What is this noise?

[Old Henry]

Henry, check your drive line front to back. New motor and ****** mounts snugged down, anti-chatter rods properly installed, correct shackles and spring U bolts cinched up properly. Now check that you have the thrust washer installed at the U joint. All that's left is the coupler, the worn splines, and the pins. Buy a new coupler and new pins. Pick up a drive shaft with better splines, and seriously consider changing out your ring/pinion, or otherwise, cross your fingers.

I agree with the others. Go through the rear end.

Considering that Old Henry doesn't just drive around the neighborhood, I'd be really tempted to do a complete job. FWIW

I agree with Don. Do the job right the first time so hopefully you don't have to do it again later. I would personally take this opportunity to check the complete rear for everything including gear alignment, bearings, seals, etc., etc. There are some good procedures posted on the internet on how to do everything necessary. If you don't feel confident doing it yourself...find someone who can. JMO.

If it were my car I'd be opening it up. I'd want to really take a good look at the pinion bearings and carrier bearings. It doesn't take much metal to score a bearing. By taking it apart you can get it cleaned up inside also, I don't think flushing it out would remove all the metal.
Good Luck
Don

I really do appreciate all of your suggestions to "go clear through" the rear end. I have carefully considered each and every one and studied very completely and carefully this thread on the HAMB detailing how to do it. http://www.jalopyjournal.com/forum/showthread.php?t=462776 I think if I had the confidence and correct tools and hadn't gotten to the point I'd much rather drive it than work on it I'd probably do that very thing. As I don't have the confidence or specialized tools, don't know anyone locally who does, (no - I'm afraid Chuck is not such an one) and need to get the car back on its wheels and on the road as soon as possible I'm probably going to go with my general policy of "if it ain't broke don't fix it." I have had no problems with the differential other than the annoying noises over the last several years that now appear to all be caused by the danged coupler pins.

What I am going to do is order a new lock washer that goes between the pinion nuts since they may well have been moved by the impact of the pin fragments, remove the outer nut, re-torque the inner nut to specs to take up any slack that there may be from bearing wear, re-install the lock washer, put on the outer nut and bend the tabs down to lock it, and, after I get it all put back on the car run the drive line in the air with mineral spirits or solvent in the differential a few times to rinse out the metal flicks, put in new oil with a little added ZDDP as always and drive the wheels off of it again.

I'll also be replacing the brake line from the front T to the hose that goes to the rear axle brake line, the short hose that's in that line, gaskets between the torque tube and banjo, U-joint gaskets, speedo turtle gaskets, track bar and shackle bushings and studs.

I'm still considering replacing the coupler and pins as well as the speedometer cable.

Thanks again for all your help.

 

[PeteVS]

I posted awhile back that I had once read of a fix to drill the torque tube, pull out the loose pin and put a pipe plug in the hole. Looks like that's what ya shoulda done. Now, the questions why did it only rattle in certain circumstances? Could it be that the pinion bearing loosened up? That might allow the pinion to move back and forth making the noise / no noise situation. I'd say you're in for a complete tear down.

 

[PeteVS]

Big difference here between "setting up" a banjo rear and just disassembling, cleaning and reassembling with the same gasket counts. I don't think it's too feasible to reassemble without getting the axles vertical as in that HAMB thread. I don't think it's wise to be leaving little bits of metal in there! IMHO!

PS: I don't think there's any "torque spec" for the pinion nuts. They should be torqued to a bearing preload which you should be able to do by feel. That would be a lot easier to do if the ring gear, carrier and axles were out of the way during that set up. Once again, IMHO!

 

[ford38v8]

....What I am going to do is order a new lock washer that goes between the pinion nuts since they may well have been moved by the impact of the pin fragments, remove the outer nut, re-torque the inner nut to specs to take up any slack that there may be from wear, re-install the lock washer, put on the outer nut and bend the tabs down to lock it....

Henry, DO NOT mess with the pinion lock nuts unless you intend to rebuild the banjo. These locknuts are just that, they are locked, you can see from the pictures thety haven't moved, and those nuts aren't "torqued" anyway. They are tightened to provide a preload on the pinion bearing, the correct preload itself determining how much to tighten the nuts.

 

[Old Henry]

Henry, DO NOT mess with the pinion lock nuts unless you intend to rebuild the banjo. These locknuts are just that, they are locked, you can see from the pictures thety haven't moved, and those nuts aren't "torqued" anyway. They are tightened to provide a preload on the pinion bearing, the correct preload itself determining how much to tighten the nuts.

The guy in the HAMB article showed these specs for tightening the pinion nut.

Granted 8-14 in/lbs is not much torque. I don't know what pre-load on bearings is so tell me some more why not try to adjust that nut to that spec for used bearings to try to take up some slack from wear. I'm here to learn.

 

[PeteVS]

Henry, DO NOT mess with the pinion lock nuts unless you intend to rebuild the banjo. These locknuts are just that, they are locked, you can see from the pictures thety haven't moved, and those nuts aren't "torqued" anyway. They are tightened to provide a preload on the pinion bearing, the correct preload itself determining how much to tighten the nuts.

If, as he says, the pinion shaft is moving up and down under load / no load, the pinion bearings ARE loose and need to be reset.

 

[PeteVS]

The guy in the HAMB article showed these specs for tightening the pinion nut.

Granted 8-14 in/lbs is not much torque. I don't know what pre-load on bearings is so tell me some more why not try to adjust that nut to that spec for used bearings to try to take up some slack from wear. I'm here to learn.

