I noticed a pool of fluid under the truck yesterday and thought right away about an oil change 2 days before... but the drip was 2/3 way back of the truck.
Found this plastic wrapped in there and also melted on exhaust pipe. I now remember a smell thinking back. Anyway, I figured the rear gear case could be a pint low and ok to go for beer. also been noticing more clunks putting into gear or reverse, so those 25 year old U-joints probably needed changed anyway. I am considering doing this work, I'm 66 but still able. anything I should know (tip) ? also i'm assuming there is a bearing going into that front of the case (pumpkin) that is spewing the oil ? thanks

 

Make sure you check the axle nut torque proper. As I understand the seal is from the pressure on the bearing itself more than anything. When the axle nut loosens you will start to puke oil out the front of the case. Also look at the breather on the top and make sure its clear. If that gets plugged you can get oil forcing itself out of the the seals. Think like a failed PCV. Last time I did a set of U-joints on my Dakota one of the caps exploded and put a hole in the wall behind me. (Had to use a press since the driveshaft side was seized.)

 

thanks, I 'm seeing a flange oil seal is in there, must be a front and back (each end of drive shaft ) ?

 

The transmission side I believe is sealed inside the trans. The yoke on the transmission side if I remember correctly splines into the tail housing and a small amount of trans fluid weeps out and provides lubrication. This is the small amount of fluid that spills out when you pull the shaft all the way out. The splines themselves are the seal for that side. The differential side has a flange seal and bearing set. The bearing prevents most of the gear oil from leaving. The flange seal is mostly to prevent contamination from getting in. I don't remember the exact science behind it though so you might want to wait for magnet or one of the other more experienced guys to chime in.

 

The plastic likely wrapped around there, and trashed the seal, so, yeah, changing it would be a real good idea. Did your truck have the recall for the pinion nut?? Might wanna check on that. And yes, proper torque back there is CRITICAL. Do it wrong, and you'll trash the entire rear end...... (cheaper to replace than rebuild.)

 

that sounds right, thanks . the front at the yoke did seep a little, never leaving a drip on driveway.
so, hopefully I am looking to get a flange seal for 8.25" diff. and two Moog 238 universal joints. ?
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