Twodiesels

Does anyine know the part number for replacement pinioin seal. A friend and I replced the seal yesterday, and now I have fluid puddling. It is worse than before. I thought it was the wrong seal when we put it in but he said it fit. The part # that came out is 50574 and noone seams to have this part at any auto part store. I had never changed one, and he had, so I had him help. But I don,t think it was dfone right. Makes a whinning sound now and when we pput the driveshaft back on the yoke we had to put transfer caser and truck in neutral to turn it so we coulkd align it. I told him to put it back the same way. he said it didn't matter. Now i am ticked.

KATOOM

Turning the driveshaft at the tranny to get the yoke to align up with the rear is OK. What I think you are affraid of is getting the u-joints out of time. That only happens when you have a driveshaft that comes apart. Meaning u-joints on both ends with a slip yoke between them. Then you have to make sure the driveshaft stays together the way it was balanced and the u-joints have to stay in a line (time) or you will get vibration and failure. Unless your talking about the front driveshaft. Are you? Then yes you need to be carefull not to seperate the driveshaft. As for the seal, I dont understand why you are having trouble finding it. Dana parts are everywhere. Just make sure it fits right on the yoke and is all the way in the housing when installed and you need to take some wheel bearing grease, lube up the pinion surface then lay some grease in the V of the seal so it doesnt burn up. Or it will probably leak.

KennyL

Also did you tighten everything to spec? If the pinion nut isnt tightened correctly you will cause the pinion depth to change causing the whine.

wv smoker

I wouldn't drive it if it is making noise until you correct the problem. Sounds like you did not get it tight enough or changed the pinion depth. Were there any shims or spacers behind the yoke? Did you use a new pinion nut? Don't recall the tightening torque, but you must foul or hold the yoke when tightening the nut, don't put pressure on the gears as they will probably be damaged. Seals can usually be found at NAPA or most auto stores, sometimes a groove is worn in the yoke and the seal won't work without putting a sleeve around the yoke. Also can usually be found where you buy the seal.

high country

Did you replace the CRUSH SLEEVE???? they set pinoin preload and only get used once. It takes a quality 1/2" impact like an Ingersol to get them started. you will be best off to have an inch/lb wrench handy too, if you have noise and fluid this would be my vote....oh and stop driving!!!!!!! get you pinion preload right before you lose the yoke...walk the pinion through the ring gear and grenade a housing$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

jughead

to the best of my knowledge there is no crush sleeve in a dana 44 and larger rear end.

CTD NUT

There should be no crush sleeve on a D70/80 rear.......pinion bearing preloading is set with shims..........The pinion nut must be torqued to about 500 ft/lbs on a D80.........not too many 1/2 impact guns are capable of this........I would suggest the appropriate torque wrench and set the parking brake.......it is also common practice to replace the nut everytime it is removed........

latitud_rt

Don't forget red loctite. You most likely will need a 4ft pipe to get the torque you need.

Twodiesels

Well guys we fouled it up big time. I had to go put a shoe back on a horse and drove it about fifty miles round trip. When I got home I took it back apart because it was leaking bad. Wrong seal, knew it was but friend said it would work. Then we tried to push it out of the way to get my other truck out of shopand the rear end locked up. Could not turn the axle at all. Pinioin slid back to far when we started to push it. Today my mechanic came over and the front bearing is shot. Pulled bearing and still couldn't turn. Then pulled shaft forward and it started to role. Pulled diff cover off and noticed a tiny bit os metal fragments on the magnet. It looked like also that the back bearing was slid back. I really don't know what to do. I am an idiot with a wrench and am trying to get her back on the road. All the teeth look fine on gear.
Also I had to pull driveshaft out of transfer case. I noticed when shifting into neutral/park it grinds a little too. Is this normal with the driveshaft out of it?

high country

Sorry for your loss and the brain spazm on the crush sleeve

CTD NUT

You have probably not damaged the ring and pinion by sucking the pinion into the ring gear........it should be fine.......the back bearing slides over the pinion shaft and should move around with the pinion if it falls out......If I were to guess, I would say your lower pinion bearing is fine......just replace the outer.........technically, to set the proper pinion bearing preload after a bearing is replaced, you would have to remove the carrier so that you can test for preload with out spinning the carrier.........proper preload of all rear end bearings is critical.......in your case, I would replace the front bearing and reuse the existing shims but drive the truck directly to a reputable shop that works on axles.......the proper preload should be set.......IMO, I would spend the money to have all the ring and pinion tolerances checked and reset.......normal wear and tear can throw them out of wack over time.

It is normal for your auto to be making noises shifting into park without a load on it (no driveshaft)........it is hard on the park pin, though so try not to do it.

KATOOM

Save yourself some time and money. Take it to someone who knows the ins and outs of differentials. These are not for the weekend mechanic and are very easy to screw up. Funny thing is they seem fine and put together right then 100 miles or so down the road you hear noises or worse some banging and clanking followed by expensive repair bills. It might cost a few bucks but you get the peice of mind knowing that its most likely done correctly and if something does go wrong you can take it back.

Dieselholic

I agree, take it to a garage where they work on semis or heavy equipment. I had mine replaced at a local Cummins garage and was just charged $53.00 labor,I already had the seal,that I had picked up at the ******* for $28.00. According to the dealer there is many pinion seals for this truck since anything from a Dana 60 to a Dana 80 is under it. If its an auto trans your should have a Dana 70, manual trans It should be Dana 80. All 3500 have Dana 80 regardless of trany. The job seems easy but, using a puller and cleaning up your yoke with either emery cloth for light scars or 1500 sand paper for heavy scars then torque down to 480-520ftlbs. Hope this helps.