In a message dated 11/05/2001 10:48:28 PM Eastern Standard Time, tobyp@xxxx writes: << After I explained where the bolt was installed, and what it did, the lab technician asked me a very simple question ... "Why did they use such a crappy bolt for this critical function?" Good question. >> The chassis is really disappointing. Especially when compounded with rust issues, frame distortion, epoxy problems, and the inauspicious trailing arm bolts. The December 1981 Motor Trend Magazine article has a separate analysis of the chassis technical limitations and impressions of the DeLorean steel backbone. The poor engine placement in the backbone, flexing of a brittle chassis, old age, stress from cornering, bumps in the roadways, heat from exhaust, the engine weight is far too much load & stress for the rear suspension, especially the radius arm bolts. "...because the engine is too wide to fit into the aft V, it is mounted behind the axle, with the transmission positioned ahead of the axle. The engine location gives the car its most undesirable characteristics: a high rear-bias weight distribution (35/65), and a very high polar moment of inertia." The DMC engineer's idea was to incorporate larger tires in the rear than the front to help stabilize the car. "One other engineering problem with the DeLorean is the rear axle locating system. The Trailing links angle toward the centerline of the chassis and allow the wheels to change toe-in (or toe-out) as a function of body roll. This causes the rear wheels to steer their end of the car during the transition from straight line to cornering, a handling trait that is something less than endearing." So, those tiny little radius arm bolts actually serve a multitude of functions. One tiny hairline crack in one of those bolts, along with the right bump in the road and it's time to call your insurance agent.