I have a couple of questions:
- When I went to drain the differential, I removed the fill plug first and some fluid came out. It seems like that wouldn't be possible?
- I am trying to understand how the axle bearings are lubricated. When looking at the rear of the axle/differential assembly, it doesn't seem like the fluid level would get high enough to lubricate down the axle. And the bearings aren't sealed in any way, so I am assuming they are completely reliant on the differential/axle fluid for lubrication.
Also, while troubleshooting the parking brake (it still doesn't "work") I noticed this seal on the drive shaft was not screwed in (see photo attached). I attempted to get it back on multiple times and was unable to get the threads to engage. I tried to clean both thread surfaces, but to no avail. I assume the seal sits against shaft coming from the transmission and not "inside" of it, if that makes sense? Anyway, I put the truck away to tackle it another day. But any thoughts welcome.
Some hopefully helpful response to your questions:
"- When I went to drain..." - Yes it is entirely possible for there to be too much oil in your axle. Usual culprit is a failed front torque tube oil seal (behind the front driveshaft bushings) that lets oil from the transmission migrate down slope in the torque tube to the differential housing. The fix is to replace the front torque tube bushings and oil seal, unfortunately.
"-Iam trying to understand..." - Here's an very old
on-topic thread that sums up how the axle bearings get lubrication, without a lot of technical terms - lol!
"...I noticed this seal on the drive shaft..." - In looking at the picture, it appears your transmission is kinda sagging down just a tad, and is most likely causing the difficulty with getting the seal collar nut to thread back on. You might be able to realign the collar output tube by hand to realign. If not, I think if you put a jack under the transmission tailshaft housing (not the ball collar assembly) and gave it just a little lift, you should be able to restore alignment and thread it back on. Your transmission rubberized mount is likely oil damaged/compressed, causing this issue. Yes, the seal is compressed against the ball collar output tube to create the sealing effect. Once the collar nut is back in place, IIRC, you need to lightly stake the collar to help keep it from un-threading itself during driving. I had this problem on my truck, but didn't know about the "staking step" to help it stay in place. I must have put it back a dozen times.
