My 12 bolt posi (Chevy) needs rebuilt. Which of the kits available are the best? I have read some negative stuff on Richmond gears. Is there a best or some to avoid? Also, I read that going to 400 pound springs in the posi are an option, but I believe stock was 200 pound springs and they worked well. Any thoughts ?
It’s not so much the kit,it’s the brand of bearings in the kit. The Richmond kits did have Timken,but not sure if that has changed. The Koyo brand is a good alternative. As far as the posi unit goes,if it has the good clutches,and is tuned properly,it won’t need the springs at all. The originals are 400lb,and there are 600 and 800lbs available.
Gary, A lot of these choices are for you the customer to make in to how you will be using your vehicle and if your going to drive hard a little more preload spring can keep the clutches engaged in all areas of driving... which can be good and bad. Bearings if you stay with Koyo or Timkin you will usually be good. Old OEM bearings from Hyatt or Bower are good too. You really need to open boxes with National and SKF they are a mix of many nationalities of bearings. Remember tuning the clutches in the Eaton will give you different grip and slip again depending on if you are road racing drag racing street strip burn out machine etc. There are steel clutches, composite, and carbon fiber 18 plate 14 plate 22 plate... EATON posi units are like the Holley carburetors of the differential world...VERY tunable Jim JD Race