Those are not nut torques! That's what the torque to turn the pinion shaft should be when the the first nut is tightened. Once that first nut is set, the second nut gets cranked up TIGHT!

 

[Rocketsled]

Re: Pre-Load

Pre-load is neccessary on tapered roller bearings to ensure that line-contact is achieved along the length of the rollers.
Ball bearings make point contact and they come with different internal clearances depending on the application conditions, for example at higher temperatures more internal clearance in needed to compensate for expansion.
Roller bearings make line-contact and tapered roller bearings need to be preloaded to ensure that the rollers make full contact with the cup and can thereby take the prescribed load. If too loose, the rollers may rattle, cause wear and not be ready to take a heavy load. If not in full line contact a heavy shock load could fracture things.

 

[ford38v8]

Those are not nut torques! That's what the torque to turn the pinion shaft should be when the the first nut is tightened. Once that first nut is set, the second nut gets cranked up TIGHT!

Pete has it right here. The lock washer slides onto the spline and cannot turn. The locknut cinches up to it, then the lock washer folds over the two nuts, locking them together. You can see in your pictures that the two nuts are still locked together.

Pete, I disagree with the idea that the pinion bearing could be loose, thereby causing the secondary condition. If that were the case, there would be major problems within the banjo, with failure long before the coupling pins sheared.

 

[ford38v8]

Henry, to answer your question regarding the preload, the preload is set on the pinion while nothing else is impeding the movement of the pinion. That means having the pinion and its bearings insgtalled in the banjo which is otherwise empty, no ring gear, no axles, no axle housings. There is a KRW tool, which is a spring loaded wrench with a gage, doesn't work well at all. Best to do the job the way the old time mechanics did it: Clamp the pinion in a bench vise pointed down, the banjo free to turn above the vise. To test the preload, hold the banjo with both hands, spin it hard and fast, and the banjo will come to a stop before it continues beyond one full turn after release. That will show you that the bearing has its correct preload.

 

[PeteVS]

Pete, I disagree with the idea that the pinion bearing could be loose, thereby causing the secondary condition. If that were the case, there would be major problems within the banjo, with failure long before the coupling pins sheared.

Back in post #42, Henry theorized that the pinion shaft might be moving up and down under or off load causing the condition that would kick up the fragments causing the noise. Whether the pinion shaft is moving up or down, or fore or aft, I feel that the pinion bearings should be set as you state. I wonder if there is any perceptible looseness in the pinion bearings, either sideways or axial? The fact that the noise occurs only under no load, to me, indicates that the pinion is loose. IMHO

 

[Old Henry]

Now you can see why I'm scared to death to do anything!!

 

[ford38v8]

Pete, I don't think so, because looseness would produce horrific results within the banjo. The cause of the noise, I believe, is the same cause that sheared the pins: Movement fore and aft. Correcting the cause of that movement should provide answers to all the questions of the universe for all time.

 

[Old Henry]

The lock washer slides onto the spline and cannot turn.

Once I realized that the lock washer could not turn I ruled out the thought I had that the nuts might have turned from the washer tabs being hit by the pin fragment. That just leaves play caused by wear.

I just went out and took the coupler off of the pinion spline and gave it a wiggle. It did have just barely perceptible play in it which I don't think it should have any. So, I'm probably going to tighten the inside nut to specs to take that out as I said before. Since I'm not going to have an empty banjo to spin I'll use an inch/pound torque wrench I'll borrow from Autozone to get it right.

Oops. Just realized I have no socket big enough and deep enough to put on that nut to use the torque wrench so I guess I'll just tighten it finger tight to "load" the bearings and that will have to be better than it is now with perceptible play. (That's what old Chuck would do and I like his thinking - sometimes.)

 

[ford38v8]

Henry, don't be discouraged! This stuff is not rocket science. I can see where different opinions can be confusing, but get yourself a copy of an old MoToRs Manual and read up on your project before you start. Get one of no later than a 1951 vintage 14th edition, and you'll have the best book you can find for any old Ford repair you can imagine. These can be had for less than $25 if you don't mind a few dogeared pages and greasy fingerprints.

 

[ford38v8]

Henry, the play you feel, if it is rotational play, is the relationship of the pinion to the ring gear, which is addressable by the use of proper thickness axle housing gaskets. If the play is not rotational, but up/down/sideways, you may be in the market for new bearings, particularly as you found metal in the banjo oil.

 

[Old Henry]

. . . read up on your project before you start.

Don't want no "project". Just want to fix what's broken and get back on the road. My hobby is more driving than tinkering.

 

[Old Henry]

Henry, the play you feel, if it is rotational play, is the relationship of the pinion to the ring gear, which is addressable by the use of proper thickness axle housing gaskets.

The play is not rotational. So, no problem with the gear fits. It's the other which I think will be taken care of by tightening the inside nut a bit.

. . . you may be in the market for new bearings.

Maybe someday when they actually break I'll fix 'em. Right now they're working fine so I'll just adjust 'em and run 'em.

Thanks for your interest and your help. I really do appreciate it.

 

[ford38v8]

The play is not rotational. So, no problem with the ring gear. It's the other which I think will be taken care of by tightening the inside nut a bit...)

Ok, then, but be sure you understand that to get a preload, you must actually turn the pinion, feeling the bearings load as you turn. To simply tighten until you feel no slack would spell disaster.

 

[Old Henry]

Ok, then, but be sure you understand that to get a preload, you must actually turn the pinion, feeling the bearings load as you turn. To simply tighten until you feel no slack would spell disaster.

10-4 good buddy. I'll turn as I tighten.

Thanks again.