Track Junkies: What is your rear wheel bearing life ??

[BGTV8]

My car is sounding suspiciously like it is suffering bearing noise from the rear -could be rear wheel bearings, could be diff, and could even be gearbox as 6th is developing a case of the crunchies.

Before sticking it on the hoist and running it hot and wandering around the car with the engineer's stethoscope (screwdriver with plastic end to ear and steel end to hub/diff/gearbox housing), does any track junkie on the forum have any data on rear wheel bearing life ....

My car has covered 110,000 klics and done nearly 50 track days, so it has had a pretty severe spanking thus far (I already have good "life data" on front wheel bearings) and is still on original rear wheel bearings.

RB

[Rusty]

I've only got a little over 20,000 miles with about a dozen trackdays. No noise from the rear that I can hear. When I replaced the wheel studs with longer ARP studs. I checked the bearings, and all fell good.

[clintfocus]

68k on my bearings with 4 years of tracking and wide/sticky tires. i check my bearings and hubs for play and cracks before events. im curious as to when im going to need to change them as well. 370s have significantly stronger/larger bearings/hubs then 350s, so we should get a good amount of life out of them

[NORAIN]

Could it be your diff.? I hear there's a service bulletin for the diff clicking. A friend of mine is taking his in tomorrow for it.

[Mike]

24000 miles, at least 16000 track miles. no problems. I did just have to replace my transmission though.

[phunk]

Originally Posted by Mike

at least 16000 track miles.

woah! that is awesome

[synolimit]

I've seen a g37's rear bushings go out. I'd check there and for a track car I'd 100% upgrade.

https://www.splparts.com/chassis-Z34.html#SPLRKBZ34

[BGTV8]

Originally Posted by synolimit

I've seen a g37's rear bushings go out. I'd check there and for a track car I'd 100% upgrade.

https://www.splparts.com/chassis-Z34.html#SPLRKBZ34

Already replaced the diff bushes with after-market poly ..... am putting the car on the hoist this afternoon for the engineer's stethoscope treatment. Be interesting to see what I find.

I have noticed that backlash in the diff is "growing" so I may have a pinion bearing issue and/or pinion/ring gear wear.

I post the results when known this evening.

[synolimit]

Originally Posted by BGTV8

Already replaced the diff bushes with after-market poly ..... am putting the car on the hoist this afternoon for the engineer's stethoscope treatment. Be interesting to see what I find.

I have noticed that backlash in the diff is "growing" so I may have a pinion bearing issue and/or pinion/ring gear wear.

I post the results when known this evening.

Not the rear diff, the rear knuckles. Look at the link.

[BGTV8]

Originally Posted by synolimit

Not the rear diff, the rear knuckles. Look at the link.

Gotcha ... will check those as well ... tks

[travisjb]

100% good here

[BGTV8]

Finally found the problem ...

my RH rear tyre has started to delaminate under the tread - it shows up as a discernable line across the tread face where the belts overlap in the carcass itself. The circumferential belts had started to separate under the carcass/tread rubber. It was this that was making the sound when driving along and had me fooled into thinking it was a mechanical (eg: bearing) noise - once per wheel rotation.

The tyres are RS3 that are coming up for 2 years old and since we heading into winter here, they have been given a bit of a warm-up as I exit my driveway each morning for the last 4 or 5 weeks - which I can do now that I have my yaw sensor power isolation switch installed - have been in the habit if lighting them up each morning as they were not worth a pinch of goats-cr4p from a grip perspective otherwise. They were still OK if I could get heat into them, but diabolical when cold.

However, seeing the line across the face of the tyre, they had to go !!

Both rears now replaced with Direzza DZ II.

Oh well .....