Is a valve adjustment a good idea for Jeri's Dodge Ram?

Dear Car Talk

Dear Car Talk | Mar 01, 2009

Dear Tom and Ray:

I have a 2002 Dodge Ram diesel 2500 two-wheel-drive six-speed manual with 130,000 miles. It's primarily used as a commuter truck -- with a little bit of horse and hay hauling. I love this truck and plan to drive it for years. The dealership recommended a 100,000-mile valve adjustment as routine maintenance. Although I'm meticulous about maintenance, I'm reluctant to interfere with an engine that works well. Do you recommend a valve adjustment, or is this possibly opening a can of worms? Thanks! -- Jeri

TOM: Jeri, we strongly recommend regular maintenance -- for cars AND people -- even when nothing is obviously wrong.

RAY: Right. Don't wait until you're like my brother, and EVERYTHING is obviously wrong.

TOM: This truck came with two available engines. There's a 24-valve version and a 12-valve version. The 24-valve engine has self-adjusting valves. But if you have the 12-valve, six-cylinder version, you DO need to have your valves adjusted by a mechanic.

RAY: And with 130,000 miles, you're overdue. If your valves are out of adjustment, the engine can run less efficiently, because the valves aren't opening as far as they should. That decreases your performance and fuel economy.

TOM: Unadjusted valves also shorten the life of your engine. If there's slop in the valve train, components like the camshaft and lifters will bang against one another and wear out sooner.

RAY: And the final reason to do the adjustment is that properly adjusted valves make the engine run quieter. Not that you'd notice in this truck! But you might.

TOM: Actually, you should compare the cost of the valve adjustment with a set of those Bose noise-canceling headphones. And then go for whichever one is cheaper, Jeri.

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