Honest, Guys...I've researched this question here on the site and on buickperformanceclub.com/springs.htm, and feel I have conflicting information. I'm replacing the front coil springs on my 1971 GS 350 with A/C (convertible body style) and want a bone stock ride height and ride. The Moog catalog clearly specs a 5536 front coil spring for this GS application. It is not showing this number as "heavy duty"....simply the correct OEM replacement spring for the GS front. However, the buickperformanceclub page indicates a Moog 5398 is a good spring number for the front of the GS. The Moog catalog shows the 5398 as the correct front spring for the Skylark, but not the GS. Also, the 5536 uses a larger diameter wire in spring construction than does the 5398, so they probably aren't "close" in ride. Could someone please offer their experience on the the Moog 5536 front spring vs. the 5398 front spring? Also, does the front coil spring in my application use a rubber insulator at the top? I know the rear coil spring does, but I haven't had the car up in the air yet, to check on the front. Thanks for any help, Gang. John
I just installed the 5398 on my 70 350 sedan, no modification to the springs. perfect height and smooth ride.
