mic5rbns

I plan on swapping out 3.55s for 3.73s. I would like to do the swap myself. I have a 2005 Mustang complete shop manual. It doesn't look too bad, but I know there are some tricks out there that might make the change out a little more friendly. I have some mechanical abilities, installed super charger, long tube headers, 39# fuel injectors, piggy back fuel pump, lowering spring kit etc. Do I need to worry so much about the back lash on my ring gear, I have 33,000+ miles on my car. I plan on purchasing some of the special tools the shop manual talks about. My speed shop will do the job for 650.

orange04s281

3.73 are awsome on the s197s but i would recomend that you have a shop install them only because if there is a whine after installation then they should fix it for free, i also recommend ford racing gears cause they require less adjustments most of the time.

Bullitt2theHead

Just my opinion: you might be dissapointed in the (lack of) difference between 355 and 373's. Not much more gear. Go with at least a 3.90 for a noticable difference. Just an opinion.

You gotta make sure you have good teeth contact (adjusted with carrier and pinion shims) and good pinion bearing preload (you need a dial style in/lb torque wrench to do it "correct")

If you wanna do it yourself, go ahead and buy a couple extra crush sleeves in case you dont get it right the first time.

Oh yeah-hint-unless you got a badassed impact gun, put the crush sleeve in a press and compress it somewhat close to the height of the old one (but not all the way). And dont just wail on the pinion nut with the impact, do it a little bit at a time and measure your preload as you go along. You cant uncrush a crush sleeve.