I've done some searching but still have a couple questions. 2005 F250 V8/81k miles. It had been leaking barely for a long time but recently got worse enough that I could see a small puddle under the truck, so time to do it. This truck is old and rusty being upper midwest so it is a mess to get apart but I finally got it all apart tonight. I see a nice groove in the pinion flange where it seals, so that needs to get replaced.

First question is how do deal with the new part? I marked everything to put it back together in the same orientation, but now with a new part not sure if that matters or not. Probably the same issue with putting the nut back on. I don't drive this more than a couple thousand miles a year so not too deeply worried but I don't want it failing again before I get rid of it in 2-4 years. Any guidance on this?

Then the fill port. I managed to get the plug out (barely) but it seems way too low on the pumpkin to be right...but there is no other plug I can find. See pic. Is this actually it? Can I get 3.3 L of gear oil in there? Looks like a lot of fun to get in there with an oil jug too...

Thanks for any help,
Dave

 

Yeah, that's the plug. Its just a little higher than the bottom of the axle tubes. The oil is going to flow all along the axle tubes and fill in the oil sumps out at the hubs also. Best thing is to jack the drivers side and tilt the axle, fill to refusal and plug, then lower the axle, now jack the passengers side and tip oil into the drivers sump, then lower and jack the drivers side again, pull the plug and top it off to refusal again. That will get you just a little extra in the diff and ensures good oil transfer for cooling of the bearings and extended oil life.

 

Thanks. Makes sense. Any thoughts on the new pinion flange and setting the nut?

-Dave

 

Setting the nut is normally done by setting the drag torque value of the pinion alone, too little drag and you tighten the nut a shade more, too much, start over with a new crush sleeve. A shade tree method would be to clearly mark the threads and exact position of the nut vs pinions, remove, and then re-install with the same crush sleeve to that exact spot. If you didn't mark it you just going to have to wing it and tighten it until you lack slop in the pinion and it looks like the same amount of threads are sticking out of the nut.

 

Thanks. I did mark it before disassembly and did my best to get it back to the same spot. It is hard to tell if I got it exactly right but it seems pretty good. Test drive was good with no noise or vibration, so hopefully that is done for the life of the vehicle now.
Thanks for your help.
Dave