5 speed manual trans in 04 sierra 2500HD

[CraigThacker]

I have a 00 Silverado 2500 6.0L 5 speed 4x4 and sometimes while driving when changing to 3rd gear it’s makes kind of a grinding sound and quits pulling but I can put it in 4 low and take it right back out and it will pull again until I shift to 3rd can someone tell me what’s going on?

[davester]

The synchro or 3rd gear is shot/worn/damaged?  Or perhaps the shift fork is worn?

[CraigThacker]

When it does it in 3rd gear it won’t pull in any gear even when I put it in 4H but when I put it in 4L it will pull in any gear even 3rd and when I put it back into 2H it will pull until I take it out of 2nd gear so could that still be the issue or something else?

Edited June 22, 2020 by CraigThacker
Left something out

[CraigThacker]

18 hours ago, CraigThacker said:

When it does it in 3rd gear it won’t pull in any gear it kinda sounds likes something spinning and rattling like grinding sound inside the transmission and it always grinds going into 3rd unless I wait for the rpms to lower and the truck will pull in any gear until I let off the gas as soon as I do it makes the noise and will do it until I’m completely stopped but then I can put it in 4L and take it straight back out and it will pull again until I have to let off the gas 

      Does anybody know what’s going on and if it’s something simple I can fix or do I need to look for another transmission?