Dodge Ram 50 Engine Oil Pressure Switch and Sender Guide (1983-1993)
Is your oil light on or is your gauge acting strange? Here’s what you need to know before you buy a new oil pressure switch.
- If the oil light comes on but the engine sounds fine, the switch is the most likely problem, not the engine itself.
- This is an easy and inexpensive DIY repair that usually takes less than 30 minutes.
- Verify if you need a 'switch' (for a light) or a 'sender' (for a gauge) before ordering.
- For this truck, a quality aftermarket brand like Standard Ignition or Hella is a reliable and cost-effective choice.
Symptoms of a Failing Oil Pressure Switch on a Ram 50
When an oil pressure switch fails, it can be scary. It might make you think your engine is failing, but often it's just a bad sensor. Here are the most common signs that the switch itself is the problem:
- Flickering or Solid Oil Light: The red oil warning light on your dash might flicker, stay on all the time, or not come on at all when you start the truck. If the engine sounds normal and isn't making any new ticking or knocking noises, the switch is the likely culprit.
- Wrong Gauge Reading: If your truck has an oil pressure gauge, a bad sending unit can make the needle read zero, max out completely, or jump around randomly.
- Leaking Oil: A very clear sign of failure is seeing oil on the sensor itself or dripping from it. The internal seal can fail, allowing oil to leak out and sometimes into the electrical connector.
Real Low Oil Pressure vs. a Bad Sensor
If your oil light comes on AND you hear loud ticking, knocking, or grinding noises from the engine, pull over and shut off the engine immediately. This could be a real low oil pressure problem that will destroy the engine. However, if the light comes on but the engine sounds perfectly healthy, it is much more likely that you just have a bad sensor.
Choosing the Right Aftermarket Oil Pressure Switch
For a truck from this era, you don't necessarily need to hunt down an expensive original Mopar part. A quality aftermarket switch is a reliable and affordable choice. The key is to choose a brand with a good reputation for electronics. Based on the available options, here is a breakdown into tiers:
- Good Quality (Recommended): Brands like Standard Ignition (SMP) and Hella have a long-standing reputation for producing reliable electronic components that meet or exceed original quality. They are a solid choice for a dependable, long-lasting repair.
- Value Tier: Brands like Holstein and Facet often come at a lower price. Holstein promotes its parts as being made in OE-supplying factories with a low failure rate and good warranty. Facet also claims quality equal to original parts. These can be a good option if budget is the main concern.
- Store Brands / Economy: Crown Automotive is well-known for Jeep parts but offers components for many older vehicles, including the Ram 50. These parts are typically focused on being a direct, affordable replacement.
Switch vs. Sender: Know Which One You Need
Before you buy, check if your truck has an oil pressure warning light or a gauge. A "switch" is a simple on/off device for a light. A "sending unit" or "sender" is for a gauge and sends a variable signal. They look similar but are not interchangeable, so make sure you order the correct part for your dashboard setup.
Estimated Costs for Replacement
| Part Type | Estimated Cost |
|---|---|
| New Aftermarket Switch/Sender | $7.46 - $58.68 |
| New OEM (Mopar) Switch/Sender | $45 - $90 |
| Shop Labor | $50 - $100 |
Frequently Asked Questions
My oil gauge suddenly dropped to zero. Is my engine toast?
Probably not. If the engine isn't making loud knocking or ticking noises, the sudden drop is almost certainly a failed sending unit or a wiring issue. The first step is to check your oil level. If it's full, the next logical step is to replace the sender.
🎬 See how to test your oil pressure sensor with basic tools.Where is the oil pressure switch located on a 1983-1993 Ram 50?
The oil pressure switch is typically screwed into the engine block, often located near the oil filter. 🎬 Watch this video to see the sensor location and replacement. You will usually need to access it from underneath the truck. On some engine models, it might be near the distributor or power steering pump.
Can I replace the oil pressure switch myself?
Yes, this is a great DIY job for beginners. It's usually easy to access once you're under the truck. The job involves unplugging the wire, unscrewing the old switch with a wrench or a special deep socket, and screwing the new one in. The whole process should take less than 30 minutes.
🎬 Watch a quick walkthrough of the replacement using basic hand tools.Are there any recalls for the Ram 50 oil pressure switch?
No, there are no official recalls or Technical Service Bulletins (TSBs) from Dodge or the NHTSA for the engine oil pressure switch on the 1983-1993 Dodge Ram 50. Any failures are due to the age and normal wear of the part.
Helpful Videos
Technical Specifications
OEM Part Numbers: MD138994 MD138993
Typically features a 1/8" NPT thread size and a single-pin electrical connector. Varies between a simple switch for a warning light and a variable sending unit for a pressure gauge.
We Have This Part in Stock
The information in this article is provided for general reference and educational purposes only. Vehicle specifications, procedures, and part compatibility can vary by production date, trim level, and region. Always consult your vehicle's factory service manual and verify part numbers before purchasing or performing repairs. Safety-critical components such as airbags, seat belts, and braking systems should be installed by a qualified professional.
- Dodge Ram 50: