Rear End Gear Swap
Time to change out these salt flat gears!.
1-12-2011
The kit came with an optional 9” rear end which was very nice but, it had 2.75 gears and it was open. I wanted to upgrade to a posi and lower the gears to a more usable ratio. As it was, 5th gear was useless and 1st was way too tall for traffic.
First step was to find out what axles I had, 28 or 31 spline. I pulled the passenger axle out and discovered that it was 28. This allowed me to order the correct unit, along with the yoke measurements.
First thing to do was to remove the wheel and breakdown the brakes. After four bolts holding the bearing retainer, a few tugs on the axle and out it came. Being fairly new, it came out very easy. In the past on other projects, I have had to use a slide hammer and a lot of band-aids!
I ordered the pumpkin from TJ’s 610-485-4858 after speaking with him a couple of times on the phone. I highly recommend talking with him if you are in need of a rear end change, he knows his stuff and is more than willing to work with you. I ordered it with 3.50 gears, Trac-Loc and a new nodular carrier. Being Christmas weekend, it took a little longer on shipping, but I did receive it in about a week.
I began by removing both brakes, bolts holding the bearing retainers and then removing both axles. I then removed the drive shaft and wired it up out of the way.
I removed all the bolts holding the main unit to the housing and then took a 2x4 and placed it on the side of the pumpkin. I used a 5lb shop hammer to strike the 2x4 and break the seal loose. Make sure you have plenty of cardboard or other covering down because this makes a big mess.
After completely draining the diff, I positioned my floor jack under the pumpkin section and worked it out of the housing. Be careful because this thing weighs 75lbs and is not flat or balanced.
I then cleaned up the surfaces and installed a gasket that came with the new unit. I used the same floor jack to position the new unit in the housing and replace the nuts. Then the axles went in being very careful not to damage the seals. I finished by reinstalling all of the brakes like they were removed and then filled the rear with friction additive that came with the unit and new 80/90w oil.
All took about 3 hours and was not too difficult.
Being 35 degrees outside, I then took a longer than necessary test drive and love the new gearing. I now can use 5th and the gearing is much more usable.
Anybody need a slightly used 9” open 2.75 pumpkin?