Universal Joint Replacement Guide for the 1979-1987 GMC K1500
Address clunks and vibrations by choosing the right aftermarket U-joint for your classic GMC truck.
- A clunking sound when shifting or a vibration at highway speeds are the most common signs of a failing U-joint.
- Do not delay replacement; a complete failure can cause the driveshaft to fall, leading to loss of control and expensive damage.
- Dana Spicer is the most recommended brand for durability, with their non-greasable joints often considered stronger than greasable versions.
- Confirm the exact size of your U-joints before ordering, as multiple sizes were used during this generation.
Symptoms of a Failing Universal Joint
A worn-out U-joint will give you clear warning signs. Ignoring them can lead to a driveshaft separating from the truck, which can cause major damage and a loss of control. Be aware of these common symptoms:
- Clunking Noise: A loud "clunk" or ringing sound when you shift into Drive or Reverse is a classic sign of a bad U-joint. This is caused by excessive play in the joint.
- Vibration: You might feel a vibration throughout the truck, especially as you speed up. This happens when the worn U-joint throws the driveshaft out of balance.
- Squeaking or Chirping: A rhythmic squeaking that changes with your speed often points to a U-joint that has lost its grease and is now running dry. This sound is usually most noticeable at low speeds of 5-10 mph. 🎬 Watch: How to check for play in your universal joints.
Driveshaft Failure is a Critical Risk
If a U-joint fails completely, the driveshaft can drop while you are driving. This can cause you to lose control of the vehicle, damage the transmission and other underbody components, and leave you stranded. It is critical to replace a failing U-joint as soon as symptoms appear.
Choosing the Right Aftermarket U-Joint
For a vehicle from this era, original equipment (OEM) parts are generally unavailable. The aftermarket offers a wide range of quality replacements. The main choice you'll make is between a greasable (serviceable) and a non-greasable (sealed) U-joint.
- Greasable U-Joints: These have a zerk fitting that allows you to add fresh grease periodically. This can extend their life, especially if you drive in wet or dirty conditions, but you must perform the maintenance.
- Non-Greasable U-Joints: These are sealed from the factory, just like most original parts. Many mechanics and experienced owners prefer them because they are stronger (the cross isn't drilled for a grease channel) and require no maintenance.
Aftermarket Brand Tiers for Your K1500
Based on owner feedback and mechanic consensus, aftermarket brands for your truck generally fall into these tiers:
| Tier | Brands | Assessment |
|---|---|---|
| Premium / Heavy-Duty | Dana Spicer, Moog | Dana Spicer is widely considered the gold standard and original equipment supplier for many drivelines. They are praised for strength and durability, especially their non-greasable versions. Moog is also a well-regarded premium brand, often with problem-solver designs, though some users have noted a decline in quality recently. |
| Quality Standard | SKF, GMB | SKF and GMB are solid mid-tier choices that offer good quality and value. They are reliable replacements for daily driving and standard use. |
| Performance / Off-Road | Yukon Gear | Yukon Gear specializes in drivetrain components for performance and off-road applications. Their parts are built to handle higher stress and are a good option if you have a modified truck or use it for heavy-duty work. |
Pro Tip: Replace in Pairs
It's a good practice to replace the U-joints at both ends of a driveshaft at the same time. If one has failed due to age and mileage, the other is likely not far behind. This saves you from having to do the same job twice.
Frequently Asked Questions (FAQ)
How many U-joints does my 1979-1987 K1500 have?
A typical 4WD K1500 from this period has multiple U-joints. You will find two on the rear driveshaft and three on the front driveshaft (one of which is part of a double-Cardan joint at the transfer case). There are also U-joints in the front axle shafts on each side, behind the wheels.
🎬 Watch: How to replace front axle shaft U-joints and rotors.What are common mistakes when ordering?
The biggest mistake is getting the wrong size. GM used different U-joint series (like 1310 or 1350) and cap sizes over the years. It is best to measure your old U-joint's cap diameter and overall width before ordering. Some owners take the old part to the store to match it up visually.
Can I replace a U-joint myself?
Yes, this is a DIY-feasible job for someone with mechanical experience and the right tools. You will need a good socket set, snap ring pliers, a hammer, and either a bench vise or a ball joint press to push the old joint out and press the new one in. It can be difficult if the old joint is rusted in place.
🎬 See this step-by-step guide for changing U-joints in your driveway.What are TSBs or Recalls for K1500 U-joints?
There are no specific recalls or Technical Service Bulletins (TSBs) from the NHTSA for universal joints on the 1979-1987 GMC K1500. Recalls for driveshaft issues on GM trucks are for much newer model years and different problems, like improper welds.
Helpful Videos
Technical Specifications
Common U-joint series for this application include 1310 and 1350. The front axle shafts often use a specific U-joint like the Dana Spicer 5-760X. It is critical to measure bearing cap diameter and width to ensure correct fitment.
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.