[ES 3000TT]

Brett The 18 spline shaft I got and the 25 spline shaft i just cut off were totally different! The 25 spline can't be replaced with an 18 because the shaft is smaller and will wiggle around inside the transmission. Then the 25 spline wont fit inside the 18 because its too big. The 25VCU compared to the 18VCU I received as well was different. The lip on the bottom was longer. opposed to the 25 spline VCU that had no lip. I ended up hooking my fathers AWD back up on his 25 spline transmisson but it took some grinding of the old 25 spline vcu middle gear set and eating away some of his inner teeth on top of the 18 spline VCU. The Middle gear sets are different. the 18 is longer and the 25 spline is shorter. The 18 gearset also has the teeth all the way up to the set where the Planetaries run on. Opposed to the 25 spline middle gear set that the teeth end like 1/4 inch before the teeth for the planetary gears. The 18 vcu also has the inner teeth all the way up and down the inside. opposed to the 25 that doesn't. This is all on the five speed! haven't cracked a 6 speed open yet! 18 spline shaft is thinner then the 25 spline thicker shaft