I have 1998 50th Anniversary Edition Lariat with an 4r70w automatic transmission. Here lately my truck has been crying a tune and I don't know what could be making it do it. I am going to change the trans. fluid and see if it helps. Then again it may not even be coming from the transmission. I hear the noise when I accelerate. When I take my foot off the gas, I don't hear the tune anymore. Has anyone else had this problem?

 

sounds like a driveline noise,check your u joints, also check rear end oil. mine makes same type of noise. previous owner replaced u joints and my rear end oil looks ok so.. i am running bigger tires so thats makes some noise also..

 

Thanks, I sure will check that out. What size tries are you running?

 

Check the oil level.

 

there only 235/ 16 which isnt really that big but enough to make a little noise.