Im thinking about a gear change on my 12bolt. Its a new moser full 12bolt rear with the 33 spline axles and Eaton posi. What are my options, as far as spring pressure in the posi. And is this something I could change myself? Is the next size spring to aggressive for the street? Whats available and who's gears do you recommend?

Thanks Rich

Do you know what series the posi is? If it is a 4 series then your gear options are limited. If it is a 3 series then you can use anything from a 3.08 to a 4.88. I use a lot of US Gear and Motive Gear. Precision and Richmond are also good, but I don't use them as much. As for the springs, you can use 200, 400 or 800 pound preload springs. You must get the right plates to go with them. The 800 pound springs will break the 200 pound plates in a hurry. Do you know which springs you have now? The 200 pound springs are easy to install, and the 400 pound springs are not too bad, but the 800 pound springs are a real pain to get in. If you have the carbon fiber lined clutch plates you shouldn't use the 800 pound springs. If you have the 22 plate clutch set and you want to do a lot of street driving you should change them to the 18 plate set. The 22 plate set has thinner plates that don't hold up as well with a lot of street use.

BGH,

Its a 3 series, I believe the 4.11s are the thick style to fit the 3 series diff. I have no Idea what spring pressure is installed in the posi. I really want the diff to grab hard at the track but I do drive it on the street. Im thinking 3.55s. Is there a way for me to Identify the different springs used from the outside of the diff. Perhaps you could give me a price on a 3.55 gear set, my email is ragtp@optonline.net Thanks for the help-- Rich

The 200 pound springs are green and the 400 pound springs are yellow. Most of the time the 800 pound springs are red, but I have seen them other colors. The 3.55 gear is expensive, but the 3.42 is a lot cheaper. I'll send you some prices.