diggles240

Sep 2 2010, 12:05 PM

google

the info is readily available in multiple locations

RDM_II

 

I spent the last couple hours making the final verification on the fitment of rear J30 hubs, since there seems to be a lot of confusion surrounding them. I also took apart S13, S14, Z32NA, and Z32TT bearings to finalize those details so there won't be any more questions on this topic. We hope.
As most people should already know, the rear hubs are pressed into bearings, these are sold separately when new but in most cases come together when bought used. The hub simply presses into the bearing like any other part of this type. When pressed out, the outer race usually stays fitted on the shaft of the hub, so for a replacement it's as easy as pressing one out and the other in. I had to do this anyway since I had a Z32NA and S14 hub with blown bearings, I pressed them out and into S13 bearings with lower mileage. The shafts are all the same size for S13, S14, and Z32NA, and the bearings are identical other than the flange on the Z32 bearing that's used to locate the Tbolt that secures the ebrake assembly. The Z32TT hub and bearing assembly is useless for all intensive purposes since the shaft and bearing are larger, but I did find a use for the bearing during the process. The S13/S14 bearings do not have the flange required to locate the Tbolt when using the Z32 ebrake, so instead of using Z32NA bearings you can cut the flange off and place it behind the Tbolt, above the S13/S14 bearing. This is good for people who buy the ebrakes bare, without hubs. Strange part here is the NA bearing flange has a single pin to locate the Tbolt, so they're left and right specific. The TT bearing I had was drilled on both sides and the locating pin can be punched out and moved to the other side, making it universal for both sides, since the Tbolt can only go in one way.
Now the J30 hub. For some reason Nissan felt that their existing design wasn't good enough, so even though the J30 upright is identical to the S14 and will bolt directly to S13s and S14s the bearing is designed into the upright and is not directly removable. It's also a different design entirely. The S13/S14/Z32 bearings are large single ball bearings with an inner and outer race, the J30 uses dual roller bearings with inner, outer, and center races. The center race is pressed into the upright and secured with snap rings at either end, the bearings are then fitted in with the races set at each end, finished off with a seal. I pressed the hub out but like the S13/S14 the outer race stayed in place, one of the bearings and the outer seal also came out with it and the race was extremely hard to press off the hub. It's possible to use the J30 5lug hub in an S13/S14 bearing, but the effort involved to press all the J30 hardware off and get an outer race from a Schassis pressed back on seems a little much, especially when you can just use the whole J30 upright instead. Pulling the upper arms to gain access to the bearing bolts puts you halfway into pulling the upright anyway, a few more bolts and the upright is free to be replaced completely. Plus I doubt very many J30 hubs are in bad condition unless they've been hit in the rear end.
So there it is, J30 5lug hubs can be used easily with the entire upright, otherwise the use of a press and a few hours is required to swap races and for the DIYer it's probably more work than they can handle. This of course will only work if using Schassis rear brakes, the J30 ebrake assembly is different from the Z32 and will not bolt up the same way, plus the backing plate has to be cut off if you're going to use a larger rotor, eliminating the ability to attach the ebrake anyway.