i hear this on my 85 truck 22re, auto, efi with 210k kms whenever shifting from a P to D or from P to R. More so, when the ect button power is on. What is causing this? Checked the auto trans fluid and looks fine-not burnt or discolored. Btw, new experience on an older truck cause ive sold my 90. Your opinion will be appreciated!

 

How many rpms at idle? Check the throttle cable, the one that goes to the transmission, may have the pressure set too high.