Turbo Diesel Registry
Issue link: http://read.uberflip.com/i/637674
16 www.turbodieselregister.com TDR 91 MEMBER 2 MEMBER . . . . Continued BALL JOINT REPLACEMENT by Doug Leno After installing the steering system upgrade I just described, I visited a local alignment shop to check the toe-in specifications. Unfortunately, the shop refused to align my truck on account of a loose ball joint. I have known high volume tire stores to do this sort of thing to boost sales, but this diagnosis was no surprise, and it came from a shop that I trusted: After 150,000 miles, I knew it was ball joint replacement time. After 150,000 miles, I knew it was ball joint replacement time. My analytical nature kicked in, and I decided to do some research before choosing my parts. I rounded up four different sets of ball joints for comparison against the factory parts available from my local dealer: NAPA Chassis, Moog Problem Solver (obtained from O'Reilly auto parts), Duralast (obtained from AutoZone), and Carli Suspension. The assortment is shown in figure 1. Figure 1: from left to right: Upper ball joints from Carli Suspension, Moog, Napa, Duralast, and Mopar. Some are smooth, some are knurled, some have a grease zerk, and some are sealed. The zerk on the NAPA spart in this photograph has not yet been installed. Two characteristics were immediately apparent. First, note that the ball joints from Carli Suspension, Moog, and NAPA are outfitted with a grease zerk, while those from Duralast and Mopar are not. Secondly note that some parts are knurled, while others are smooth. In a surprising twist, I found that the two Moog parts supplied by my local O'Reilly Auto Parts store had different body textures: The upper ball joint (shown in figure 1) was smooth while the lower ball joint (see figure 2) was knurled. Both were supplied in identical boxes labeled "Moog Problem Solver." Figure 2: Lower ball joints from Moog (left) and Mopar (right). The Moog "problem solver" part supplied by my local O'Reilly Auto Parts store has a knurled body. Using a micrometer, I was able to compare the body diameters of the aftermarket parts to the factory parts, with some interesting results (see Table 1). LOWER BALL JOINTS Size compared to Mopar (thousandths of an inch) Body Surface Mopar Smooth Carli Suspension +.5 Smooth NAPA Chassis +5 Knurled Moog Problem Solver +3 Knurled Duralast ( Autozone ) +1 Smooth LOWER BALL JOINTS Size compared to Mopar (thousandths of an inch) Body Surface Mopar Smooth Carli Suspension +.5 Smooth NAPA Chassis +5.5 Knurled Moog Problem solver +3 Smooth Duralast ( Autozone ) +9 Smooth Table 1: micrometer measurements of four aftermarket ball joints compared to the factory-supplied part. As you can see, the Carli Suspension ball joints were the only ones in my test group matching factory specifications, in both body size and surface type. The locally available parts from O'Reilly, Autozone, and NAPA all measured a few thousandths of an inch larger than the factory parts. The NAPA and Moog parts combine an oversize body with a knurled surface.