Making an old truck feel new

[GMC Guy]

Well, my factory box just started to leak... so I’m now looking more seriously at the CPP 500 series box. still kicking myself for not replacing it when i had the entire front end off the truck...

[GMC Guy]

Originally Posted by Gregski

I am fixated on that engine bay, I think I've been staring at it for hours, that is poetry under the hood! Incredible job mate! Wow!

Thank you sir! I appreciate that!

[GMC Guy]

can’t wait for the outside to look decent lol

[Gregski]

I would coat the floor and behind the seat area with SEM RUBBERIZED UNDERCOATING Part #39523

You may also shoot it inside the doors once you gut them, this prevents the truck from sounding like a tin can

new cab mounts also help reduce the squeeking, and brand new quality door and window weatherstripping reduces whistling noises

https://www.semproducts.com/product/...rcoating/39523

[Gregski]

Originally Posted by TKCR

I go crazy over noises and everything I have done, has helped a ton. I have heard that some people are getting wind noise after having their vents rebuilt. Mine are way better now. Also replaced all the other seals and door sweeps. Like Mattchu60, I got the upper door seal too, I just never installed them since the wind noise is better.
The other things I did, was while the cab was gutted to change interior color, I added Fat Mat to the floor and roof ( under the headliner). Fat Mat on the back wall behind the seat. Then the cardboard piece behind the seat, I put speaker carpet on it. Also lined the insides of the doors with Fat Mat.
On the cab floor: on top of the Fat Mat, I put the factory tar mat back down. I then used a foiled back jute padding. Then the new carpet, which had jute on the backside.
Behind the rear speakers, there is a space up between the rear panels. I put insulation in there.

damn that's tight!

[GMC Guy]

Originally Posted by Gregski

I would coat the floor and behind the seat area with SEM RUBBERIZED UNDERCOATING Part #39523

You may also shoot it inside the doors once you gut them, this prevents the truck from sounding like a tin can

new cab mounts also help reduce the squeeking, and brand new quality door and window weatherstripping reduces whistling noises

https://www.semproducts.com/product/...rcoating/39523

I used the Rustoleum undercoating inside and underneath way back when, and then fat mat over it. I’m also very pleased with the Precision weather stripping I’ve recieved and can say my windows roll up and down like butta.
I believe that the dash/firewall area needs the most attention as far as added insulation and I’m looking forward to tearing it apart and adding lots of the closed cell foam.
All newer vehicles have some kind of insulation on the engine side of the firewall, kind of curious if it’s possible to do something there that doesn’t look terrible.

[D13]

Look at what was done on the diesel trucks for inspiration. Unless yu never see rain, snow or mud, external insulators are counter0indicated.. although a modified hood insualtor might be useful. But there are a lot of things to go around on the outside of the firewall.

[tucsonjwt]

Whatever you spray the floor with, make sure that you insulate over it. I had my 76 sprayed with Rhino Liner all the way up the back wall and did not cover it with anything. The transmission hump was super hot.

[bennylava]

Originally Posted by tucsonjwt

Whatever you spray the floor with, make sure that you insulate over it. I had my 76 sprayed with Rhino Liner all the way up the back wall and did not cover it with anything. The transmission hump was super hot.

They have sprays which are designed for the undersides of vehicles. I don't think rino liner is one of them. There is even one designed for heat... can't remember... lizard skin?

[Keith Seymore]

Originally Posted by 1980c10

I've battled the vent noise many times. I've rebuilt them myself twice. I eventually swapped them with the newer style from a late '80s suburban and new precision seals in those as well. It was a big improvement. Dynomat inside the door on the outer door skin was a really nice improvement. As far as the steering; the adjusting screw on the steering box is critical. Too loose and the steering feels loose. Too tight and the wheel won't return to center. Trial and error worked for me getting this set. I'm sure their is a more proper procedure for this...

The proper procedure is shown in the Unit Repair Manual.

It is supposed to be done on a bench; there are two adjustments. "Preload" is done with the big nut surrounding the splined input shaft and has a defined rotational torque of the shaft (something like 10-12 in lbs). The "overcenter" torque is the jam nut and screw that you guys are messing with, and the rotational torque of the input shaft for that setting is 20 in lbs, I believe.

K

[homemade87]

20 In lbs , Thats interesting Keith . I never new that value . When ever I tried to adjust I never seemed to get satisfaction . Some better but never what it should have been . I found out after screwing around with many over the years it time for a rebuild or replace . After that all was well for many years .