Since I have a 91 305 TPI and am not planning on getting a 350 I think it is time to change gears. My question is this. Would it be better to just buy a complete unit from eaton or powertrax or just buy gears and pay to have them installed. I think it would be less money to get a complete unit and do the work myself. If I am right then with the complete units I just slide the axels out and put the unit in then put the axles back in. Any body have any insite on this. BTW the powertrax and eaton units in Summit are around $430.00

 

basically you're correct. you can just swap your ring gear to the new carrier and check back lash and contact pattern and be on your way. however if you wanting to change gear ratios then you need a new gear set but not a new carrier, unless you're wanting to upgrade to a posi unit at the same time. installing gears isn't that hard or take very much time but it does require tools most people don't have around the garage. look in your manual at the rear end section to get an idea of what's involved.