This procedure covers the removal and replacement of universal joints (U-joints) in the driveshaft of a 1966 Chevrolet Corvette with 327ci V8, including driveshaft removal, U-joint pressing, and reinstallation.

Warnings

Tools required

Parts

• Universal joint (U-joint) kit with snap rings × 2 — Spicer 5-260X or equivalent 1310 series
• Rear differential gasket or RTV sealant × 1 — Use OEM specification

Fluids

• 75W-90 GL-5 Gear Oil — 2 qt

Preparation

1. Park vehicle on level surface and chock front wheels securely
2. Ensure transmission is in neutral and parking brake is OFF
3. Raise rear of vehicle and support securely on jack stands under frame rails behind differential
4. Allow exhaust system to cool completely if vehicle was recently driven
5. Clean area around rear U-joint and differential yoke to prevent contamination

Procedure

1. 1

   Mark driveshaft orientation
   Using marking crayon or paint pen, mark the relationship between the driveshaft yoke and the differential pinion yoke. Draw a line across both flanges so they can be reassembled in the exact same position. This prevents driveline vibration issues. Also mark the driveshaft tube to the front yoke for reference during U-joint installation.
2. 2

   Remove rear U-joint strap bolts
   Remove the 4 U-bolts or strap bolts securing the rear U-joint to the differential pinion yoke. These are typically 7/16" or 1/2" heads. Support the driveshaft by hand as you remove the final bolts to prevent it from dropping. Note the orientation of any washers or lock washers for reassembly.
3. 3

   Remove driveshaft from vehicle
   Carefully slide the driveshaft rearward to separate the rear U-joint from the differential yoke. Once clear, pull the front slip yoke out of the transmission extension housing. Keep the driveshaft level to avoid spilling transmission fluid. Place drain pan under transmission extension housing to catch any fluid drips. Stuff a clean rag into the extension housing to prevent fluid loss and contamination.
4. 4

   Remove rear U-joint snap rings
   Position the driveshaft on a clean workbench. Using snap ring pliers, remove the internal or external snap rings (depending on yoke style) from all 4 bearing cap grooves on the rear U-joint. Use a magnetic pickup tool to retrieve any dropped snap rings. Inspect snap rings for wear or deformation; replace if installing new U-joints.
5. 5

   Press out rear U-joint bearing caps
   Using a U-joint press or bench vise with appropriately sized sockets, press one bearing cap out of the yoke. Position a larger socket against one bearing cap and a smaller socket on the opposite side to receive the cap being pressed out. Press slowly and steadily. Remove the partially ejected cap, then rotate the yoke 180 degrees and press the opposite cap out. Once two caps are removed, the U-joint cross can be removed from the yoke, then remove the remaining two caps from the driveshaft tube yoke.
6. 6

   Clean yoke bores
   Thoroughly clean the bearing cap bores in both yokes using a wire brush and shop rags. Remove all old grease, rust, and debris. Inspect bores for damage, scoring, or excessive wear. Check that yoke ears are not bent or cracked. Any damage to the yoke requires driveshaft replacement.
7. 7

   Install new rear U-joint
   If the new U-joint has grease fittings, orient the cross so the fitting will be accessible after installation. Start one bearing cap into the yoke bore by hand, ensuring needle bearings remain in place. Insert the U-joint cross into the partial cap, then start the opposite cap. Use the U-joint press or vise to press both caps into position until they seat against the snap ring grooves. Do not press beyond the snap ring groove. Install snap rings in both caps, ensuring they are fully seated in their grooves. Repeat for the other yoke, then install remaining snap rings.
8. 8

   Remove front U-joint (if replacing)
   If the front U-joint at the slip yoke also requires replacement, repeat the snap ring removal, pressing, and installation process described in steps 4-7 for the front U-joint. Ensure proper phasing: both yoke ears on the driveshaft tube should be in the same plane (aligned with each other) to prevent vibration.
9. 9

   Lubricate new U-joints
   If the U-joints have grease fittings (zerk fittings), use a grease gun to pump fresh chassis grease into each joint until grease appears at all four bearing cap seals. Wipe away excess grease. If U-joints are sealed type without fittings, no lubrication is needed.
10. 10

    Reinstall driveshaft to transmission
    Remove the rag from the transmission extension housing. Apply a thin coat of transmission fluid to the slip yoke splines. Carefully insert the slip yoke into the transmission extension housing, ensuring the splines engage fully. Slide the yoke in until it seats against the internal snap ring inside the extension housing.
11. 11

    Connect driveshaft to differential
    Align the rear U-joint with the differential pinion yoke, carefully matching the alignment marks made during disassembly. Position the U-joint bearing caps into the yoke saddles. Install the U-bolts or strap bolts with any washers in their original positions. Hand-thread all 4 fasteners before tightening.
12. 12

    Torque rear U-joint fasteners
    Tighten the 4 U-bolts or strap bolts in a cross pattern to ensure even clamping. Torque the fasteners per the 1966 Corvette factory service manual specification (verify exact value before final tightening; do not rely on a generic guess). Double-check that all fasteners are tight and that the U-joint bearing caps are fully seated in the yoke.
13. 13

    Check differential fluid level
    Remove the differential fill plug and check fluid level. Fluid should be at the bottom of the fill hole. If fluid was lost during driveshaft removal, add GL-5 80W-90 (or 75W-90) gear oil until it reaches the proper level. If the differential is a Positraction limited-slip unit, include the manufacturer-specified limited-slip friction modifier additive. Reinstall fill plug securely.

Reassembly

1. Verify all U-joint snap rings are fully seated in their grooves
2. Confirm driveshaft alignment marks match original orientation
3. Ensure all U-bolts or strap bolts are torqued properly in cross pattern
4. Check that slip yoke is fully engaged in transmission extension housing
5. Remove jack stands and lower vehicle to ground

Verification

• Start engine and shift transmission through all gears while stationary to verify proper engagement
• Test drive vehicle at various speeds, listening for clicking, clunking, or vibration that would indicate improper U-joint installation or driveshaft phasing
• Perform test drive on smooth road first, then on varied surfaces to check for vibration at different speeds
• After test drive, re-inspect all U-joint fasteners for proper torque and check for any fluid leaks at transmission extension housing
• Check under vehicle for any dropped snap rings or tools left behind

More procedures for this vehicle