Driving at 55 MPH
 

I do not mind driving my truck at 55 MPH but the noise is driving me crazy!
I satarted the Dynomat thing and it has gotton a little better. I seem to be getting most of the noise from the engine. I have a 292, 4 speed trans with a Eaton HO52 rear end.
The noise is especially bad when I close the windows. I am considering installing a hood insulation to tame the beast. Will this provide releive?

Re: Driving at 55 MPH
 

Is the exhaust hanger connected to the cab? Do you have a tailpipe or a turn down behind the cab? Sounds like somethings touching or attached. All the holes in the floor are blocked?

Re: Driving at 55 MPH
 

No, it is none of those things.
All new exhaust, clamps etc...
It seems to be a insulation problem.After installing the dynomat things got better. The truck is all metal in the interior so sound control is a problem.
I am thinking of installing this http://shop3.mailordercentral.com/su...ts.asp?dept=17

Re: Driving at 55 MPH
 

I helped install Dynomat and the foam in a 31 Chev 5 window coupe, It wasn't till we installed Dynomat inside of the doors that the sound in the car became reasonable. Seems if you want it quiet inside you have to put the stuff everywhere.

http://lh6.ggpht.com/_jlNKkl-rSbc/TN...0/DCP00866.JPG

Re: Driving at 55 MPH
 

I agree about having to put that stuff eveywhere. My firewall is next. What is the foam that you mention Aerotruck? I'm always up for noise reduction!

Re: Driving at 55 MPH
 

I've been seeing more use of "lizard skin" spray in sound/heat deadening. Not sure how well it works - but I'd be sure I want it for life before I spray it. But the same could be sead of dynamat also... Just another option. Probably messier than stick-on matting though.

Re: Driving at 55 MPH
 

I believe that the foam was from Dynomat as well, but not sure. It was similar to the product in the link in Born Lucky's post above. Installs easier with two people. Trick is to refrigerate the sheets before installing, cause if their warm and touch anything, it's stuck! The 31, left the foam as an interior finish in the trunk. He put a carpet over the trunk floor pan foam though. Don't wear latex gloves when installing, he found out the hard way! :) Dynomat foil to start with then the foam on top. Adds weight though!

Re: Driving at 55 MPH
 

Oh I think I get it. I thought the foam was a product that was sprayed up into the pillars of the cab.

Re: Driving at 55 MPH
 

Lizard skin is the $hit my buddy has it in his 65 and it makes a huge difference

Re: Driving at 55 MPH
 

[QUOTE=Born Lucky;4293968]I seem to be getting most of the noise from the engine. I have a 292, 4 speed trans with a Eaton HO52 rear end./QUOTE]

I'm wondering if at least part of your problem is caused by engine rpm. What gears are in the H052 and what tire size are you running?

Ray

Re: Driving at 55 MPH
 

Are your door seals, window seals - fuzzies and weatherstripping good?

In my experience the most cost effective way to eliminate rattles and noises in an old vehicle is to

1.0 upgrade the stereo and speakers,
2.0 put louder mufflers on.

:lol:

Re: Driving at 55 MPH
 

Yes I beleive that is the problem RPM's. The engine revs alot doing 60 MPH.
Eaton HO52 is either a 4:11 or 4:56, I beleive.
I just want to listen to music and feel like I am not in a drum.

Re: Driving at 55 MPH
 

Well, if you drive at 45mph is it any better? If it is, its simply the engine rpms. Your at about 3,000 rpm at 60.

Re: Driving at 55 MPH
 

Aside from the engine noise, the SM420's can be a little noisy, and the HO52 can be rather noisy too. I'm thinking you have a combination of everything making noise. Aside from insulation your cab, I would recommend looking into lowering your cruise rpm's. Not only will your engine last longer, but your gas expense will decrease.

Re: Driving at 55 MPH
 

Yes,this is the noise!
If I slow down it goes away or should I say the RPM"s drop and you hear lots less.
I am looking into a rear end change( I would really like to keep original But the gas and noise are getting to be a PAIN)for the coming spring.
Do you think if I sound proof the hood and further sound proof the floor it will GREATLY reduce the noise?

Re: Driving at 55 MPH
 

Somethin' ain't right here. I can cruise at that speed in my 60, got a 350 with 700r4 windows up or down, headers with 40 series flowmasters and it really isn't bad. I think you must have some kind of vibration issue. I rember having a 90 with a 350 towing a trailer in 3rd gear from Michigan to Florida and the drone about drove me crazy. Something about pitch as compared to volume, two different things.

Re: Driving at 55 MPH
 

That's the secret ingredient. You have overdrive, so your engine is turning 30% slower.

Ray

Re: Driving at 55 MPH
 

X2 on the Lizard Skin http://www.lizardskin.com/

Re: Driving at 55 MPH
 

Yes, you have overdrive.
I have a 4:11 or 4:56 gears so if I travel above 55 I get high RPM"s

Re: Driving at 55 MPH
 

I think the tranny noise is an issue as well - I have a 350 with the SM 465 in my '67, with 3:73's, and I have a real noise problem as well, even though I soundproofed the cab and the doors - it is engine/tranny noise, and some wind noise. I'm eventually going to line the hood and see how much difference that makes.