4 Speed Jeep T18 Synchro Kit 1967-78 You can identify this transmission by the casting "T18" or "13-01" and it has an iron case. NOTE: It is important to measure the key slots for your 3rd and 4th synchro rings to make sure you get the correct rebuild kit. This synchro kit comes with 3rd and 4th synchro rings that have 13mm key slots. If your 3rd and 4th synchro rings have 10mm key slots, please see my other listings for the correct kit for you. SRK114J