Really? My manifolds have 21 years and 295,000 miles on them. Frankly I would be scared to mess with them. Cant imagine what a job it would be to replace them. However 2000 dollars is downright stupid.
http://www.autozone.com/autozone/pa...itu34Z9l3aa?itemIdentifier=439590_77295_5216_ So the manifolds are 225 dollars for the set. So labor is 1775$? Yeah right.
Of all the problems these trucks have, manifolds are on about page 7. Yes they may not flow the best, but upgraded headers are a rare and expensive item. Now the factory Y-pipe is a poor design, however, the best upgrade is not a better y-pipe, but a turbo, which does away with the y-pipe all together. A better muffler or a straight pipe will also improve the exhaust flow greatly.
Are you sure this guy didnt mistake your truck for a Jeep Grand Cherokee? The 4 Liter is famous for cracking the manifold