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Kelvin R
03-02-2007, 01:16 PM
i am getting a drone from r r at highway speeds should i add or remove shims ?

Roscomacaw
03-02-2007, 02:04 PM
What does "rr" mean? Right Rear??? IF, for sure, you're getting noise from that side, I'd be worried about the wheel bearing on that end.
"Drone"? How about a failing tire???

If the rear axle is original OR was set up correctly the last time something was done to it, the shims shouldn't need adding or subtracting. They have nothing to do with the right side specifically - they're to establish end play in BOTH axles.[:I]

Miscreant adrift in
the BerStuda Triangle
http://images.andale.com/f2/115/106/906179/2006/12/7/truckonhill3.jpg

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe

Mike Van Veghten
03-02-2007, 02:46 PM
Input...need input! What's the car?

Has the car been lowered or raised?
Yea, that will cause a drone.

What's the car?????
If it has a two piece drive shaft, the center bearing support or bearing or u-joint itself may need help.

Mike

Kelvin R
03-02-2007, 03:40 PM
I have changed the complete rear-end housing and all in my 63 Lark Daytona from 62 Lark - I put same shims that were in donor car back in place. Drone seems to be coming from right rear. I am not sure of end play.

Roscomacaw
03-02-2007, 03:59 PM
Kelvin writes:"complete rear-end housing"

Does that mean you used the axles, innards and other stuff from the 63? In other words did you change the whole axle assembly or just mix and match parts as were needed? If the latter's the case, then just transferring the shims to match the housing has set you up for trouble.

If you swapped WHOLE AXLE UNITS, there should have been no need to mess with the shims unless you had to mess with the brake backing plates in the process. And, of course, that could have been necessary if one had no brakes or had different brakes or whatnot.

Miscreant adrift in
the BerStuda Triangle
http://images.andale.com/f2/115/106/906179/2006/12/7/truckonhill3.jpg

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe

Kelvin R
03-02-2007, 04:21 PM
I put in donor rear end from '62 Lark but kept original backing plates from my '63 Lark.

Kelvin R
03-02-2007, 04:36 PM
drone almost goes away when i take my foot off throttle

rusty nut garage
03-02-2007, 05:26 PM
You should have checked the axle end play per the shop manual when you swapped the rear end. You have a shop manual don't you?? If not that should be your first investment!
Your whine or drone as you call it is coming from the ring gear and pinion, either excessive wear or the ring gear/pinion gear runout is not set up correctly. You might get luck and have a loose pinion nut nut that holde the rear yoke on the pinion. Again the shop manual will be your best friend on this.
Good Luck
Russ

quote:Originally posted by Kelvin R

drone almost goes away when i take my foot off throttle


Russ Shop Foreman "Rusty Nut Garage"
57 SH (project)
60 Lark VIII 2dr sd (driver)

Roscomacaw
03-02-2007, 05:34 PM
So, did you ever hear this rear axle run in the '62?[?]

Miscreant adrift in
the BerStuda Triangle
http://images.andale.com/f2/115/106/906179/2006/12/7/truckonhill3.jpg

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe

Kelvin R
03-02-2007, 08:25 PM
I did not hear the rear end run before I changed it. I have a manual it says 1 to 6 thou end play not sure how to find that even with a dial indicater do I push and pull the axel by hand ?

John Kirchhoff
03-02-2007, 11:09 PM
I agree with Russ, it sure sounds (no pun intended) like the ring and pinion aren't aligned properly. Now that's a fun, time consuming job if there ever was one. The problem is you don't know if the noise started right before you got the axle or if it was that way from the factory. One of the trucks I drove at work had a howling differential when brand new and still sounded that way at 60,000 miles when it was traded off. If the noise is a recent development (as far as miles on the rear end goes) I'd be getting concerned but I don't want to frighten you into action when none is needed.

