TECHNICAL Q&A
ANSWERS TO YOUR DIESEL QUESTIONS
I have a 1991 Dodge D250 2WD equipped with a Cummins 5.9L diesel and automatic transmission. My father bought this truck new in 1992 and I’ve sort of inherited it. Seems the 2WD trucks have a difficult time with ball joints and other front suspension components. I see half-ton 2WDS in magazines with Cummins swaps that maintain the stock suspension designed for a much lighter gasoline engine. I love this truck, but I don’t understand why the front suspension components are wearing out so quickly. Are there any aftermarket suspension component manufacturers offering better parts? Can I perform some other kind of conversion or swap to improve parts life?
Dave Wessel
Gillette, WY
The suspension components used by the firstgeneration Dodge diesel two-wheel-drive pickup trucks (produced from 1989 to 1993) were challenged by the extra weight of the 5.9L Cummins. Sagging coil springs and short balljoint life appear to be the result. Fortunately, the aftermarket has developed a range of suspension parts that can help the first-gen Dodge diesel trucks. From what research we’ve done, the brand name MOOG comes up most
often as the best fix for Dodge pickup trucks like yours. See http://www.moog-suspension-parts. com/products/dodge_w350_1992.
Federal Mogul Corporation (Federalmogul.com) manufactures its steering and suspension parts under the MOOG brand name. MOOG offers a range of heavy-duty suspension and steering replacement parts that solve problems for most Ford, Dodge and GM trucks. The coil springs you want are the MOOG Super Heavy Duty 7226S, which should solve your spring problem for a few years at least. The 7226S coil spring is rated at
1,135 lb/in. Other first-gen owners have used the 5716S coils, which are rated at 1,430 lb/in and might be a better choice for a plow truck or those running a heavy aftermarket front bumper. If we were rebuilding the front-end of your truck, we’d use all MOOG parts. The problem people are having with short parts life is often due to inferior imported parts, which don’t offer the quality or durability required by the early Dodge diesel pickups.
Once the new parts are in service, it’s critical that you develop a maintenance program
that includes frequent service for all related grease fittings, as well as installing new shock absorbers and keeping your tires balanced. Letting routine maintenance slide can create a cascade of problems affecting all the related front suspension parts. In addition, running larger-than-stock tires and/or aftermarket wheels with the wrong offset can also shorten ball-joint and steering component life.
Regarding the half-ton diesel conversions you mentioned, what you’re not hearing about is how the suspensions hold up after a few years of use. A set of ball joints designed for the weight of a factory-produced half-ton truck will wear out sooner when subjected to the extra weight of the Cummins. The question that hasn’t been answered is, “How much sooner?” For owners of most of these conversions, component life can probably be defined as being “long enough” because these trucks are not being worked hard or driven like most factory-produced 2500/3500 diesel pickups.