So how is maintenance handled for the rear hubs and half-shafts? I got a set of rear uprights and had new bearings and seals pressed in and I'm debating on whether I should install them now or just wait until something back there starts to go? The ones on there now have 83K on them and have never been touched. My concern is if a bearing or half-shaft fails at the track and I have difficulty separating the two. I'm not sure I have room in the truck to carry spares of both the uprights and axles. I only have an open trailer, so limited in amount I can bring along. What are others doing/what's recommended? If you had to chose which spares, rear hubs or axles, to bring with you, which would you choose?

#1
Posted 08-12-2017 10:06 AM

Chris
Happiness is a dry martini and a good woman ... or a bad woman.
- George Burns
#2
Posted 08-12-2017 07:30 PM

the rear hubs and bearings are wear items and should get replaced regularly. I do them every 2 years. Sadly I've been in 2 cars where the rear hub failed causing the wheel to depart. One mine, one an enduro team's car.
I had asked my shop to replace both rear hubs and bearings, but for some reason they put one old hub back on after changing the bearing.
#3
Posted 08-14-2017 06:41 AM

- Jim Drago likes this
V2 Motorsports
#4
Posted 08-14-2017 09:53 AM

There is no periodic maintenance on the rear bearings/hubs. Unlike the front hubs which can be repacked, these are not servicable.
replace the bearings when they get loose. Inspect the hubs for wear or cracks whenever you replace the bearing.
After any contact, a good inspection is required. Ralph likes to change the hub after contact. Let your concience be your guide.
Dave Wheeler
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#5
Posted 08-14-2017 02:32 PM

Chris
Happiness is a dry martini and a good woman ... or a bad woman.
- George Burns
#6
Posted 08-14-2017 02:49 PM

How about the axles? Are folks cleaning and regreasing periodically or just carrying new spares? Higher confidence with certain brands? Any difficulties getting the shaft out of the hubs?
At this point...any oem axle that is still in its original hub will more than likely come out very hard or very very very hard Very unlikely something you can do at the track!
If the axle/hub have ever been apart...especially by a racer, It will most likely have grease or anti-seize and fall right out!
I cant speak for the benefit of axle service(re grease or coated)as I have done neither. The axle failures I have seen have never been the cv joint on its own...always been another problem that led to a failure or caused the cv joint to get ruined.
Ron
RAmotorsports


#7
Posted 08-15-2017 11:24 AM

Not to pile-on (but I will), I do a bearing replacement every year and as others have noted, check for other issues after contact (mainly play in the bearing itself).
Regarding the flanges (where the studs are pressed into), inspect them thoroughly when they're removed from the upright/bearing and smooth/polish any high areas.
Said inspection also must include using a magnifying glass on the stud holes themselves to look for cracks.
I keep a spare pair of uprights with me in my track box if there ever is contact during a weekend. Automatically take it out of service when that happens and replace the bearing/check the flange.
Axles, I get mine rebuilt by Gator Axles in Florida. Had two pair done so I've also got a spare pair (again) and it was under $400 for both sets.
Granted, my $60 in 2-day shipping via FedEx wasn't cheap but they did a fantastic turnaround in terms of time and getting them back to me.
HTH!
Brandon

#8
Posted 08-16-2017 11:59 AM

Just separate them now and replace. if you damage a new one, use the spare old one to replace at the track. Once you separate it once, they fall out the rest of the time.
Don't forget new axle nuts.
-Z
#9
Posted 08-17-2017 09:24 AM

Thanks guys, sounds like my concern about separating the two for the first time at track is a valid one. I'll pick up a new set of axles to go with the uprights and rebuild the originals. So, what is better for the splnes, anti-sieze or grease?
Chris
Happiness is a dry martini and a good woman ... or a bad woman.
- George Burns
#10
Posted 08-17-2017 09:29 AM

Axles, I get mine rebuilt by Gator Axles in Florida. Had two pair done so I've also got a spare pair (again) and it was under $400 for both sets.
Granted, my $60 in 2-day shipping via FedEx wasn't cheap but they did a fantastic turnaround in terms of time and getting them back to me.
HTH!
Brandon
A little unclear, was it $400 to rebuild 2 half-shafts or 4? Also, with new units from NAPA costing $90, what's the incentive to rebuild? Are the OEs significantly better?
Chris
Happiness is a dry martini and a good woman ... or a bad woman.
- George Burns
#11
Posted 08-17-2017 09:30 AM

"new" being relative with respect to the axles as I don't think they're available anymore from Mazda. Same for the uprights. Be sure to only get NB uprights for your car as yours are 5mm (I think) wider than an NA.
Flanges & bearings are identical between NA & NB.
For the splines I just use Permatex silver-infused anti-seize. Easy peasy and as others have noted, after you do it a couple of times the axle no longer stays rusty where it contacts the flange.

#12
Posted 08-17-2017 09:46 AM

2 pairs (4x axles) - they disassemble, inspect, grease, install using new boots & straps. They told me they have a stash of parts they can use to replace any questionable bits found during the separation/cleaning so it's not like you're getting a non-compliant part back. That was my one concern: ending up with an axle that can be protested as non-compliant.
I can't comment on any NAPA or otherwise as I've never purchased any axle new, only used ones. And even then, rebuilding the one pair I did is something I'll never do again with the Gator service being that cheap.
A little unclear, was it $400 to rebuild 2 half-shafts or 4? Also, with new units from NAPA costing $90, what's the incentive to rebuild? Are the OEs significantly better?

#13
Posted 08-17-2017 03:51 PM

Cal
#14
Posted 08-19-2017 09:41 AM

2 pairs (4x axles) - they disassemble, inspect, grease, install using new boots & straps. They told me they have a stash of parts they can use to replace any questionable bits found during the separation/cleaning so it's not like you're getting a non-compliant part back. That was my one concern: ending up with an axle that can be protested as non-compliant.
I can't comment on any NAPA or otherwise as I've never purchased any axle new, only used ones. And even then, rebuilding the one pair I did is something I'll never do again with the Gator service being that cheap.
Thanks Brandon, I may look into using Gator during the off-season.
Chris
Happiness is a dry martini and a good woman ... or a bad woman.
- George Burns
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