The truck is a 99 Tacoma v6 auto 4x4 extended cab w/trd. It has 206k miles and is in very good to excellent condition. When I let off the gas at any speed over 35 it has a strong vibration. As it slows down to 35 it stops vibrating and if I put a slight pressure on the gas pedal it goes away. If I shift into N it does not go away. The fluids are at correct levels and have been changed per the maintanence schedule. I have not offroaded it recently to bang up the driveshaft. What do you think it might be?

 

Check your ujoints.

 

Or ball joints too

 

I've had this happen before....was the carrier bearing on the drive line.. hope this helps...

 

The u joints seem ok and I lubed them except one which has the nipple aimed to the center of the joint. I need to get that turned to lube it and it is way over due. The vibration is less now, but still there. How do you know if the center joint is bad?

 

Unload the drivetrail, usually on jackstands. Put in neutral and put xfer case in neutral, and get to shakin and wigglin. You can't properly test a ujoint without unloading the driveline first either. May seem fine on flat ground, but could have a hitch in it still.

 

and if a ujoint is realy dryer than a popcorn fart you somtimes wont feal any movement the best way to ckeck is pull the driveshaft put it in a vice and check for stifness wobble or play you also need to check the stub and yoke if you have cv style. the play in the middle of the shaft [hyoke] fianly if thats not enough you also need to ckeck the run out for straightnedd more than.005 degrees then the shaft6 is bent witch caulses pemature ujoint failer you guys se my name 20 yrs exp

 

I'd recommend listening to this guy ^

 

lol i'll give you the shaft and you'll love it

 

I had a similar problem on my 95...it ended up being the bolt that holds the companion flange (i think that's what it's called?) onto the transfer case. That's an easy thing to check. There's another bolt on the other end in front of the diff that's known to come loose. Also if you wanna isolate the problem to the rear, take off the drive shaft and drive around in 4wd for a while.

 

Thanks for all the replies. I jacked it up in neutral and I found the last u joint before the axle had play in it. It was the one I could not grease. I replaced it and the vibration is gone.

 

Well what a happy ending.