I purchased my 1998 Bonneville SE in 2004 with 76,000 on it, now it has over 143,000. Being that it was sitting on a Chicago used car lot for I don't know how long, I didn't know if it was a good deal or not buying through Ebay. After I got it, I have several things done to it. It's still a good over all great car. In 2011 I had the anti-freeze problem fix with gaskets replaced, upper plenum (Upper air intake) replaced, water pump, radiator, spark plugs, wires, all hoses, all sensors, and starter replaced. Even though nothing was wrong, I still wanted to be safe than sorry. The new radiator sprung a leak and I fixed that with Bar's Leak. I also replaced the stock muffler with a Flowmaster.
I did replace the stock air box with a Secret Weapon-R intake. It comes with a washable filter and sounds great with a heavy foot. Replaced all the tires to Sumic GT 60's, 225/60R16's. Still have the Walmart battery I put in, that was in 2004.
Make sure you check your rear brakes because they do freeze up if dirty.
I still plan on keeping my Bonneville for several more years. It's fun to drive !
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