what are the most common problems with the 1970 oldsmobile cutlass supreme sx?

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Great question! The 1970 Oldsmobile Cutlass Supreme SX is a fantastic muscle car, but like any 55-year-old vehicle, it has some common issues to watch for:

**Top Problems to Know About:**

**Engine Issues** - The big 455 V8 is powerful but has some weak points:
- Overheating on highway drives (head gasket design issues)
- Oil starvation problems from tiny return holes in the heads
- Timing chain wear causing pinging and rough running

**Rust Problems** - Being a convertible makes this extra important:
- Rear quarter panels behind the wheels (very common)
- Trunk drop-offs and windshield header
- Lower fenders and door bottoms

**Electrical Gremlins** - Classic 1970s GM issues:
- Heater/AC fan only works on low speeds
- AC compressor cycling problems
- General wiring issues from age

**Mechanical Weak Points:**
- TH400 transmission can slip or overheat under heavy use
- Weak bottom end (2-bolt mains) can flex under the 455's torque
- Rear main seal leaks on higher mileage cars

The good news? Most of these are well-documented fixes in the Oldsmobile community, and parts are generally available. The SX is particularly cool because it was Oldsmobile's sneaky way of putting a big-block muscle car past the insurance companies!

Would you like me to help you find similar Cutlass models, or do you have questions about any specific issues?

Lot N208282: 1970 Oldsmobile Cutlass Supreme SX

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Lot N208282: 1970 Oldsmobile Cutlass Supreme SX

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