Hi All,

I've owned my box for a few years now. But in all this time I've always wished there was a 6th gear or that the 5th gear was better sized for lower rpm's and higher MPG. At 70mph it's at 3500'ish RPM's (don't get me started at 80mph and 4k rpm area) and just seems to high compared to other cars I've driven or been in at that speed.

Say for instance 2013 Honda Civic 4 door is at say 2200 at 70 mph. Or Ford Focus 4 door is at 2500 rpm at 70 mph. Both cars 4 cylinder cars. Both a lot quieter and better gas mpg. Don't get me wrong I love my box. I'm just looking for that transmission mod or aftermarket part that provides this option.
That 6th gear would be nice

 

toyota echo transmission will swap in. but our cars are geared for city driving not so much highway driving...

 

there is nothing you could do to the transmission that would pay dividends in any reasonable amount of time.

So unless you can get parts for really cheap and do the labor yourself, it is pointless. You can either do what JCT said which is swap in a transmission from a toyota echo, or change the final drive ratio to a taller ratio for better gas mileage.

 

I want more mpg so this is my plan swap my xa final drive form a yaris 2006-10 one, After that it should be running 2500 rpm at 60 mhp aprox.

output shaft 3332152081

diff ring gear 4122152280

I'm not pretty sure if I'm correct but this guy already do it to a yaris using xb 1st gen parts just to make it faster for dragging.

xB final drive swap thread - Toyota Yaris Forums - Ultimate Yaris Enthusiast Site

 

Keep in mind, you might not come out ahead at all as it takes more power to drive a taller gears so you might end up in the same boat you started off of.

 

hi guys,


I have been searching for automatic transmission swaps that yield a higher cruising speed and better mpg's.


with my 2006 xb with automatic transmission.. I am currently getting 31mpg here in California.. that's with the a/c running 90% of the time and hauling around 200-250lbs of car parts. I drive 80-90% of the time on the highway/freeway.


my current highway/freeway speed is 65-70mph... I use my xb to ship aerokit parts I make for mr2's.


the info on the net has info regarding manual transmission swaps or 5th gear swaps for the xb.


I have an automatic and want to stay automatic.


to increase my mpgs I went from 28psi tire pressure to 32psi tire pressure.. I say my mpg's increase. from doing more reading I found out that for hypermiling 40psi is recommended(on stock steelies and tires).


like I posted above, I am staying at the 65-70mph cruising speed but normally I drive around 75(I am in the los angeles area).


my car is completely bone stock.. this is the first mod I want to execute.


your help will be greatly appreciated and I will document my experience for others.