Strange neutral sounds???

Hello ,
When I put my S10 in N, it makes a funny sound like something vibrating or loose, Does anyone know what might cause this? It doesnt make this sound if its in gear, basically its when Im about to park the truck. Is it normal if it make some noise in Neutral?
Its a 2001 S10 Ext Cab 5 Speed with 29,500 miles on it. Also the Service engine light just came on, is there any place i can get it checked for free?
Thanks

describe the noise better. what kind of noise? metal to metal, clunking, ticking, tapping. does the noise go away when you push in the clutch? i believe pep boys will scan your computer at no charge.

Probably a grindin noise.

Have your manual tranny fluid checked and make sure it is up to level.

Also, AutoZone checks the codes for free.

Thanks its more of a ticking or loose metal sound, but it goes away after I warm of the truck .

You sure it isn't from your engine?

What if you put it in gear with the clutch disengaged, does it go away then?

The one thing is, nothing is moving in transmission when you are not moving.

if your engine is running and your clutch is engauged in nuetral the only things rotating in your tranny is the input shaft, intermediate shaft, and all the disengauged gears. if your hearing a noise in the tranny (i assume its the tranny) i could only imagine it would be gear noise or bearing noise. drain your trans fluid and make sure there are no metal particals coming out. and of course make sure it is at the proper level. do this check first! start your vehicle. when you say it makes the noise then put it in nuetral and push in the clutch. if the noise goes away it is most likely in your trans or clutch system. when you disengauge the clutch there should be no rotating/moving parts in the tranny when the vehicle is at a stop. that will narrow the noise down to the tranny or the clutch sytem. good luck!

Tranny fluid just might be low.

ill try those thanks