Idler arm and pitman replacement

was told i need an idler arm and pitman arm,
since my truck 2001 chevy tahoe 4X4 is not very
stable on the road ,the question should i change tie rods too inner outer,thhey said they are fine,
i remeber we change all together,
canu help plz

thanks
frred

I would replace all related components at one time and get it aligned to prevent from having to do it later.