Extension housing oil seal – replacement
Note: This procedure also applies to the transfer case extension housing seal on 4WD models.
1. Oil leaks at the extension housing oil seal are usually caused by a worn seal lip. Replacing this seal is relatively easy, since you can do so without removing the transmission from the vehicle. The extension housing oil seal is located at the rear tip of the transmission extension housing, where the driveshaft is attached. Note: If the vehicle is a 4WD model, there is no extension housing. Instead, the transfer case is bolted to the rear of the transmission housing. But the following procedure applies to replacing the rear seal on 4WD models as well.
2. If you suspect that the extension housing seal is leaking (because you’ve seen puddles below the extension housing seal and/or because the transmission seems to be losing lubricant), raise the vehicle and support it securely on jackstands. If the seal is leaking, gear lube will be oozing or dripping from the rear of the transmission, coating the forward end of the driveshaft and leaking onto the ground.
3. Remove the driveshaft (see Clutch and driveline).
4. Some seals have a metal casing with a lip. With this type of seal you can use a chisel and hammer to carefully pry the oil seal out of the rear of the transmission (see illustration). Do not damage the splines on the transmission output shaft.
2.4 Use a hammer and chisel to dislodge the rear seal from the extension housing on 2WD models (shown) or, on 4WD models, from the transfer case
5. If the seal doesn’t have a metal lip, obtain a special oil seal removal tool (available at most auto parts stores) to do the job.
6. Using a seal driver or a very large socket as a drift, install the new oil seal (see illustration). Drive it into the bore squarely and make sure that it’s completely seated.
2.6 Use a large socket (shown) or a seal driver to drive the new seal into the extension housing (shown) or transfer case. The outside diameter of the socket must be slightly smaller than the outside diameter of the seal, just enough to clear the edges of the seal bore
7. Lubricate the splines of the transmission output shaft and the outside of the driveshaft yoke with lightweight grease, then install the driveshaft (see Clutch and driveline). Be careful not to damage the lip of the new seal.