C5/C6/C7 Wheel bearings

[mfain]

Here is something that may interest some of you (if you like saving money). Those running C5/C6 front uprights and bearings know that the base and Z06 hubs are not as strong as the ZR1 hubs with their larger bearings and thicker wheel mounting flanges. But the ZR1 hubs are pricey - $350+. I just bought a C7 hub assembly (GM 20981829) to measure. It does not have the wheel speed sensor or the splined center (front wheel only), but a splined rear hub assembly is available. the GM list price is $169.64, but it is listed cheaper at places like Rock Auto. The AC Delco number is FW412. The good news is that the bearing has the same bolt pattern and inside and outside registers as the C5/C6, so it fits a C5/C6 upright, AND it has the same wheel mounting flange thickness as the ZR1 and the outer diameter of the casting at the bearing is the same as the ZR1, which is .5 inch larger than the standard C6. My conclusion is that it uses the same large bearing as the ZR1 hub. I've included a couple of pictures showing the C7 hub assembly in a ZR1 (C6) upright, a C6 Z06 hub, and a ZR1 hub in an ATS spindle (designed to use C6 bearings).

 

[phantomjock]

PAPPY! My Hero!:thankyou:
Touchdown - on Superbowl Sunday!
I've been crawling all over the InterWeb for this -- and it was here all along.
My entry was through PT - of all places.

Now if I could only find/get the loads (thrust bearing) data!

Thanks, and

Cheers - Jim

May your favorite team win -as long as its the Patriots! :beer:

 

[phantomjock]

Confirmed!

I just got off the phone with Dan @ Van Steel. He confirmed for me that GM was so impressed with the SKF Racing Bearings, they went with SKF from 2010 onward.

So, Pappy's observation and analysis was spot-on. If you buy the AC Delco FW412 - it is the equivalent of the Racing Bearing!

Yippie!!

Thanks Pappy! Thanks GM!

Cheers - Jim

 

[69427]

Do I infer correctly that these bearings won't work for those of us with antique C4 suspensions?

 

[phantomjock]

Do I infer correctly that these bearings won't work for those of us with antique C4 suspensions?

These are the 3 bearing mount - not the 4 as in theC4. I was hoping that there were some C4 uprights that would fit - but they look to be too small even to modify.
I did a lot of looking (research) to find drop spindles for my mod:


But, Rock Auto has a great price on these:

And you can use the dimensions to confirm C4 fit/or no.

These are less than a hundred bucks shipped from GM Parts Direct:

Suggest price compare both. Rock Auto is shipping free until the end of the month I recall.

Good hunting - Cheers Jim

PS I can dimension the C7 if you want/need/like.

 

[vette427sbc]

Anyone happen to have the dimensions for a C4 rear hub/bearing? Would be interesting to see if the C5/6/7 was dimensionally the same, or at least close...

 

[BBShark]

I think I have some late C4 rear hubs around. What dimensions are you looking for?

 

[vette427sbc]

I think I have some late C4 rear hubs around. What dimensions are you looking for?

Essentially the same ones as in the C5/6/7 drawing (depth and bolt circle being most important)... Im trying to see if I can swap this bearing in my C4 knuckle/bearing support without changing the CNC'd caliper bracket that I already had made. I know the C4 hub and half shafts are the weak link in my rear suspension. Just trying to pre-plan for a 33 spline ('09+ C6 hubs) CV axle and upper link conversion in the future. My car is still in NH, otherwise Id measure my existing hubs.
Thanks!

 

[BBShark]

This is what I measured (GM Hubs from a late 90's car). The 3 bolt flange was a little difficult to measure but it looks like it is 4.75" BC. The other difference is the pilot is stepped so there are two diameters.

 

[vette427sbc]

Much appreciated! Looks like I’ll be designing a new caliper bracket for next year...