ML///

What's the cost for the wheel bearings? Same price for all four?

orthojoe

All 4 bearings are the same part. About $140 each

okie981

Sounds like an opportunity for some aftermarket parts. Wonder if anyone is offering upgraded replacement wheel bearings?

orthojoe

Turns out the bearing parts are the same as the gt3, which have been solid for me. Maybe I got a bad batch or hit something harder than I thought. That being said, I've haven't been off track yet in the gt4, but I have been off track multiple time in the gt3 though....

DC640

You may be right joe on possible bad batch. Plus you aren't really using sticky tires (Hoosier for example) that puts extra stress on parts. It's mainly heat and load that kills those bearings - having said that, it is odd and surprising all 4 corners are bad all at once!! Is it a significant wobbling on the hub ?

orthojoe

Yup. Re71r and cup2 only. One of the front hubs is pretty bad wobble. The rest are subtle but definitely need to be replaced for track use.

TrackDays247.com

Yeah, heat is the killer - hub temps are incredibly hot...take an on-track laser measure...you will be stunned

okie981

Thinking about this some more after reading Joe's earlier posts about the bearing failures and how his GT3 took way more track days with no bearing issues, could there be something about Joe's GT4 that cause higher hub temps compared to his GT3 for the same track use? Maybe air flow to the rotors is different? Different size wheel's and/or tires? Seems like higher temps would be more likely than all 4 bearings having some type of sub-standard manufacturing quality.

bluvan

8500 miles 9 track days at beginner pace. Front left bearing was reported showing first sign of wear with minimal movement by indie shop doing a pca tech inspection. I was kinda hoping it was a fluke and definitely hoping it was warranty, now all hopes are dashed...

vantage

Hi Joe,
What is this meter in front of your GT3 tach?

At first I thought it was a shift light, but that doesn't seem to be the case. Is it g correlated?

orthojoe

So it turns out the front bearings were fine. Just a loose lower control arm bolt which caused the play. The rears bearings did have to be replaced.

Good eyes!
It is G correlated.

I've been asked to test this device:
https://www.apextrackcoach.com/

I'll do a write up on it after I spend some more time with it and let you guys know. Talk to Clark at Apex performance if you want more details for now. It's a cool device.

Alan C.

I've read about this. Looks interesting

vantage

Thanks Joe. Ah the friction circle. I hit max g under braking and just before I start unwinding the steering, but not so much in between!

Mech33

Wow there is some serious marking BS going on on that website, and ubiquitous use of the "machine learning" buzz word.

Basically the device is just keeping track of how much total acceleration vector your car is capable of and then shows you how close you're getting to it at each instant on the track.

Fun concept, but is it actually useful, Joe? You should be able to feel the same thing, and if I couldn't feel it, I don't think I'd trust this little device's "machine learning" predictions no matter how many black and white engineering drawings they copy and paste on their website graphics.

orthojoe

Spoken like a true engineer! Lol! From what I gather, it looks like a live Gsum meter just like I use in my videos. Useful tool, but not everyone knows how to use math channels in rs2. Anyways, I'll do a more in depth write up after I spend some more time with it on Sunday. There are some cool things about it. You're welcome to try it out as well. We'll see who can log the highest 'score'.