. I do need to trim the outside slider on each seat as it’s longer and hitting the stepup in the floor and not allowing the seat to go back as far as I’d like.

 

[mrk5]

I put the DEI transmission tunnel shield on the underside of the '90 after @mrk5 said that he liked what it did for his. Then the summit stuff on top of the footwell areas, then the carpet pad stuff.

The DEI stuff was pricey, but if it works, I'm fine with it.

@mrk5 said that he installed his with the engine and transmission in.... he has more patience than me, I thought that it was something of a small challenge with the body on jackstands..

I can verify, I did say these things.

I don't know the source of the heat but in both the K5 and the crew cab, the floor on where the trans tunnel meets the floor pan would get so hot my wife in her sandals would have to move her far away. The heat shield under the floor eliminated this problem.

 

[72gmck5]

I can verify, I did say these things.

I don't know the source of the heat but in both the K5 and the crew cab, the floor on where the trans tunnel meets the floor pan would get so hot my wife in her sandals would have to move her far away. The heat shield under the floor eliminated this problem.

On the one you used was it self adhesive or did you have to use fasteners?

 

[mrk5]

On the one you used was it self adhesive or did you have to use fasteners?

It was adhesive backed. The product claimed to have very aggressive adhesive. It seems to have held on pretty good. I notice a few places near the edges lifting, but the bulk of it is still stuck. I think it's been 3 or more years now. I my truck didn't have a bunch of gnarly stuff under the trans tunnel. I just wiped it down with lacquer thinner and isopropyl alcohol as best I could before application.

 

[72gmck5]

Burning the midnight oil and got the seat mounts built. Pretty happy with how they turned out and the added functionality I get with them.

 

[mrk5]

Looks nice!

 

[ashman]

Right on! Can't wait to see how you like them down in Moab.

 

[72gmck5]

Looks nice!

Thanks!

Right on! Can't wait to see how you like them down in Moab.

I need to drive it tonight and see if my butt like them. Plus need a baseline for noise and heat before the insulation goes in.

 

[ashman]

If you need a destination, come on by.

 

[72gmck5]

Another late night after running errands and being with the fam I got out and made some progress.
Turned on the truck and let it idle for 10-15 minutes to see how hot the floors got. Started at an ambient 85* and got up to about 120*. While wheeling or just driving it would for sure be hotter.

So I pulled the seats back out, wiped the floors down and started on the first layer being Kilmat. For now I’m just doing the interior but I do think I’ll be adding a heat shield underneath later.

 

[72gmck5]

Made some more progress today. Since I have a 700r4 and NP205 I had modified my trans tunnel for the shifter being further back. This left a larger that stock hole that my shift boot barely covered. I made a patch and covered part of the hole plus filled in various screw holes. This will let me move the shifter boot lower and properly cover the opening.


Finished up with the layer of sound deadener and got a bout halfway through the second later of foam.

 

[72gmck5]

Woohoo pretty much back together!

 

[72gmck5]

Went out on a short drive today and the seats are comfy, much more supportive than the old ones. The cab seems a fair amount less echoy. I’ll have to check on the floor heat but I’m sure it’s better.
I’ll try check with my laser gun tomorrow.

I also added some cargo rails to keep stuff tied down in the back.

 

[ashman]

good call on the rails. I REALLY need to do the same.

 

[AgDieseler]

Nice details. I think stuff like this really enhances the enjoyment of a long day on the trail.

David