AMC 20 pinion angle and fluid starvation

tankcj

Anyone have a steep pinion angle and experience any pinion bearing lubrication problems? I have my pinion rotated up 12 deg and wonder if I'll have any problems with the pinion bearing not getting enough fluid when driving at high speeds (hiway). I suppose I can over fill it slightly???

tufcj

I run my Dana 44 in my CJ tilted up at about 14 degrees. I've had no problem with over 20K miles on it. I fill it till fluid runs out the fill hole and use synthetic lube. The design of the oil passages in any rear uses the ring gear as a slinger to carry oil to the front pinion bearing. Bob tufcj

tankcj

I tend to agree with you. With that much fluid in a small area it's bound to get slung around a bit. I think Fuzz has something like a 23 degree angle in his d44 and I didn't see anything in his past posts about that being a problem.

tufcj

If you've ever had an axle open, there's a passage cast into the housing that starts at the top of the ring gear, and ends between the pinion oil seal and the front pinion bearing. As the ring gear rotates, oil is slung off the top into the passage, it runs down thru the front bearing to get back into the diff. I don't see that there would be a problem unless the pinion was pointed so far up that the entire passage was up hill. That would probably make the pinion higher than the top of the housing. Bob tufcj

youdidwhat

Don't know if this will help but sometimes for High angle diffs you can jack the back up to a more-so level point and add till full then bring it back down after closeing it up this will ensure the full amount of fluid and still keep that sweet angle. Just another old trick that some remember now and some remember later Hope this helps.

tufcj

Actually, the AMC 20 fills from the front. The plug is on the drivers side near the yoke. Tipping the pinion up would just aid in overfilling. The only drawback would be if the inner axle seals aren't good, you'll oil the brakes. Bob tufcj

youdidwhat

tufcj wrote
Actually, the AMC 20 fills from the front. The plug is on the drivers side near the yoke. Tipping the pinion up would just aid in overfilling. The only drawback would be if the inner axle seals aren't good, you'll oil the brakes.

Bob
tufcj

thank you I have yet to work on an AMC 20. and that is good info.

tankcj

thanks tufcj!...that what I wanted to hear!!