You may want to consider dropping the driveshaft in the rear and see if there's any end play in the pinion shaft and see how much backlash (freeplay) there is when you rotate the pinion one direction and then the other. Something else you could check would be to remove the cover and with a bright light, wipe off the oil and look at the surface condition of the teeth. I doubt you'll be able to see the pinion, but if you can see hard surface material flaking off the teeth or areas that appear worn and with a rough surface, it's down into the softer cast iron and the gears are shot. The teeth should be smooth and shiny, almost mirror shiny. If the hard surface material is still good, most likely you'll find a very shiny, elongated oval located in the center of the tooth. If this area is not centered, then most likely the thing has been apart before and someone didn't get it shimmed up correctly. That is if it was done a good many miles ago, otherwise it may not have had enough miles put on it to move the shiny spot. Again, rotate the gear and check for pitting on any of the teeth which would be the sign of one with very many miles on it. With differentials having many hours of very hard use, you'll commonly find the pitting. The cause is not just age, but the cast iron gear is softer than the hard surface material and the iron gives an extremely tiny bit. The hard surface material is more brittle and doesn't like to flex which is why it's usually not much more than .035". Too thick and it's too brittle. You can also press your finger on the tooth and slide it back and forth slowly (just don't turn anything because your howling will be much worse than the differential's!). I know it sounds dumb, but if you close your eyes you can feel things better and yes, it does work. You should be able to feel the shiny part and the low wear areas on the edge of the teeth that is just a bit rougher. If the center of the tooth feels rough, it'll eventually go south on you and I ain't talking about the car taking you to Florida for vacation. If you're concerned with it, I'd look for another rear end because the labor of getting someone to straighten it out would cost more than the axle.

KOOL R2
03-03-2007, 03:32 PM
Check your Pinion Angle per the shop manual. The front of the differential probably needs to be pointed down a bit more ( noise goes away on decelleration) . Shims are available at most spring shops. When you swap out axles even though they are from Studebaker to Studebaker the perches on the axle may differ depending on the car the axle comes from.
Peter Sant
KOOL R2

N8N
03-03-2007, 05:20 PM
Peter, I've heard that before, do you know what the difference in pinion angle if any is between pre-58 and 58-up passenger cars? I obviously need to set mine with an angle gauge but would like a rough idea what shims I may need to have on hand to "do it."

Also, since I can't fit under my car with all four wheels on the ground, is the bottom of the frame below the doors supposed to be roughly horizontal at a normal ride height?

thanks!

nate

--
55 Commander Starlight
http://members.cox.net/njnagel

John Kirchhoff
03-04-2007, 11:52 AM
Now here's something I'd forgotten but came to me in the middle of the night. I don't know if it was in a dream or I just woke up, but it's been so many decades since I did this it'd slipped my mind. It's a good way to determine if it's worn ring and pinion gears or just the pinion angle without tearing into stuff. This will work if you're good at backing up but if not you'd better leave it to someone who is. Back it up at speed and if it's the pinion angle, it should still make a noise, maybe just a bit less since axle torque will tend to bring the pinion end down just a bit. If it doesn't make noise, then it's most likely the ring and pinion. How so? When you're backing up, you're using the other side of the gear's teeth.

Now for those of you who are going to say the reverse axle torque when backing up will abrogate the exggerated driveline angle of deflection causing the present noise, come on now! If you can apply that much torque when backing up, you belong in the Joey Chitwood show where your supreme world class driving skills will make you some money!

KOOL R2
03-04-2007, 11:59 AM
Nate,
I dont know what the angle is supposed to be for early cars. The Avanti shop manual says about 4 1/2 to 5 degrees and it shows how to measure it in the book. I checked mine by measuring from the bottom of the frame to the floor then putting it on jack stands under the axles and adjusted until I got the same numbers front and back. Then I took the angle finder and came up with an adjustment of 3 degrees. Shims for three degrees are available at most spring shops.
I figured that the axle I installed which came out of a 1966 car had the perches on a little different than an Avanti would.

Peter

John Kirchhoff
03-04-2007, 07:54 PM
For any kind of shaft with two universal joints to run smoothly, both need to run at the same angle at both ends. That's why tractors have drawbars that slide forward and backward so you can even out that angle as much as possible. Since the angle of deflection on a car is going to vary to a greater extent on the differential than on the transmission, I figure you need to have the angle on the differential adjusted to the same angle as the transmission, preferabaly with the load the car will carry normally. Springs sag front and rear and motor mounts compress, all of which is going to change the angles. This is one case where I wouldn't go by the shop manual because when written, they weren't thinking about cars with 45-50 years of wear and age. I figure if the front has 3 degrees, that's want you want on the rear and if it has 5, that's what you want. The reason you want the angles fairly close is because as long as a universal joint is in a straight line, the driven shaft rotates at the same speed as the driving end. As you increase the angle of deflection, the driven end speeds up and slows down twice per revolution and the greater the angle, the greater the speed difference. Ag power take off shafts will normally operated at up to 45 degrees (much more that cars) and as long as you have two joints, the second joint will also speed up and slow down, except it cancels out the speed variation from the first one. That's why front wheel drive cars use constant velocity joints on the drive axles because the driven speed is constant regardless of the angle that results from turning the wheel.