NA/NB Front ABS Hubs, 2 Parts Numbers???

[Luke]

I am up for new front Hubs again after only 16 months of the so called "better" re-packed blue printed ones that had the ARP studs. I had grease seeping from these from the 1st track day.
OEM originals lasted from March 2004 to May 2015 with a lot more track days in that time but with original Shocks and Springs.
I am inclined to go with originals again with a bit of Apples and Oranges comparison going on just to compare how I go again.

My problem is that there are 2 Parts Numbers listed for ABS Hubs. Does anyone know the difference between the 2?
I am using Arlington Mazda as an example here but all US Mazda dealers seem to offer the 2 parts numbers for ABS Hubs which are also searchable on Amayama.
NA23-3304-XA LINK
NA23-3304-XC LINK

As far as I can tell they are the same except that everyone wants to charge a lot more for the C Model with no explanation other than they are for 8th January 04 build date onwards???
I thought there were only 2 types of NA/NB front hubs that were identical other than the ABS ring for the ABS model, interchangeable in other words.

And yes I know you can move the ring across from a ABS Hub to a Non-ABS Hub. NA01-33-04XA LINK But I can get the XA ABS model cheaper then the Non-ABS model.

[Luke]

I got a response from Rosenthal Mazda.

I looked at these two together and could not see any physical difference. You will, of course, use at your own risk. Also, if you purchase any item not for your model year there is no warranty.
But I see no outside difference in the two.

Like I thought.
But seriously does anyone know if there is a difference?
Just seems a bit odd that a different part number exists just when they start selling Turbo models. Better grease and bearings???

[Luke]

Note that my 1st post has a mistake.
The US date standard caught me out. 08/01/2004 = 1st of August 2004 not 8th of January 2004!!!

After random researching every now and then, I have found the answer as to why there are 3 front Hub part numbers for NA/NB MX-5's on various US based websites. I also found out that there was another part number as well that was discontinued.
The bulk of the information came from these threads.
Mazda-speed.com LINK
Mazda-speed.com LINK

This is important for owners of late model NB8B's or SE's in Australia assuming we got the same build specs as the US but could also affect all NA/NB's with ABS.

Front Hub Parts
Part 1: NA01-33-04XA
Front Non-ABS Hub. Fits All NA's and NB's but you will not have ABS unless you fit a ABS ring to it.

Part 2: NA23-33-04XA
Front ABS Hub for all NA and NB MX-5s up to build date of 1st of August 2004.

Part 3: NA23-33-04XB
Front ABS Hub for all MX-5s for build date between 1st of August 2004 to 1st of February 2005.
This part was replaced with Part 4: NA23-33-04XC

Part 4: NA23-33-04XC
Front ABS Hub for all NB MX-5s built after 1st of August 2004.

There are also 2 different Sensor rings.

Ring 1: NA23-33-471B
Up to 1st of August 2004, Outer Diameter is 3.250"

Ring 2: NA23-33-471C
After 1st of August 2004, Outer Diameter is 3.330"

The inner diameter is the same for both. So this means the ring is interchangeable.

The sensor on the car must have changed as well.
The Americans report that the larger ring will rub on the older cars sensor and the smaller ring is not close enough to the sensor to work on the newer cars.

The Americans say you can't just buy the rings for the later models, but putting the part number in Amayama, they show up.
Either way try to keep your standard rings on either model as long as possible by transferring to your new hub as they are worth about $50 each from what I can find.

[zossy1]

You want Timken 513155. They come with new rings. I buy mine from rockauto but with the AUD in the toilet you may be able to do better locally.

16 months isn't bad... Don't expect more than a season or so from front hubs with high grip tyres in a track-driven car.

[Luke]

You want Timken 513155. They come with new rings. I buy mine from rockauto but with the AUD in the toilet you may be able to do better locally.

16 months isn't bad... Don't expect more than a season or so from front hubs with high grip tyres in a track-driven car.

Yes, I know of that part number.
But it will not work for people with 1st of August 2004 onwards from what I have found out.
Good thing mine is a February 2004.

Another issue to keep in mind with aftermarket hubs is will the standard ABS ring fit?
A lot do not have he same diameter mounting face as the factory NTN Hubs to fit the ABS ring.

I'm not running R-specs or Slicks.
That's why I am concerned with the premature failure of my front right hub. Left is fine.

[Luke]

My edit time ran out.

In regards to longevity of the hubs.
9 Sprints between Wakefield and SMSP Variations. About 5 sessions at each event.
1 Club Day at Wakefield in the wet. 4 Sessions.
2 Marulan Days. 4 sessions at each event.
And only 1 off track excursion which was rear first in the dirt at Turn 9 at Wakefield. So I have not had to many big impacts on the hub.
I had old hard compound Kumho V70'As for the first 3 sprints and the 1 Club day which had no grip.
I had Hankook RS-3's which are more sticky then those Hard Compound V70A's for all the rest.
That's why I am concerned with the "premature" failure of my front right hub after 12 goes.
Left hub is fine.

My OEM hubs went through many more Sprints, Marulan Days, Club days, Road Driving etc.
I can tell just by how many sets of tyres, Factory Toyo tyres, Achilles 123S, Kumho KU36, Toyo R888 and 2 goes on the old Kumho V70A hards.
Yes those Kumho V70A's only lasted 5 goes, they fell apart being old.