Quadra-Trac Borg Warner 1339 Transfer Case Parts Jeep CJ7
Vacuum switches, oil seals and yoke hardware for the full-time four-wheel drive (1976-1979).
Why the Quadra-Trac holds a special place in the CJ7.
With the CJ7, full-time four-wheel drive reached the CJ line for the first time in 1976: unlike the part-time Dana units, the BorgWarner Quadra-Trac worked with a differential inside the transfer case itself and was available exclusively with the Turbo Hydramatic automatic. The aluminium housing saved weight, and the low range sat behind it as a separately bolted-on unit. After four decades, three areas in particular ask for attention. The seals at the shaft outputs harden, so oil escapes at the yoke and the fluid level drops unnoticed. The vacuum control that actuates the front axle engagement loses its function once the switch turns porous. And the yoke hardware works loose whenever nut and lock washer were reused at the last removal – a mistake that announces itself as a clunk in the driveline.
The wear parts we keep in stock for you
- Vacuum control: If the front axle engagement no longer responds, the transfer case vacuum switch is usually to blame – it switches the vacuum signal at the case and is a classic suspect when the shift fails to act.
- Sealing the shaft outputs: Against oil loss at the yoke, fit the output shaft oil seal, which serves at the front and rear output as well as on the axle side.
- Yoke hardware: Every time the propeller shaft comes off, the pinion nut and its lock washer should be renewed – both are single-use items whose clamping force is no longer reliable once undone.
Crown Automotive and Dana Spicer as suppliers.
The vacuum switch and the output seal come from Crown Automotive, the US specialist for keeping classic Jeep models supplied. Pinion nut and lock washer are made by Dana Spicer – the very manufacturer that originally built the axles and transfer cases of this era. American original equipment quality exactly where dimensional accuracy and clamping force decide how long the joint holds.
Which transfer case is in your CJ7?
Whether your vehicle left the factory with a Quadra-Trac, a Dana 20 or a Dana 300 can be identified clearly from the tag and the housing – we are glad to help you pin it down before you order, and to answer questions on torque figures and assembly sequence. Dispatch is from stock in Germany and goes out shortly after your payment arrives.