help makes sound like its a belt but its not a belt

[tiffany760]

OK so I have a 76 350 Chevy 4x4 truck and we are totally stumped on what this could be. When accelerating going say 60 on the fwy it will start making a noise like you would hear from a belt but its not a belt. But then when I take my foot off the gas it will continue to make the noise until it reaches a certain slower speed then stops but if I accelerate again to a faster speed it goes again. Then yesterday it got worse to the point it wouldn't let me drive around town. But once it cooled down it was fine unless I was to go like 60. ( I don't have the speedo hooked up which it why I say "like 60“ just assuming. )

So if anyone has any ideas to what could possibly be doing this let me know.

Also I maybe a girl but I'm not a dummy when it comes to my truck. So please leave the blinker fluid comments out.

Thanks

[Blue Bowtie]

Welcome Aboard!

There are almost innumerable possibilities. It may be an engine related noise, or driveline. A wheel bearing, transmission tailshaft bearing, midship bearing, or rear axle bearing could exhibit those symptoms. Does the frequency of the noise vary with engine speed, road speed, both, or neither?

[tiffany760]

Well I know its not the engine cause we just put a new one in. Everything was going good with it all up until recently.

Answer to your question the frequency of the sound varies with road speed.

Would just greasing up any of these parts help? Cause before me the truck didn't get much attention and sat around.

Thanks

[tiffany760]

Also when accelerating quickly it will make that sound when shifting then go away until we get to about 60 or so mphs

[oldblu65]

Originally Posted by tiffany760

OK so I have a 76 350 Chevy 4x4 truck and we are totally stumped on what this could be. When accelerating going say 60 on the fwy it will start making a noise like you would hear from a belt but its not a belt. But then when I take my foot off the gas it will continue to make the noise until it reaches a certain slower speed then stops but if I accelerate again to a faster speed it goes again. Then yesterday it got worse to the point it wouldn't let me drive around town. But once it cooled down it was fine unless I was to go like 60. ( I don't have the speedo hooked up which it why I say "like 60“ just assuming. )

So if anyone has any ideas to what could possibly be doing this let me know.

Also I maybe a girl but I'm not a dummy when it comes to my truck. So please leave the blinker fluid comments out.

Thanks

Have you recently replaced the tires on your truck ? Tires can be a source of noise especially with some of the available choices for a 4x4 truck . If your previous tires made less noise and it has become noticeable since the replacement , perhaps there is your noise source ? If that isn't the case ( possible recent tire replacement ? ) , then perhaps something in the front end of your 4x4 is showing wear and making the noise ? The extra components of a 4wd truck in the front suspension area include drive axles , wheel hub bearings , universal or CV joints , etc. ! Have all these parts been checked for excessive wear ? There are lots of possibilities for a noise coming from that area . You also should check your transfer case . Most owners of RWD vehicles seldom think about servicing the rear differential and usually they have little or no problem with it . Often they think that on a 4WD truck ( or car ) that the front differential doesn't need service and neglect it . But the front differential has many more moving parts than the rear and they are subject to much more wear and tear than the rear differential . The front differential needs regular maintenance or it will come back and bite you ! There are more possibilities for the noise but I'd check the mentioned ones first . Good luck !