Dave
Thank you for the input on soundproofing my 66'. Not sure what you meant by "the rubber in the door jambs". In the restoration process all new door weatherstrips and window channels were installed. I particularly liked the "no glue" door weatherstrips. At highway speed I do not detect any cold air coming in except a little through the kick panel vents because they don't seal up 100%. When I installed the Dynamat soundproofing on the kick panels, I didn't what to cover up the vents as I don't have air-conditioning. So I guess I'll just have to live with that.
I think I agree with George (Wrenchbender Ret.), most of the noise at highway speed is just wind noise. It's just the way they were made!!!
Rubber in the door jambs was referring to the weatherstrips you replaced. Sounds like you got the doors adjusted well if you have no cold air coming in. Those vents will never seal up completely, it's the way they were designed. Sounds like you have done about as much as you can. These trucks were never meant to be luxury car quiet. Most of the time they were just old farm trucks and never saw much over 40mph, not much noise at that speed. they can do more with no problem, they just get noisy.
I think Achipmunk may be on to something there with his exhaust question. I had Glasspacks on my old '63 longbed, but the pipes went all the way back. I built that one in the '70's. I built my '62 in this century. It is a shortbed with the pipes turned out just behind the cab, under the side step. Thankfully. I don't have glasspacks any more. I went with Flowmasters this time around.
