Im working on one of the fleet truck. Its a 1999 f350 v10 4x4 with 380k (if I remember correctly) on stock tranny and engine. About a week ago it started to make a sound, almost like a gear grinding while driving around 55mph or at any crusing speed, ive heard torque converter shutter on you tube videos but this dont sound as bad or feels like its vibrating, tranny shifts good and no slip or codes stored (i used my AE scanner) transfer case spins freely and the 4x4 locks are on free position and the drive shaft is not spining while trucks moving( so that deletes trasfer case and drive shaft issue)

Anybody think it might indeed be torque converter shutter at the bigining stages? I can explain the sound better, almost sounds like when your reversing and put it into drive while still rolling back "crrrr" I guess its the sound

 

My truck had a torque converter shudder when i bought it. It would make a grinding noise at around 55 mph also. I had no vibrations, hard shifts or any other symptoms other than the grinding noise. I used a product called shudder stop that I got from the auto parts store for about 10 bucks and 10,000 miles later it hasn't come back. Might not be your problem but for a few bucks its worth a shot.

 

Ill give it a shot, the sound does come from somewhere between trans and engine might be torque shutter, personaly I have never experience with torque converter shutter, so this is new to me.
Thanks again

 

380k on the clock is a lot. Sounds like a rebuild is in order. You could throw snake oils at it or parts, but it may be fruitless. Sometimes it costs less in the long run to fix it properly the first time and save headaches not to mention knuckle bones.

 

Not really, my eo4d has 800k on it. But like mentioned shifts perfect no slipping or problems except that grinding gear noise, this trucks are stock and all have good maintenance on them, and all have after market trans coolers with fans since day 1, thats why they have lasted as long as they have

 

Though I should let you guy that the problem is fixed, installed a new triple disc torque converter and worked perfect, no grinding or weird noises and I actually feel the power is getting to the ground, even with a 2200lb flatbed it does some smokey burn outs
Thanks for the replies guys
God bless yall