My 89 SSE 3800 had over 300,000 km (divide by 1.6 for miles) and only problem was noisey lifters and a harmonic balancer. My 95 SSEi has 150,000 miles and only thing so far was the harmonic balancer again. Your 98 SSE 3800 should outlast that great looking black paint job you put on her! PS. I live about 20 mins from a plant in Ontario Canada that once produced the 3800 series engines. I think they now make the big V8 blocks for the caddy and vette as well as some truck lines. The guys at the plant were really proud of the quality and workmanship of that 3800 engine.
2000 SSEi Arctic White, custom tips, FWI, 3.4 pulley, 180 stat, Intense PCM, K&N filter, solid motor mount, cleared corners and tails, silverstars, painted grilles, XM Radio.
1994 SSEi Gold, completely stock, 252K, love them AL7'*.
2006 G6 GTP Coupe....stock cause the wife said so!