Manual transmission sounds

2000 Frontier w/ 110,000 miles(manual transmission) is making grinding sounds when down shifting from 3rd to 2nd gear. Also, sounds if something is spinning when first started, driven for a few minutes then stops.

When was the last time the gear lube has been changed?

Don’t remember when gear lube was changed. Is this a DIY or will I need to take it to my mechanic?

It’s a tad trickier that a standard engine oil change. The drain plug should be easy to locate on the bottom, but the fill plug is on the side of the transmission and requires a hand pump or a creative routing of a long hose to gravity feed the lube in. Also, you need to check to see if this transmission uses GL-4 or GL-5 gear lube or Mercon IV automatic transmission fluid. The wrong fluid will do damage.

The fill plug is located so that the proper level of lube will begin to dribble out of the hole. If fluid doesn’t dribble out, stick your finger in, and feel for lube. If you feel none, you are low.

For a hand pump to pump fluid in to the hole, I use one of these that screws to the top of a one-gallon jug:
http://www.autozone.com/autozone/accessories/Autotec-Gallon-hand-pump/_/N-26fv?itemIdentifier=940782&_requestid=319153
http://contentinfo.autozone.com/znetcs/product-info/en/US/igs/57429/image/2/