1987-1988 DeVille & Fleetwood Tail Lamp: The Critical FWD vs. RWD Difference
This guide covers the essential compatibility check for FWD models, common failure points like water leaks, and how to choose a quality used tail lamp assembly.
- The most critical step is verifying compatibility: these parts only fit Front-Wheel Drive (FWD) DeVille and Fleetwood models, not the Rear-Wheel Drive (RWD) Brougham which uses different vertical lights.
- Water intrusion is the primary cause of failure. When buying a used lamp, inspect it carefully for any signs of cracks or past moisture inside the housing.
- Replacement is a very easy DIY job that requires basic tools and can be completed in under 30 minutes.
- Used OEM assemblies are the most common replacement option, as new parts are scarce and often only consist of the lens itself.
The Most Important Check: FWD vs. RWD Models
Warning: The single most common mistake when buying a replacement tail lamp for a 1987-1988 Cadillac is purchasing the wrong one for your car's drivetrain. The tail lamps for Front-Wheel Drive (FWD) DeVille and Fleetwood models are completely different from those on the Rear-Wheel Drive (RWD) Brougham models.
- 1987-1988 FWD DeVille & FWD Fleetwood: These models use a wide, horizontal tail lamp assembly.
- 1987-1992 RWD Brougham (previously Fleetwood Brougham): These models use a tall, vertical tail lamp assembly.
Before purchasing, you must verify that your vehicle is Front-Wheel Drive. The parts are not interchangeable. An easy way to tell is by looking at the shape of your existing tail lights; if they are long and horizontal, you have a FWD model this guide applies to.
Symptoms of a Failing Tail Lamp
Failure in these tail lamps can show up in several ways, ranging from simple bulb issues to problems with the entire housing.
- Dim or Non-Functioning Bulbs: Often the first sign of a problem. While it could just be a burnt-out bulb, it can also indicate a corroded socket or wiring issue caused by water entry.
- Condensation or Water Inside the Lens: If you see moisture, fogging, or water sloshing around inside the housing, the factory seal has failed. This will lead to chronic bulb failure and electrical shorts.
- Cracked or Hazy Lens: The plastic lens can become brittle with age and develop cracks. Sun exposure can also cause the lens to become hazy or faded, reducing light output and making your vehicle less visible.
- Rapidly Blinking Turn Signal ("Hyperflash"): On these vehicles, a fast-blinking turn signal is the car's way of telling you a bulb has burned out. If you've replaced the bulb and it still blinks fast, you may have a corroded socket that isn't making a good connection. 🎬 Watch this quick guide on diagnosing classic car tail light issues
Buying a Used 1987-1988 DeVille Tail Lamp: What to Check
Since new OEM tail lamp assemblies are largely unavailable, buying a quality used part is the most common solution. Here’s a detailed checklist for inspecting a used tail lamp before you buy:
- Check for Cracks: Carefully inspect the entire lens and housing for cracks, especially around the mounting points and corners. Even small hairline cracks can let water in.
- Look for Haze and Fading: Hold the lamp up to the light. Check for a cloudy or hazy appearance on the red lens, which is a sign of UV damage that can make the light appear dim.
- Inspect for Water Stains: Look inside the housing for any dried water lines, mineral deposits, or a green/white crust on the reflective chrome surfaces. These are clear signs the lamp has had water inside it before.
- Examine the Bulb Sockets: If possible, twist out the bulb sockets and inspect the metal contacts. Look for any signs of rust, corrosion, or melted plastic. A clean socket is a good indicator of a well-sealed lamp.
- Verify Mounting Studs: Check the back of the housing to ensure all threaded mounting studs are present and not broken off. Broken studs will make it impossible to properly secure the lamp to the vehicle.
- Confirm Part Numbers: If possible, match the part number on the used lamp to your original. Common part numbers for the right (passenger) side include 16507282 and 5974728.
