i have a 2002 6 speed, and coming up on 25,000 miles.

2 questions.
how often do i have to change the manual tranny fluid?

and since i'm changing it to MT - 90, do i just drain and fill??? or do i get a tranny flush which costs alot of money.

 

Nissan recommends every 30k to change manual transmission fluid.....But just to be on the safe side....I do my changes at every 15k.....becuz everytime i drain my tranny fluid, its very dark and smells pretty burnt up......

Ice2k1 (alex) changed out his mt-90 at 20k miles and reported very dark color and a harsh burnt oil smell.....he recommends people changing them at 15k or less becuz of how quickly the mt-90 wears out.....

even if i'm wrong on this one....i'd still change out my fluid just to be on the safe side.....its better to change it out to fresh new one.....than to run a few extra thousand more miles and save almost nothing, becuz you still have to change it out anyway.....i'm very **** about not changing out my fluids on time.....

 

so should i get it flushed??? like go to nissan and pay 160 for a machine flushing......

 

I think you can just drain it... but wait for someone else to confirm this, or check the Fluids and Lubricants forums for more info too.... I'm sure this is asked there a lot....

 

You can refill with fresh fluids (perhaps add some additives oil) and drain it out again. There is no machine to flush out a manual transmision fluids, I don't think.