Is it always a MUST that you replaced both Outer and inner.
someone suggested that if the outer is damaged,most likely THE INNER ARE bAD AS WELL.

I AM CHANGING MY OUTER.

 

No... if the inners are tight, then only change the outer. The inners are better protected, and tend to last a lot longer.

 

thanks.

 

Btw,how hard is it to remove and install these myself.
I am not very handy,but all I see is one bolt and unscrew the other end,I know i need alignment right after.

 

Paint your threads and the nut with a nice bright color so you can get the alignment close on reassembly. Hardest part will probably be coercing the joints loose. I like those tie rod/ ball joint separators that are like gear pullers. But there's nothing wrong with a pickle fork and a bfh.
I changed my inner at the same time. I wouldn't recommend it unless they're bad, it wasn't a whole lot of fun.

 

In my experience, OUTER Tierod lasts about 70-80K miles.
INNER Tierod lasts about 130-150K miles.

This is because the OUTER Tierod does the work when the car turns R and L everyday.

The INNER Tierod only works hard when the wheel goes up and down (such as going over potholes etc.). Also, being deeper inside, the INNER Tierod balljoint moves much less than the OUTER balljoint.