Known Issues, Recalls, and Service Bulletins
A search of the National Highway Traffic Safety Administration (NHTSA) database shows no recalls or technical service bulletins (TSBs) specifically for the tail lamp assemblies on 1987-1988 Cadillac DeVille models. Most issues are related to normal aging of materials, such as seals drying out or plastic becoming brittle.
Other lighting-related recalls for this era generally pertain to different components like brake switches or unrelated systems.
Cost Comparison
Pricing for replacement tail lamps can vary significantly based on condition and source.
| Part Type | Estimated Price Range | Notes |
|---|---|---|
| New OEM (NOS) | $170 - $250+ | New Old Stock (NOS) parts are extremely rare and typically only for the lens, not the full assembly. |
| New Aftermarket | $20 - $50 | Complete assemblies are rare; this price usually reflects individual components like sockets or bulbs, not the full housing. Quality and fit may not match OEM. |
| Used OEM | $70 - $150 | This is the most common and practical option. Price depends on condition (cracks, fading, etc.). |
| Shop Labor | $50 - $100 | Replacement is straightforward and typically takes 0.5 to 1 hour of labor. |
Replacement Guide
Replacing the tail lamp assembly on a 1987-1988 DeVille is a simple DIY task.
- Difficulty: 1 out of 5
- Time: 15-30 minutes per side
- Tools Needed: Basic socket set or nut driver
The general procedure involves pulling back the trunk liner to access the nuts on the back of the tail lamp studs. Once the nuts are removed, the assembly can be carefully pulled out from the body of the car. Disconnect the wiring harness, connect it to the new lamp, and reinstall by reversing the steps.
Pro Tip: When installing a used tail lamp, it's a good idea to apply a thin bead of clear silicone sealant around the edge where the lens meets the housing to improve its water resistance. Also, replace all the bulbs at the same time to ensure longevity and brightness.
Frequently Asked Questions (FAQ)
How do I know for sure if my Cadillac is Front-Wheel Drive (FWD)?
The 1987-1988 DeVille and Fleetwood (non-Brougham) models were built on a FWD platform. The larger, more traditional-looking Brougham model from the same years was RWD. The easiest visual cue is the tail lights themselves: FWD models have wide, horizontal lights, while the RWD Brougham has tall, vertical lights.
Can I just replace the cracked lens instead of the whole assembly?
Sometimes, you can find just the lens for sale, often as a New Old Stock (NOS) part. However, separating the old lens from the housing without damaging the housing is difficult, as they are sealed together. In most cases, it is easier and more effective to replace the entire assembly.
Why are my lights dim even with new bulbs?
Dim lighting with new bulbs can be caused by a few issues. The most common are a poor ground connection for the socket, corrosion inside the socket preventing full electrical contact, or a hazy/faded lens that is blocking light output.
Are the left and right tail lamps the same?
No, the left (driver-side) and right (passenger-side) tail lamp assemblies are mirror images of each other and are not interchangeable. They will have different part numbers. For example, 16507282 is a common number for the right side.
OEM Part Numbers
These are some of the known OEM part numbers for the 1987-1988 FWD DeVille and Fleetwood tail lamp assemblies. Always try to match your existing part number when possible.
| Part Number | Description |
|---|---|
| 5974728 | Right (Passenger) Side Assembly/Lens |
| 16507282 | Right (Passenger) Side Assembly |
| 1623706 | Known OEM Number |
| 16503657 | Known OEM Number |
| 16503934 | Known OEM Number |
| 16504282 | Known OEM Number |
| 16507281 | Likely Left (Driver) Side, pair to 16507282 |
| 5974727 | Likely Left (Driver) Side, pair to 5974728 |
Helpful Videos
Technical Specifications
OEM Part Numbers: 1623706 16503657 16503934 16504282 16507281 16507282 5974727 5974728
Fits 1987-1988 Front-Wheel Drive (FWD) Cadillac DeVille and Cadillac Fleetwood models. Does not fit Rear-Wheel Drive (RWD) Brougham models.
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.
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