nissanfanatic

I know this information is available through searching, but I wanted to make an easy-to-find thread with clear and concise information for future searches.

This is a bad hub(the cut is from previous removal of the outboard inner race of the wheel bearing):


This is a brand new good hub:


This is a side by side:


What to note to decide whether or not to reuse your old hub:

• Notice on the bad hub the distinct difference in finish. This is not normal. The line is definitive enough that it could be confused for a machining line. That is from the inner inboard race seizing and wearing the hub down. Your hub will wobble a little in the new bearing and just destroy it in little time.
• Check the actual surface that the wheel mounts to for cracks. I recommend using a magnifying glass or corrected vision to closely examine it. Our hubs are very thin.
• Measure the entire press-fit portion of the hub; the part that presses into the wheel bearing inner race. It should measure 1.770". If not, it needs to be replaced.

The difference in texture and appearance of the press fit portion of the hub should be evidence enough, but a thorough inspection and measurement should be conducted IMO.

If you reuse a hub that is not within spec, expect to replace wheel bearings at least once a year if not once every couple of weeks. Eventually, you will end up replacing an axle. I had the threaded portion of my stub axle break off during a retorque attempt. This would be a very bad failure on track.

Credit to DanielZan for pictures:



Attachment 133485

This is exactly how the axle will fail. It will occur because of a very slight (thousands of an inch) wobble that occurs between the hub and wheel bearing inner race. This cyclic stress repeated over time will eventually result in the failure of your stub axle.


I hope this helps someone in the future.

Elistan

Hehe, you (or DanielZan?) are the only other person I know of with a failure like that.
Fortunately for me, it happened in the garage, not on the track.

nissanfanatic

Mine actually happened after a 450 mile drive. My wheel bearing started making noise about 220mi from home. I decided that I would retorque it once I got back into town. Once I tried to retorque it, that happened. I am so glad I didn't have some catastrophic failure on the highway coming back...

I don't think it is possible to overtorque that nut unless you have an extremely long lever along with being extremely tall, or if you have some sort of industrial impact gun. I think the failure occurs from driving on a bad wheel bearing or hub for extended periods. The slight wobble over time just fatigues the metal.

dwight

This is why you need to make sure you have those axle nuts torqued properly (150-180 ft-lbs + 60-70 degrees, or 380-400 ft-lbs). I have a Rear Axle Nut TSB - DIY for it and pictures of used but good, and a damage hub in the 2nd post.

Good used rear hub (1.770" diameter)

Damage used rear hub (1.763" diameter)

nissanfanatic

Yea, I saw those pictures as well. I just wanted to make a thread that was easy to find. Thank you for posting up!

zeroptzero

How many miles on the setup when it gave out ?. My car has gone 55k miles on the factory torque setting before I was able to correct the axle nut torque to the proper level.

Billman250

I have done the "tsb" to cars with 80k, and caught it in time. If the car is driven lightly you may get lucky.

Any type of corner carving with the s2k and improperly tightened axle nuts will waste the bearing and the hub in no time.

I have also put hubs and bearings in cars with as little at 25k miles.

I put a FOURTH bearing (first for me) on the right rear of an s2k yesterday. Prior mechanic never changed the hub.

beezlebubba

Billman torqued my Rear Axle nuts this past summer. I had just over 100,000 miles... I guess I was one of the lucky ones. car is a 2004 and its still fine

dwight

'04 with over 90k when Billman did mine a few weeks ago.

zeroptzero

Thanks for the replies, that sounds good, reassuring to know many cars can still be saved.

My only concern now is that I did it under the previous discussions and TSB recommendation using 240 ft lbs, the axle nut moved maybe 25 degrees ?. Time to pick up a 3/4 inch breaker bar, lol.