Required companion to SYE. Double-cardan (CV) joint at the t-case end allows steep operating angles without binding. Tom Wood's and Adams are the canonical vendors.
After installing an SYE, the rear driveshaft must accommodate large operating angles between the t-case and the rear pinion. A standard single-joint driveshaft binds and vibrates. The solution is a double-cardan CV-joint driveshaft, which can run at angles up to 20-25 degrees without vibration when paired with proper pinion angle.
Two vendor archetypes:
Tom Wood's Custom Drive Shafts: built to your measured length, 1310 or 1330 joint, balanced. The XJ DIY standard for two decades. $350-550 typical. Lifetime warranty. They walk you through the measurement and can recommend pinion angle.
Adams Driveshaft: heavy-duty Wrangler-grade builds, sometimes overkill for an XJ but bulletproof. $450-700.
DIY: yes, with patience. A used CV driveshaft from a TJ or ZJ can be measured, cut to length, rebalanced at a local driveshaft shop. $150-300 if you do the legwork.
Measurement: from the center of the t-case output yoke (after SYE) to the center of the pinion yoke (at the axle), with the truck at ride height and full suspension droop checked separately for plunge clearance. Tom Wood's has a measurement worksheet.
The CV driveshaft also requires proper pinion angle on the rear axle — see drive-pinion-angle entry. Wrong pinion angle plus a CV driveshaft = driveline vibration that no balance shop can fix.
Do not skip this after SYE. The point of the SYE is to use a CV driveshaft; running an SYE'd t-case with a normal slip-yoke driveshaft is worse than stock.
| Part | Vendor | Est. price |
|---|---|---|
| Tom Wood's CV rear driveshaft | Tom Wood's | ~$450 |
| Adams Driveshaft 1310 CV | Adams Driveshaft | ~$580 |
Written and maintained by an AZ wheeler and driveway wrencher. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.