1985 4runner with 134k on the truck. Rebuilt engine 2000 miles ago.
New timing chain kit, clutch kit and head.
Today I noticed a chatter noise coming more from the driver side trans area while in 1st, 2nd, and 3rd. Probably there in 4th and 5th but I haven't got on the freeway today and doubt I could hear it over the engine and tire noise.
The noise slows down and eventually stops when the truck is put in neutral.
The noise can not be reproduced in neutral.
I got under the truck and didnt notice any leaks of any kind.
The clutch fork does wiggle and I can almost reproduce the noise but wiggling the clutch fork. Is the clutch fork supposed to be moveable up and down slightly by hand? Heres a link to the clutch fork play
clatter from clutch fork? - YouTube

Im not sure what the problem could be, but i checked my clutch fork yesterday and tried to wiggle it like you did in the video, but it sits pretty tight, no rattle sounds. R150F transmission.

Your problem could be a bit worned out clutch fork and the tolerances are bigger so it will rattle.

Thanks for checking. Got an endoscope and found out that the clutch fork is not like most that I see on these trucks and part of the clip that helps the pivot ball stay in place is broke. I ordered a new pivot ball and clutch fork. I’ll be picking up a transmission Jack soon too.

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