Pinion nut torque and flange play

[91stranger]

So I've been messing with this rear end for a week or so now. Originally it was a bad pinion seal that blew. Well I messed up by not using a paint marker to mark the pinion nut before I took it off. Instead I used a Milwaukee sharpie and counted the threads and tightened the nut to see how tight it was. I did NOT check the flange to see if there was play before removing the nut. Well I got the new seal in and tightened the nut back to where it was but when I drive I get a slight growl sound coming from the rear and I can feel a very slight vibration in the floor whenever I let off the gas anytime above 40 mph. Goes away as soon as I give it gas too. I got the nut back to the same amount of threads and it is damn near as tight as I can get it with a 1/2" socket wrench. I'm scared to over tighten it and mess up the crush seal. Should this flange have any bit of side to side play? Right now it has about 1/8" if that side to side and ZERO play front to back. I am just running out of options on this and don't want to put a lot of money into it if I need to just get a different rear end. Any help would be appreciated. Thanks.

 

[Dirtman]

Well short answer... no the flange should not have side to side play at all. That would be a pretty clear indication the bearing is toast. Which, if it got low on oil, the pinion bearing would be first to go.

 

[Shran]

At this point you have nothing left to lose but to try and tighten it some more. It should have no play at all side to side or in/out.

The crush sleeve requires quite a bit of torque to crush, I'd try tightening it up more with a breaker bar/cheater pipe or whatever you have on hand.

 

[91stranger]

That's what I was thinking too. I've watched videos of people using impacts on these and I'm hesitant to put my 1200 ft/lb impact on it. Breaker bar it is. I can still tighten it some I just wanted to leave a little play. I thought it was supposed to move just a cunt hair. There's not a lot of videos about pinions and the proper way to work on them. I ended up finding a very detailed video and the guy broke it down with the parts pulled from the diff and it made a lot more sense to me when I saw it all pulled out. So I guess I will tighten it down so there is ZERO play. Hopefully I can get this back on the road. Seems like you never need a truck until it is down. Now I have a few trailer loads of scrap to take in, bunch of trash to throw out and does anyone else notice that you never see rangers until your not driving one? I see them all the time now that I'm driving the back up car. Thanks fellas

 

[Dirtman]

I agree... crank that bastard down. Can't hurt at this point. Can you even feel any preload when turning the flange?

 

[91stranger]

I've never messed with pinions or pre loaded bearings until this happened so I don't know what I need to be checking. Everything I have done so far has been bass-akwards and fighting rust with everything. Right now I am going to crank the sum beech down to the point of no pay at all and see what happens. If I still get noise/vibration after tightening this down then it will be rear end shopping... Which I've already been doing but I keep hoping to find one of my buddy's old derby cars or junk yard.

 

[Shran]

I'd take it slow, tighten in small increments until you are satisfied. You are basically using the nut to pull two bearings together. Any slop in/out or side to side is bad but you don't want to tighten so much that it destroys the crush sleeve or is so tight that you can't turn the pinion.

 

[adsm08]

When you say "side to side play" do you mean axial or radial?

 

[Uncle Gump]

I think at this point... I would just take the impact to it with the rear up on jack stands. Give it short bursts... while checking the flange and rotating the rear end.

As Shran said... it takes a bunch of torque to get the crush sleeve to crush... way more then the proper pinion nut torque.

 

[Dirtman]

The crush sleeve should have already been crushed. It "should" just be a matter of re-installing the nut to the same depth. Whether its rust making it hard to re-install the nut, or the bearing worn enough to require more preload to take up the slack I dunno but there's definitely something wrong here.

 

[Uncle Gump]

I totally agree...

 

[19Walt93]

I've replaced many pinion seals without replacing crush sleeves but the manual says you're supposed to. The pinion bearings should be under preload so you can feel drag when turning the flange, if it's a little too tight it will work OK, if it's a little loose it will kill the bearing.

 

[91stranger]

So I took the ol 1200ft/lb impact gun to the pinion nut and it tightened down about another 1/8 turn or so. Took it for a test drive and it is better but it still makes a grinding sound as soon as I let off the gas at any speed above 45mph. When driving below 45mph it doesn't sound bad at all when I let off the gas and actually sounds like it is supposed to. I just don't understand why this is giving me such grief. I will say my impact battery wasn't fully charged so it probably didn't have enough balls to run it in tighter. I am planning on trying to tighten it a little more and see if that helps. U-joints are rusty but there is no play in them at all. It is a one piece drive shaft so no carrier bearing (that's what it reminds me of) and fluid is where it should be. I would love to drive my truck instead of the PT nightmare I've been driving but don't want to ruin anything. When this first happened it felt like a bad front wheel bearing but I spun both front wheels and they spin easily with no odd sounds or any play other than the ball joint play that I need new ball joints for but that wouldn't cause the grinding sound when I let off the gas.

Question... Do I need to brace the flange while tightening the pinion nut or can I just tighten it with the wheels on the ground and choked to keep it from rolling? I have been tightening it with the flange braced but I bent the metal bar I made to hold the flange so I either have to make a new one or if I can tighten it without bracing the flange... I'd hate to buy a rear end if there was something wrong up front like wheel bearing or something else that I am missing. It's 2wd so no transfer case either.... I am just at a loss and it's not like I can ride underneath it and listen when it happens.....

 

[Shran]

Did tightening the pinion nut remove any of the slop?

You only need to have the flange braced if you're using something other than an impact to tighten the nut... but you can sometimes stick a big bolt through the holes in the flange to hold it against the axle. You can also set the e-brake with the wheels on the ground, that should keep it in place.

 

[91stranger]

I was able to get it to tighten about another 1/16 of a turn but still getting grinding sound above 45 when I let off the gas. When I tightened it with the impact I couldn't move it at all by hand so I figured it was good but apparently not. Could I have a different issue other than the pinion nut? u joints are old but have no play. I think I'm at the point of needing to pop the diff cover off, again, to inspect the pinion bearings to see if they have wear on them. Anything else I could check?