I have an '88 with a 4.0 and a BA-10. I am hearing a knocking at first acceleration, at first I thought it might be the drive shaft u-joints. Then I noticed it will occasionally happen while at a dead stop. It sounds kind of like something bouncing. Any ideas? Possibly the clutch or throw-out bearing? Help. Thanks.

is it a knock from the engine? or somewhere else? if its from the motor, it could be lifters

No, it is definitely not an engine knock. I am not altogether sure that it is not coming from the t-case. It feels like it is under the floorboard on the driver's side. That's why I am thinking clutch or t-case. Anything in the t-case that can feel like it is bouncing on acceleration and at a dead stop?

when i accelerate to hard i have a loud clunking noise. been there for about 6months. just changed out the Exhaust header and realized its the dang motor mount on the left side. so i replaced it. mine had no more rubber in it just metal to metal bangin around. it not longer does that now. so check the mounts. now when you stop it could be just the engine settling?

Thanks, I'll give that a look tonight.

Motor mounts??? I completely destroyed mine over the Summer, and it felt/sounded like it was coming from underneath my feet. I hunted down u-joint play, loose calipers, steering likage, LCA mounts, all kinds of crap... then it hit me like a stoner on a bong - MOTOR MOUNTS!

Well thanks for making me look in the right place. It ended up being the front exhaust clamp. It was on but not tight. when the engine would lug as you accelerated or the engine vibrated during idle the exhaust would rattle in the clamp and it would magnify through the trans and up to the frame. Ahhh one mystery noise down a couple to go.

Glad you found it, and glad it was something simple.

This is gonna sound odd, but i had a ticking under acceleration/load and i thought it might be a lifter or somthing. I changed the transmission fluid and the sound went away. It would only happen accelerating

just another idea