IIRC the fourth gear is the weak link in the six speed equation.

Since the five and six speed transmissions share the same housing, Mitsubishi had to make the gears in the six speed smaller to fit in the same housing. This reduced the amount of abuse the gears can take due to the amount of heat that accumulates in the transmission under aggressive driving/power.

Please correct me if I'm wrong here.

 

I have an Evo X and i'm always looking for the 6th gear I wish it had for cruising. 75-80mph highways speeds are pretty up there in the revs haha.

 

im 400+ with no problem

 

Don't listen to this guy, he's on the 6-speed hate bandwagon . There are countless 6 speeds over 400whp.

 

thank you to the OP for asking this and thanks to you guys for the great answers, im buying a MR very soon

 

I saw mayn people having over 400hp w/ 6 speed sst transmission.

 

i've had two evos mr..on my first evo i had to replace the transmission twice, due to aggressive driving... i was doing close to 400 whp on that car...yesterday i broke another 6speed doin a little over 400whp.. now im getting the 5 speed..thats the way to go ))

 

Everyone keeps on throwing out the 400 number, but let's bet serious - a FP Black is going to put you in the 500 range. Will a 6 speed handle a black or ATP GTX3582r?

 

i put 100k miles on my '05 mR without a problem. ever. freeway driving is better also. its just a bit notchy when its cold...

 

It will handle it if you baby it... But don't suprised that you'll end up buying a new better transmission becuase the stock one couldn't handle it