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So as a C7 owner that tracks their car frequently and looking to possibly upgrade to a C8 Z06 when it comes out, I'm just curious if the rear caster on the C8 is adjustable like it is on the C7?
I see a lot of useful links here. Thanks everyone, I'll be sure to check your options. It's not what you originally asked for, but don't forget the helper tools. I often work with both large and small parts, and due to an old finger injury, I prefer to play it safe while working. I buy a lot of useful parts from sandfieldengineering.com, I like the wide range of clamps. It was useful to me, maybe my advice will be useful to someone else here.
Last edited by Darcibeasts; Mar 14, 2022 at 07:13 AM.
A more economical rear-caster measurement solution is as follows:
1) Buy two 0.4330" size "go" gauge pins, part #23055A002 at https://www.mcmaster.com/catalog/126/2427. These are an exact fit for the machined holes in the C8’s rear uprights/knuckles. $4.08 each
2) Buy one nickel-coated low-carbon steel bar, 1” x .125” x 6” at https://www.mcmaster.com/catalog/126/3920, see: 8131K35. $11.55 each (non-nickel plated cost less if preferred)
3) Buy a Wilex angle gauge (0.1 degree accuracy), see:
A more economical rear-caster measurement solution is as follows:
1) Buy two 0.4330" size "go" gauge pins, part #23055A002 at https://www.mcmaster.com/catalog/126/2427. These are an exact fit for the machined holes in the C8’s rear uprights/knuckles. $4.08 each
2) Buy one nickel-coated low-carbon steel bar, 1” x .125” x 6” at https://www.mcmaster.com/catalog/126/3920, see: 8131K35. $11.55 each (non-nickel plated cost less if preferred)
4) Install rubber bands to hold tool steel bar on the pins (it isn't necessary to tap rubber band holding-screws)
These pictures were taken after the removal of the rear brake cooling ducts.
So I ordered the 0.433 GO pins and found that they fit very nicely on the driver side rear knuckle but are too large for the passenger side rear knuckle. I thought perhaps the holes were dirty with grime, so I tried cleaning them with rubbing alcohol and cotton swabs. Still no go on that side of the car. The only thing I can think of is that the tooling that bores those precision holes is slightly worn and is making an undersized hole on that side. I plan on ordering smaller pins, but I'm curious if anyone else has had this issue. My car is a 2022.
A more economical rear-caster measurement solution is as follows:
1) Buy two 0.4330" size "go" gauge pins, part #23055A002 at https://www.mcmaster.com/catalog/126/2427. These are an exact fit for the machined holes in the C8’s rear uprights/knuckles. $4.08 each
2) Buy one nickel-coated low-carbon steel bar, 1” x .125” x 6” at https://www.mcmaster.com/catalog/126/3920, see: 8131K35. $11.55 each (non-nickel plated cost less if preferred)
4) Install rubber bands to hold tool steel bar on the pins (it isn't necessary to tap rubber band holding-screws)
These pictures were taken after the removal of the rear brake cooling ducts.
Originally Posted by BobD59
So I ordered the 0.433 GO pins and found that they fit very nicely on the driver side rear knuckle but are too large for the passenger side rear knuckle. I thought perhaps the holes were dirty with grime, so I tried cleaning them with rubbing alcohol and cotton swabs. Still no go on that side of the car. The only thing I can think of is that the tooling that bores those precision holes is slightly worn and is making an undersized hole on that side. I plan on ordering smaller pins, but I'm curious if anyone else has had this issue. My car is a 2022.
I was going to order the pins also, until I read your comment.
Checked the part number in the pic above and it's the passenger side steering knuckle. Same for all years 2020-2024. Driver side ends with a 69.
SO, how did COPJSD get those pins in the passenger side?
I assume the driver side is good but the passenger side is too small? I wonder what size the pins are on the GM recommended tool.
Driver’s side was “ok” meaning could only get both pins in just enough to make a measurement. Passenger side was worse. I attempted to polish the pins with emery cloth but they are hardened and it didn’t make a difference.
When I read this thread last week I ordered the pins for the K/M gauge which I had from my C7 days. I haven't received them yet so I can't say what size they are (not sure I have a caliper that reads to four places either ). If I can get a measurement after they arrive I will post here. One caution for others that want the K/M pins there is a big difference in pricing between suppliers. These guys have them listed for $16.95, https://www.autotoolworld.com/Kent-M..._p_294158.html . There were two others that were $40 and over $90 .
I guess these pilot holes are another "wonder why" from GM with the differences.
OK guys, I got the proper pins for the Kent/More bracket today and they are .425 in dia.
The C7 pins were .435 for comparison. The link I listed above was where I purchased them and they were as stated $16.95 plus shipping The shipping was around $14.00 so I got two sets to make sure given the low price they included two in a pack (shipping was the same either way). Anyone want the extra set let me know, I will send for $20 total and save you half the shipping. Hope this helps.
C8 Rear Caster Adjustable?
). If I can get a measurement after they arrive I will post here. One caution for others that want the K/M pins there is a big difference in pricing between suppliers. These guys have them listed for $16.95, https://www.autotoolworld.com/Kent-M..._p_294158.html . There were two others that were $40 and over $90 
.