Rear End Noise

chap52

chap52

Well-known member
I have a 52, F-1, 239, 3sp. I just completed an engine rebuild. I pulled the engine and transmission for the project. Replaced the rear engine mount and put it all back together. All running well. That's the good news.
During the three month project I also replaced the front seal in the stock rear end. Now I have what sounds like a granny gear rear end drone noise as I roll down the street. I realize that it's pretty low geared anyway but this noise seems greatly intensified since the rebuild. I am not sure that having an engine without all the noise it use to make (sounds "sweet" now with the new cam & dual 94's) has just made the low groan more noticeable or if I got something out of alignment?
Any thoughts?
 
No offense taken...Yep, checked it twice...Was going to check it again when I get home this afternoon. I was even planning on draining/ refilling it just to be sure. That would be a sweet fix!
 
All I did in replacing the seal was drop the driveline, remove the yoke, removed the old seal and I believe there was a washer also, replaced it all.
 
When you removed the yoke did you count the turns coming out and turn it the same amount going in ? That should put the pinion back where it was as far as preload and gear alinement. JMHO.
 
I have never taken one apart so I can't help you there do you have a manual is the gear oil the right weight?
 
Yes I have a manual...gear oil 85-145. I don't understand how just changing a seal could cause this issue? I didn't open it up or touch any of the inners.
Appreciate the input.
 
How did you tighten the pinion nut?

Does your rear have a crush sleeve? or not?

If it has the crush sleeve, it needs to be replaced to keep the preload on the bearings, I'm a bit lazy (but never had an issues) as I use an impact wrench to snug them back down (with crush sleeve) when just replacing the seal, I take more time when setting one up and try to torque to spec.

I'm gonna guess you used a 1/2 breaker bar, put it in gear/set the brake/etc...and tried to "snap" tighten the nut, if so, you're probably a good 100 ft/lbs shy of spec (I think somewhere around 220-240?)...but for sure if you have a crush sleeve, get a new one and start over.
 
As mentioned, preload on the pinion bearings for sure. Used bearings should have a lighter preload than new but it has to have that preload or the pinion will not stay in it's normal place of operation. The Dana 44 usually uses shims on the spacer. You might have to remove or substitue shims to reduce the spacer distance enough to get the preload back. Torque to turn on new bearings is 8 to 12 inch/pounds rolling torque (disreguard break away torque).
 
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I am scratching my head trying to understand your input. So it's all about the nut on the u-joint yoke and the washers (spacer) behind the seal??? Ive never dealt with one of these, please tip tow me through this.
Thanks
 
chap52 said:
Yes I have a manual...gear oil 85-145. I don't understand how just changing a seal could cause this issue? I didn't open it up or touch any of the inners.
Appreciate the input.
Click to expand...

In Layman terms:::: The nut sets the interferance of the pinion & ring gear.
If wrong shims are installed it will change the setting of pinion & ring gear.
I don't see you saying you changed any shims,so the next thing is you have not put the nut back in the exact spot it was before the seal change.
If too loose the pinion is now set to deep in the ring gear, if the nut is to tight the pinion is not deep enough in the ring gear.
My Guess is that it is not tight enough allowing the pinion deeper in the ring gear giving you a hollowing sound.
Taken to the extreme looseness you should a clatter when you back off the gas.
 
Thanks, that makes sense. I am a product of the Los Angeles City school system of the 50's-60's. Keeping it simple is sometimes is still way over my head...
Appreciate the input.
 
Keep asking Questions, MOST every one on here are willing to talk you through it.
Those that get there feathers ruffled you dont want there input any way.
This site gets better with every Question asked & answered,
There is the search section that you can ask you question from but some times the termanolgy is different so it may not show up ( EXAMPLE::: what we call a hood the English call a Bonnett / Gasoline = Petro & so on )
So if you dont understand ask again your Questions may help Someone else also.
 
Thanks Bill,
Appreciate the support and encouragement from you and others on this site. As a kid (way back) you learned by "guesstimating" and input from peers that "seemed to know" how. It's a real blessing to have a group of "busted knuckled" people out there willing to share the knowledge they have attained over the years. That's called "traditions" and so much of that has been lost along the way.
To all the "givers" on this site, Thanks and have a Blessed Holiday Season.
 
Most of the rear axles I have messed with over the years have Timken tapered roller bearing cups & cones for the input pinion shaft. The tapered bearing sets appose each other just like the front wheel bearing sets on most of the older cars & trucks. On those you set the drag by feel as you torque up the nut but on a rear axle assembly, it needed something that could last at least as long and the bearings do.

You may not have gotten it torqued up snug enough or wear on the cone sets have decreased the preload. You don't want to twist the pinion threads off but you have to reach the specified torque which can be a bit harder when you can't lock the shaft from turning. One suggestion was using an impact wrench. The only drawback with that is that you won't know what the final torque is. You should have no in and out play or side to side shake at ALL! The preload eliminates that but still allows the shaft to turn freely with only a bit of drag. New bearing drag torque is only 8 to 12 inch/pounds so I would shoot for around 5 to 8 in/lbs for the used bearing sets.
 
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