within spec
August 28th, 2006I went with a friend of mine to pick up his car after alignment the other day, and as I reviewed the alignment printout eyed the ‘thrust angle’ specification first – it was not at 0 or .01, not at .02. it read .03, far greater than I find acceptable for my own cars. (Thrust angle is the angle at which the car is going down the road – the greater the thrust angle the farther to one side the rear tires are in relation to the front).
So I looked at the rest of the specs – it was the toe at the rear that bothered me; there wasn’t symmetry – one rear wheel was toed in 50% more than the other.
We questioned the tech on why that wasn’t brought in closer and were told, “I hate to give you the Dobbs answer but it is within specification.”
That phrase is a red flag, a term as meaningless as Montana’s speed limit being set at whatever was ‘reasonable and prudent.’
There is a huge difference between being in spec and being right. If the caster should be between 4 and 6 degrees, 5 is the unspoken ideal. Having one near 6 and the other near 4 is ‘within spec’ and yet your car will steer itself into the ditch. Given that engineers come up with ingenious ways to either actively or passively steer the rear wheels (or avoid letting the wheels steer) by fractions of a degree, every tenth counts.
So what do I look for in an alignment? It seems like I’m stating the obvious but I look for symmetry. Ideally I want each setting dead in the middle of the range but more importantly I want them the same from side to side. And if the alignment shop isn’t willing to do that I either make them do it again or go elsewhere.
You can’t expect things to be done right but you can demand that they are.