1987 GMC R1500 Door Lock Kit and Cylinder Replacement
Don't let a worn-out lock compromise the security of your classic GMC R1500.
- Before buying parts, check for a sagging door by lifting it; worn hinge pins often mimic lock problems.
- Aftermarket kits from brands like Standard Ignition are the industry standard for this repair, as new OEM parts are unavailable.
- Decide if you want one key for everything; if so, buy a complete kit with a matching ignition cylinder.
- For power lock issues, inspect the wiring in the door jamb boot for breaks before replacing any components.
Signs of a Failing Door Lock
On a classic truck like the 1987 R1500, door lock problems are common and almost always due to age and mechanical wear. The symptoms are usually easy to spot and diagnose.
- Key is Difficult to Insert or Turn: The most common symptom. Years of use wear down the tumblers inside the lock cylinder, causing a poor fit with the key. You might find yourself jiggling the key to get it to work.
- Key Spins Freely: If the key turns 360 degrees without locking or unlocking the door, the small arm on the back of the lock cylinder has likely broken off or the internal connecting rod has become disconnected.
- Lock Knob is Stuck: Old grease and dirt can harden inside the door's latch mechanism, causing the interior lock knob to become stiff or completely stuck.
- Power Locks Don't Work (or only work one way): For trucks equipped with power locks, a common failure is broken wires inside the rubber boot between the door and the cab. This can cause the locks to not work at all, or only lock but not unlock. A faulty relay can also cause this issue.
Check Your Door Hinges First!
Before you blame the lock, check for a sagging door. Worn-out door hinge pins are extremely common on these trucks. A sagging door causes the latch to misalign with the striker on the door jamb, making it very difficult to close and lock. Open your door slightly and try to lift it up and down. If there is significant play, you need to replace the hinge pins and bushings. This may solve your locking problem entirely.
Choosing the Right Aftermarket Door Lock Kit
Original Equipment (OEM) door lock parts from GM for a 1987 model are virtually impossible to find new. The aftermarket is your primary and most reliable source for these parts. Fortunately, the quality is generally very good for this simple mechanical system.
Standard Ignition (Standard Motor Products): This is a well-regarded brand in the aftermarket that produces high-quality replacement parts that meet or exceed original specifications. Their kits are a dependable choice for a direct-fit replacement. Reviews from owners are generally positive, citing good fit and function.
When buying a kit, you have a few options:
- Door Locks Only: A basic kit will include two door lock cylinders and a set of matching keys.
- Complete Matched Sets: For convenience, you can buy a complete set that includes the two door locks and a matching ignition lock cylinder, all keyed alike. This allows one key to operate the doors and start the truck, just like it did from the factory. Some owners express frustration when they buy a basic kit and have to carry separate keys for the door and ignition.
Pro Tip: Service the Internals
While you have the door panel off to replace the lock cylinder, it's the perfect time to clean and lubricate the entire latch mechanism and all connecting rods with white lithium grease. Also, inspect the small plastic clips that hold the rods in place; they become brittle with age and are inexpensive to replace.
Cost of Replacing a 1987 GMC R1500 Door Lock Kit
The cost is very reasonable, especially if you perform the labor yourself. The job is well within the capabilities of a DIY mechanic.
| Part Type | Price Range |
|---|---|
| New Aftermarket (Standard Ignition) | $28.19 - $59.85 |
| New OEM | Not Available |
| Used OEM | $20 - $50 (from salvage) |
| Shop Labor | $100 - $200 |
Frequently Asked Questions
Will the new keys match my ignition?
Only if you purchase a complete kit that includes a new ignition cylinder that is keyed to match the new door locks. Standard door-only kits will come with their own keys, meaning you will have a separate key for your doors and your ignition.
Is this a difficult job to do myself?
No, this is a great DIY project for beginners. It requires basic hand tools to remove the door panel and one retaining clip that holds the lock cylinder in place. The entire process for one door can usually be completed in under an hour.
Do I need to replace the entire door latch assembly?
Usually, no. The most common point of failure is the lock cylinder itself. The internal door latch is more robust. If the latch is sticky, it can often be fixed by cleaning and lubricating it while you have the door panel off.
My power locks aren't working. Will this kit fix it?
This kit fixes the mechanical key part of the lock. If your power locks are failing, the problem is likely electrical. The most common cause is broken wires in the rubber boot between the door and the body. You should inspect that wiring first before replacing parts like actuators or relays.
Technical Specifications
Kit typically includes two door lock cylinders, gaskets, retaining clips, and a pair of keys. Complete kits also include a matching ignition cylinder.
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.
- GMC R1500: