chrysler 300 problems

Sat down with a buddy of mine last month who runs a transmission shop east of Mesquite. He’s been in the business 35 years. I asked him what was the worst engine he ever saw come through his bay. Didn’t even pause. “2.7 Chrysler. Hands down. I’ve pulled more of those out of Sebrings than I’ve eaten breakfasts.”

That’s about right.

The 2.7L V6 that Chrysler dropped into the Sebring, Concorde, Intrepid, 300M, Stratus, and a fair number of LH-platform sedans from 1998 through about 2010 is one of the worst-engineered mass-produced engines in modern American history. It’s not even close. The Theta II argument I’ll save for another day, but the 2.7L Chrysler at least has the dignity of failing in only one specific spectacular way: oil sludge that turns the bottom end into a paperweight.

What’s actually wrong

The engine has two oil drainback passages from the heads to the pan. Just two. And they’re tiny. On most overhead-cam V6s you’ll find four to six, sized properly. The 2.7L’s are undersized to the point where any contamination, any thickening of the oil, any extended drain interval at all causes the drainback to plug up. Once it plugs, oil pools up in the heads instead of returning to the pan. The pickup tube starves. The bottom end runs dry on whatever oil it can scavenge.

The engine doesn’t fail right away. It runs poorly for a while, ticks, throws codes, eats a cam chain guide. Then somewhere around 80,000 to 130,000 miles the bottom end gives up. Crankshaft journals score, rod bearings spin, and the engine locks up. By that point you’ve usually got metallic shavings throughout the entire oil system.

The kicker: Chrysler’s recommended oil change interval was 7,500 miles. On an engine that couldn’t tolerate 5,000.

What you’ll see and hear

• Oil pressure light at idle, especially when warm
• Rattle on cold start that lasts more than a couple seconds (timing chain guide chewing itself up)
• Codes for cam position correlation (P0016, P0017, etc.)
• Oil consumption rising over time
• Sweet smell of coolant in the oil if the head gaskets give up too (related but separate failure)
• Eventually, knock from the bottom end and a no-start

If you pull the valve cover and see what looks like brown peanut butter packed into the head, you’ve got terminal sludge. There’s no chemical that fixes that. The engine has to come apart.

What it costs to set right

Reality on a 2.7L Chrysler:

• Used engine from a salvage yard: $800–1,400 for the long block. You’re rolling the dice that it isn’t sludged too. Ain’t a great roll.
• Reman: Almost nobody reasonably reputable rebuilds these anymore. Prices when available run $3,500–5,000. The economics rarely work on a $4,000 car.
• Sludge cleanup attempt: Some folks try short-interval oil flushes with Auto-RX or Mobil 1 short fills to dissolve the sludge progressively. On a borderline engine that hasn’t yet locked up, this can extend life. On one that’s already knocking, it’s burying money.
• Walk away: Most owners reach this conclusion eventually. A running 2005 300M with the 2.7L is worth maybe $1,500–2,500 in good shape. Once the engine goes, the parts car value is $300–500.

Should you buy one?

No. Not at any price. The 2.7L Chrysler is one of two engines I tell folks to walk on without qualification (the Theta II GDI is the other). If you’re shopping a Sebring, Concorde, Intrepid, 300M, or Stratus from this era, look at the engine code on the option sticker or VIN before you even test drive. If it’s the 2.7L, walk. The 3.5L and 3.2L variants of the same platform are imperfect but live-able. The 2.7L is unfixable.

If you already own one and the engine still runs:

• Change oil every 3,000 miles, no exceptions, full synthetic
• Run a high-detergent oil (Mobil 1 EP works well)
• Watch the pressure gauge or warning light like your life depends on it
• Don’t drive aggressively, don’t tow, don’t load the engine
• Plan for the eventual failure and have an exit strategy

If yours has already failed: get it to a junkyard, get whatever they’ll pay, and put the money toward a different vehicle. The math on rebuilding a 2.7L is something I’ve never seen pencil out.

Why I’m still mad about this engine

Chrysler knew. They knew by 2000 that the drainback design was undersized. They knew by 2003 that the sludge complaints were piling up. They didn’t fix it. They kept building the engine through 2010 and put it in cars they sold for ten more years, knowing every one of them was rolling toward a bottom-end failure on a clock the owner couldn’t see.

The class action settlement covered some of these. Most owners never knew about it. The settlement is closed now anyway. If you’re holding the bag on a sludged 2.7L today, there’s no recourse, no warranty extension, no goodwill repair. You’re on your own.

Walk on these. Tell your buddy who’s shopping a cheap Sebring to walk too. Some engines you can rehab. The 2.7L Chrysler ain’t one of ‘em.