S13 J30 Rear Hub Swap Guide

[Blaqkfox]

J30 REAR HUB SWAP GUIDE

Was in the middle of this "build" and in all my research I couldn't find any good write ups on rear J30 Hub swaps, just comments that "yes J30 will work. bolt on and go. plug and play.". But it isn't, so I thought I'd make a detailed write up to help clear things up. This is a rough guide. You're application may differ. This is only my 2nd 240 so if you have any input I should edit let me know!

Let me start off by saying I am not familiar with the stock bolt size for the traction arms,. All of mine were aftermarket and came with this car when I got it. They were 17 and 19mm nuts/bolts.
My suspension is also on coilovers, and I believe I read somewhere that you need a strut with a different style hub mount than stock. The J30 Hubs have an extended large dowel pin like thing thats been bored out and tapped for a bolt, forgive me idk the technical term for it, but it slides into the strut eyelet which has a welded in washer on the backside which a bolt passes through to hold it all together. Also note when I installed new J30 bearings the hubs started to bend where the E-brake shoes mount/dust shield when trying to press the old bearings out. I was able to beat them back into shape and work but it was a pain so be careful!

THE J30 HUBS





YOU CAN USE THE 240 AXLE
and you should. The j30 axle is longer. and some j30 axles are not the same 6 lug bolt pattern to the diff. I am running a 95 6 bolt J30 differential in my application (because it has the 6 bolt output shafts which match my stock axles), and J30 rear hubs and Front J30 hubs, but theres already a detailed write up on those. Now I did notice one other thing, I bought these J30 rear hubs used and I read in other threads that you have to modify the lower ball joint mount by grinding it down, and it appears someone had already done this to mine, it didn't seem like they had to grind much but idk what they look like stock so AS WELL I read somewhere that the spline count is different and you have to use an Schassis hub in the upright. I have not counted and don't know what the s13 spindle count is, I do know the J30 is 29, At any rate for mine there was no spindle play at all. it locked in perfect.

THE PROBLEM

The backspacing on the axle to the hub difference between the models means that the stock s13 axles dust shield will be pressed into the rear hub bearing seal on the J30s hub. The seal is a friction fit so its stationary, while the axle needs to spin. Everything feels fine upon instal but you will quickly discover when you tighten the axle nuts suddenly the entire rear locks up like its in a bind!







Here is one off the axle to show



Which the solution is easy. Just lightly tap the shield off with a hammer.









ITS THAT EASY.

The new Fitment







VIDEO LINK BELOW
https://flic.kr/p/2a4484d

THE NEW PROBLEM
I used B13 Sentra '89 front ball joints on my rear suspension arms but it seems the J30s ball joint hole tapers at a greater amount than the Sentra one does, so theres some play, im talking 1mm or less in diameter. Has anyone ran those on this setup?

Stay Tuned.

[PapaSmurf2k3]

Thanks! These pictures are much better than the ones I saw in the other thread

[Hijacker]

Great write up!

[Blaqkfox]

Glad I could help! Ill update when I get the lower balljoint figured out. idk if this Sentra front B13 one will work or not, it seems like its taper is less gradual so theres an increasing 1-2mm play it seems... I looked up the J30 ball joints at work today and im thinking I could just use those. the control arms between the J30 and 240 look very very similar so im hoping so, gonna grab one and test it against the Sentra one... ill let y'all know!

[Blaqkfox]

so update, the B13 (1989) Sentra front lower ball joints do work, they fit perfectly with the exception of a 1mm or less play between the snap ring and the lower control arm, but thats ok, the important thing is that the tapers will fit together and still allow the ball joint to move how it needs. I cut the rubber completely off the ball joint I got mad and cut off under the nut lol and it fits snug as bug. so thats it! I picked up a new ball joint today at work and ill install them in the morning and that should be that!

[HollywoodJackson]

Let me get this straight, because I am impulsive, and will run to PickAPart FAST and buy the wrong hubs, LMAO.

The '93 J30 front and rear hubs work on my '90 240SX, and give me a 5 lug solution?

Thanks.

All the best,
~HollywoodJackson~

[Blaqkfox]

Let me get this straight, because I am impulsive, and will run to PickAPart FAST and buy the wrong hubs, LMAO.

The '93 J30 front and rear hubs work on my '90 240SX, and give me a 5 lug solution?

Thanks.

All the best,
~HollywoodJackson~

Sorry for the late reply, but basically yes if you get any j30 rear hubs they'll fit on the s13. you have to get the whole piece not just the wheel bearing / 5 lug end but the entire hub that the control arm links bolt onto. its a press on bearing unlike the S chassis and z32 which are bolt on wheel bearing/hubs.

