Recently, I noticed my steering wheel "off-center" when driving straight, and the car drifting to the left slightly, hence I took it to the dealer to check the alignment. The steering wheel issue was corrected, however on the customer invoice sheet it stated "Castor is maxed out. Gave best split." On the accompanying 4-wheel Total Alignment page that shows the before and after Camber, Castor, Toe values, the front left Castor (after) read 8.8 deg, the right read 9.3, noting that the spec is 7.4 +/- .6. We know that the car will, and does, pull in the direction of the less positive Castor. Question. My last alignment check 5 months ago had no issues w/ the Castor, I have not Auto-X'ed or hit anything significant what would make me think I caused this newly wacked Castor. I'm half way thru my warranty period, what are my chances of fighting to get this castor situation covered? How could the Castor be "maxed out." First time writer, sure appreciate this Forum and any suggestions from anyone who could help me out. Thanks

 

Welcome! Unfortunately alignment isn't covered by your warranty other than GM will provide one freebie in the first 5k miles since a lot of us had mis-aligned cars from the factory. In my experience trying to get my alignment where I wanted it on my Z06 every tech who touches it will get a different result so you could complain to them and have them try again asking for a different tech, in some cases it depends on what wheel they start on as to what they will have issues with. I ended up finding a shop that does a ton of work for weekend SCCA guys/gals and also does a lot of Viper and Vette alignments to do mine. It took him an hour to get it perfect exactly where I wanted it and only cost $150 (half what the dealer wanted). I would check your local Vette club to see who others are using before paying a dealer to mess with it again. If they'll re-do it for free than it's worth a shot I guess though.

If you are paying for an alignment make sure they have the tools to check and adjust the REAR caster as well. The typical hunter alignment machine won't check/adjust that, they need a separate pair of tools from GM. Most SAs at the dealer have no idea the rear caster is adjustable on the C7 and it being out of whack can be a bad deal too, especially if one side is positive and the other negative (still in GM's specs by the way). Most cars don't have a rear caster adjustment.

 

This isn't a problem that requires a repair on the car. It depends on what the mechanic did to adjust caster. Can you post your alignment sheet showing both before and after settings? What did you tell them you wanted when you took it in for the alignment? Caster and Camber adjustments affect each other and they both affect toe settings. Toe settings by themselves don't affect caster or camber.

It sort of looks like the mechanic did a rush job without doing a great job so the result was sloppy. There is a lot of adjustability in the front. The mechanic can change shims behind the UCAs and change the cams on the LCA mounting bolts. Adding shims behind the front UCA dog bones will increase positive camber while reducing negative camber. Turning the front mounting LCA mounting bolt cam so the LCA is pulled forward will add positive caster while reducing negative camber and turning the rear LCA cam the so the LCA is pushed forward increases positive caster while increasing negative camber.

Bill