Transmission noise

Id check the driveline, yolks, ect in that area. Thats just what it sounds to me.

 

The '07 386, Eaton-Fuller 13spd, I drive acted in a similar fashion this past Thursday/Friday. Seems a bearing is failing. It's in the hospital now getting worked on.

 

Txviking how long has the truck been sitting?

 

What series transmission does it have? All of the 12513's were noisey in those gears because of the course gear cut. It might be any of the things already mentioned, but the first thing I would do is park it somewhere perfectly level and crawl under the truck with a fairly large adjustable wrench and loosen the big plug on the drivers side of tranny, the oil should be even with the open threads, if you have to stick a finger down in it to find oil it is low. If indeed it is low, make sure to add proper lube, it uses 50 weight conventional or synthetic, synthetic will have a unique stinky smell and is a little slicker, if your unsure of yourself get someone who can definetally tell before possibley adding the wrong oil.

 

Sorry I just noticed the 379 picture and description in your post, if this is the truck your talking about it won't have the 12513 unless someone put it in after it left the factory, but lube info is still the same.

 

I'm having transmission noises also its almost just as loud sitting in neutral at park position. Its a lot louder running down the road almost sounds like its about to just bust loose its also a 13spd in a 2002 freightliner century

 

Have you had this looked at and any responses