Also for the front I was running the J30 hubs on s14 spindles. but one of mine felt loose so I went back to s14 hubs because its cleaner and easier imo. S14 front hubs are pressed in wheel bearings that are non survivable (you can't buy new bearings and press them in, you can only buy new hubs). the J30 does have pressed in bearings in its front hubs as well but they are serviceable. so when putting J30 on S13 you can press the S13 bearing into the J30 Hub. for S14 you can just use the J30s bearing as it fits the larger S14 spindle diameter. But for both you must cut the ABS ring off the J30 front hub and place a thick washer behind it with some shims to achieve proper fitment. theres a great write up on Zilvia for it on an s14. also if you press the S13 bearing into the j30 hub it covers up the snap ring recess groove. being the nut holds it all together anyway most people just don't worry about it, others have a new groove machined to relocate the snap rings position. you can see why I went back to s14 hubs on the front... As well FYI if you end up trying to 5 lug swap from an S14 and are using s14 front spindles like I am, you will think the s13 ball joints are tight but they are not. the taper is different between the s14 and s13 spindles so you will snap s13 ball joints if you run them in s14 spindles. you can order Moog ball joints for an s14 and press them into the s13s lower control arms or if you are already running extended lower s13 control arms you can swap s14 LCAs in, though I have heard some people complain it messes the suspension geometry up (but I believe this is due to the s14 arms being longer, so yeah you'll end up with massive camber, so again if you're already running extended s13 arms try some s14 arms, or just swap ur LCA ball joints). Another issue is the bolt holes on the s14 where it mounts to the shock are larger, so you will need inserts in the s14 holes for the smaller s13 bolts or you can use larger bolts and drill the shock mount holes out a bit.

basically TLDR: yes J30 bolts on the rear of S chassis. The front has to be frankenstein'd and you're better off to just buy s13 aftermarket 5 lug hubs for the front. or possibly go s14 spindle by modifying the shock mounts, and swap to s14 LCA ball joints.

hope that helps!

[Blaqkfox]

OHOH OH!!!
ALSO~ you must grind down the lower ball joint mount on the rear j30 hubs cuz the s13 lca ball joints are too short to get a nut on!!! and make sure you take the dust Shield off the axles like im talking about in this post! also I heard talk you have to change the way the shock mounts on it as well, but I didn't have to, I think my coil over design allowed me to simply flip it around, but I bought these used off a guy that supposedly had them on an s13 so most of it was already done on the rear for me....

[golgo13b]

If I find a whole J30; are there any other parts i should take for an s13 other than the Diff & Hubs?

[Blaqkfox]

If I find a whole J30; are there any other parts i should take for an s13 other than the Diff & Hubs?

make sure the diff has the 6 bolt flanges for the axles if you want to use oem S chassis axles (you simply need to remove the dust shield off the axle with a little hammer tapping). You will also need the rear casing of an s13 differential to swap over to the j30 so the j diff can mount in the s13 subframe.

the j30 rear hubs are direct bolt on swap almost. the mounting hole for the lower ball joint has to be ground down a little bit as its too tall. the hubs have the same spline count as 240 so the axles work. replace with new j30 wheel bearings if its bad. only downside to j30 is its wheel bearings are press in not bolt on so it is more work so id recommend just getting new wheel bearings while its all off. Like Z32 you will need new E brake cables.

The front J30 hubs will work on S14 spindles with the j30 bearing but you must cut the ABS ring off the hub and remove the rear seal, then use a thick washer and spacers to keep the hub spaced off the spindle enough it doesn't rub. I also found out when doing so the J30 hubs are longer than the s14 hubs by a good 6mm. I went to Lowes and happened to find a steel plate in the bin that was 6mm thicks. I simply cut out two rectangles and drilled holes to make a caliper spacer. grab longer caliper mounting bolts from a hardware store that are about 6mm or so longer as well to make it all work. keep in mind this will also push the front wheels out another 6mm!

The front J30 hubs will also work on s13 spindles. you do the same as for the s14 but ALSO you have to press in a s13 wheel bearing. the OD of the s chassis bearings are the same but the ID of the s13 is smaller than the s14 is why this works and needs to be changed.

You may also want to rob the calipers and rotors too btw, the j30 brakes are the same size as the z32 brakes they just don't say Nissan and aren't top load. oh and also they're two piston not 4 piston but I mean for what most do you'll be fine with it. its basically a poor mans z32 swap.

All in all it turned out I have s14 front hubs and the downside to j30 hubs on s14 is that the bearings on both j30 and s14 are non serviceable up front. So unlike the s13 where you can just grab a new bearing and install it, on the s14 and j30 you can only buy the hub assembly with the bearing already pressed in so if you're j30 bearing goes out on an s14 spindle like I have you have to do the whole mod over again rather than just service it. I have s14 spindles on my s13 so to save the headache later on I went ahead and pulled my J30 hubs back off the front and went back to s14. that being said I have two j30 hubs here with the washers and shims ready to go on s14 / s13 if you press in bearings/ if you need them. located near Seattle WA.