Ford Custom 500 Universal Joint Guide: 1970-1977
Keep your classic Ford running smoothly by diagnosing and choosing the right replacement U-joint.
- A clunk when shifting or a vibration at speed are the most common signs of a bad U-joint.
- For reliability and strength, Dana Spicer is the most recommended brand for classic Fords.
- Measure your old U-joints before ordering; parts may have been swapped over the decades, and sizes can vary.
- Driving with a failing U-joint is dangerous; a complete failure can cause the driveshaft to detach from the vehicle.
Symptoms of a Bad U-Joint
A failing U-joint gives several warning signs. Ignoring them can lead to the driveshaft breaking free while you drive, which is extremely dangerous. Listen and feel for these symptoms:
| Symptom | Description |
|---|---|
| Clunking or Banging Noise | A loud 'clunk' when you shift into drive or reverse is a classic sign of a worn U-joint. The extra slack in the worn joint causes the driveshaft to bang as power is applied. |
| Vibration While Driving | As the bearings wear, the driveshaft can become unbalanced, causing a vibration that you can feel throughout the car. This vibration often gets worse at highway speeds. |
| Squeaking or Chirping | A rhythmic squeak that changes with your speed often points to a U-joint that has lost its grease. The needle bearings inside the caps are running dry, creating a metal-on-metal squeal. |
| Visible Looseness or Rust Dust | If you can safely look under the car, check the driveshaft. Try to twist it by hand (with the car in park and parking brake on). If you feel any play or see reddish-brown dust around the U-joint caps, the joint is likely bad. |
Choosing the Right Aftermarket U-Joint
For a classic car like the 1970-1977 Custom 500, new original equipment (OEM) parts from Ford are no longer available. All replacement options are from aftermarket manufacturers. Quality varies, so it's important to choose a trusted brand.
Brand Quality Tiers
| Brand | Tier & Reputation |
|---|---|
| Dana Spicer Chassis | Top Tier: Spicer is widely considered the gold standard for U-joints, often exceeding original quality. They were an OEM supplier for many manufacturers and are the top recommendation in numerous forums for their strength and durability. If you want the best, most reliable part, choose Spicer. |
| Moog | Mid-to-High Tier: Moog has a long-standing reputation for quality suspension and driveline parts. However, some users report that quality has become inconsistent in recent years. They are generally a solid choice, but many experienced mechanics prefer Spicer for U-joints. |
| ACDelco | Mid Tier: While strongly associated with GM, ACDelco produces parts for many makes and models. Their Professional line offers good quality aftermarket replacements that meet original specifications. They are a reliable option if Spicer or Moog are not available. |
| GMB | Economy Tier: GMB is known as a budget-friendly brand. While functional, they are not typically regarded as being in the same quality league as Spicer or Moog. For a vehicle that is driven regularly or has a powerful V8 engine, investing in a higher-tier brand is recommended. |
Pro Tip: Greaseable vs. Non-Greaseable
You will see options for both "greaseable" (with a zerk fitting) and "non-greaseable" (sealed) U-joints. Non-greaseable joints are typically stronger because the cross is solid metal, without a channel drilled for grease. They are also maintenance-free. Greaseable joints can have a longer life if, and only if, they are greased regularly. For most owners, a high-quality, non-greaseable Spicer U-joint is the strongest and simplest choice.
Frequently Asked Questions (FAQ)
How many U-joints does my Custom 500 have?
Most 1970-1977 Ford Custom 500 models have a simple, one-piece driveshaft with two universal joints: one at the transmission and one at the rear axle. Some station wagon models or those with longer wheelbases might have a two-piece driveshaft, which would have three U-joints and a center support bearing.
Is replacing a U-joint a DIY job?
It can be, but it requires some specific tools. Removing the old joint often requires a bench vise and sockets or a dedicated U-joint press. It can be difficult due to rust. If you are not comfortable with this kind of work, a professional mechanic can do the job in an hour or two.
Do I need to get my driveshaft balanced after replacing the U-joints?
If you are just replacing the U-joints, balancing is not usually necessary. However, it is critical to mark the driveshaft's orientation to the axle yoke before you remove it and reinstall it in the same position. This preserves the original balance. If you still have a vibration after replacement, the driveshaft may be out of alignment or have other issues.
What is the most common mistake when ordering a U-joint?
The most common mistake is ordering the wrong size. Over the years, parts may have been swapped. It is highly recommended that you measure your old U-joint's cap diameter and width before ordering. A common size for these Fords is the 1330 series, which typically has a width of 3.625 inches and a cap diameter of 1.062 inches, but you must verify this on your specific vehicle.
Technical Specifications
The most common U-joint series for this vehicle are the 1310 and 1330. A common measurement for the rear U-joint is a 3.625-inch outside snap ring dimension with a 1.062-inch bearing cap diameter. However, due to production variations and previous repairs, you must measure your existing parts to ensure you order the correct replacement.
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.