Mysterious drivetrain sound

[tonyg2781]

Hey Guys and Gals,

I have a unique situation on my 2000 4Runner SR5(automatic). I want to preface this inquiry by noting that i have had a radiator blow which caused water contamination in the tranny. I flushed it by removing the return line (recommended by trans tech) and running about 20 quarts through it. The fluid looks just fine, The transmission shifts just fine and there is no slippage.

Upon acceleration from a stop, there is a "fluttering" sound, kind of like baseball cards in a bicycle spoke until 30 mph is hit, which is right about when the tranny shifts into 3rd. I can actually feel a bit of feedback of this in the accelerator pedal. When approaching 30 mph (around 25 mph or so) the sound cuts out once or twice and then goes away. The sound never returns again until the vehicle falls under 30 mph, and it only occurs when the vehicle is in drive and the vehicle is under accerelation.

I think that it is either a issue with a clutch or something with the driveshaft. I am pretty experienced working on my own vehicles and worked in a body shop for quite some time. This one has me stumped.

Has anyone experienced this or have any ideas?

Thank you in advance,

Tony

 

[mikestang]

Hmm, could it be something in the torque converter is loose, and you can hear it fluttering until the TC locks up? A messed up clutch plate in the gearbox wouldn't make any sounds like this if it were slipping, it would just slip and that you would notice.