Drive Line Alignment

[65 Plymouth Satellite 426]

In 1,000 Or Less Words Does Anyone Know The Correct Procedure For Making Sure The Rear-End--Driveshaft Alignment Is Correct Including Using The Alignment Tool And Shims To Help Keep Things Straight? I Heard That -1 Or -2 Were Good Numbers. We Are Hearing And Feeling A Vibration In The Car. Rear-End Was Just Overhauled Replacing The 741 Case With A 742 Case, All New Timken Bearings, Auburn Sure-Grip Unit, Motive Gear 3.55 Gears, Brand New Axles And Green Bearings, Super Stock Springs, Custom Engineering 3-Way Shocks, New U-Joints And A New Driveshaft. And Still...A Vibration! Driving Me Nuts! Help?

 

[lewtot184]

this is a good question. my 65 coronet has a driveline vibration at 55mph and i can't find a cure.

 

[snakeoil24]

What is your pinion angle with a loaded car?

 

[Powerflite]

When does the vibration occur? Vibration during deceleration or in neutral can be caused by not enough pinion angle (the pinion is angled towards the road). Whereas, too much pinion angle will cause vibration during acceleration - especially while going uphill, although you would likely hear it all the time as long as your foot is on the gas.

If you have vibration at all times and in neutral, then it is either not caused by pinion angle, or it could be that the offset (side to side angle) is off.

 

[Supershafts]

this is a good question. my 65 coronet has a driveline vibration at 55mph and i can't find a cure.

If you only have a vibration at 55 you don't have a pin angle issue.

 

[Supershafts]

In 1,000 Or Less Words Does Anyone Know The Correct Procedure For Making Sure The Rear-End--Driveshaft Alignment Is Correct Including Using The Alignment Tool And Shims To Help Keep Things Straight? I Heard That -1 Or -2 Were Good Numbers. We Are Hearing And Feeling A Vibration In The Car. Rear-End Was Just Overhauled Replacing The 741 Case With A 742 Case, All New Timken Bearings, Auburn Sure-Grip Unit, Motive Gear 3.55 Gears, Brand New Axles And Green Bearings, Super Stock Springs, Custom Engineering 3-Way Shocks, New U-Joints And A New Driveshaft. And Still...A Vibration! Driving Me Nuts! Help?

First there is no way you're going to get the right answer or fix this with "i have a vibration i feel in the car"

Im going to give you a list of questions i go thru with my customers and you need to give detailed answers.

1. when EXACTLY does the vibe start
2. does the vibe only happen under acceleration
3. does it only happen as specific speeds and what are they
4. was the shaft balanced (some shops are sketchy and skip that part)
5. when the vibe starts if you drop a gear or add a gear does it get worse, better or stay the same?

Lots of detail, im not able to drive it and the less you are able to convey the less i can help.

.

 

[Meep-Meep]

A drive shaft with the weld yokes in phase can only take one degree of misalignment. In other words, standing inside the tranny and looking through the tail shaft like a gun sight, you should have no side to side deviation when sighting in the pinion center (as mentioned above). So the procedure would be to adjust the elevation so that you have some misalignment in the vertical direction while keeping the yoke and tailshaft at the same angle. However, adding 5-7 deg nose down on the pinion is recommended for drag racing.

I had a vibration issue in my 68 RR with a Dana and I noticed I had a drive shaft that said in yellow junk yard pen "68 Firebird" (came with the Dana setup). Apparently this shaft is the perfect length for a 68-69 B body Plymouth with the Dana but the problem was the yokes were 15 degrees out of phase because the shaft on the 69 Camaro's and Firebird's must go up and over to get to the pinion.

 

[65 Plymouth Satellite 426]

Most Of The Vibration Noise Is Heard At 55 And Above. As Soon As You Get Off The Throttle (Coast Mode) You Hear It Very Clearly. Back On The Throttle It Smooths Out. Everything In The Driveline Has Been Replaced Except The 727 Which Had Some Minor Adjustments Made And New Tranny Fluid, Filter And Pan Gasket Replaced. Driveshaft Has Been Retubed, The Old One Had .030 Run Out On The Rear-End Side, .010 On The Middle And .011 On The Trans Side. Really Bad! I Do Notice Wheel Shake In My Hand While Driving. Could Something Upfront Be Out Of Wack Thats Vibrating ? Front End Alignment, Torsion Bars Or Idler/Pitman Arms, Tires? I'm Going To Send The Car To A Reputable Transmission Shop And Have The Pinion Angle Checked Thursday. Thanks For All Your Suggestions So Far! Going Nuts In York!

 

[Supershafts]

1. when EXACTLY does the vibe start
2. does the vibe only happen under acceleration
3. does it only happen as specific speeds and what are they
4. was the shaft balanced (some shops are sketchy and skip that part)
5. when the vibe starts if you drop a gear or add a gear does it get worse, better or stay the same?
6. when the vibe begins can you drive thru it? and what is the speed at when it is gone.

Lots of detail, im not able to drive it and the less you are able to convey the less i can help.

. Lets try those questions again...

This issue

I Do Notice Wheel Shake In My Hand While Driving.

that is not driveline related, the other stuff you're complaining about sounds as if the shaft wasn't balanced.

Your old shaft?
Why didn't they machine the weld and retrue the shaft and pull the .010 and .011 that .010 and .011 are nothing to pull and could have easily been balanced out.
But a new shaft upgraded from the dinosaur error is better, but if they retubed it which sounds odd since detroit constantly used swedge tube (other than the hemi cars) which would mean you now have a narrower tube thruout which is not a good thing and that may also be your vibe issue.
Measure the tube and let me know what it is, is it 2.25, 2.50 or 2.75, if it's a hemi car it should be 3.25

 

[65 Plymouth Satellite 426]

Supershafts:

Report Card Back On My 65 Plymouth With The Driveline Issues. Car Has Been In The Trans/Rear-End Shop For Three Days. So Far, They Have Found That The New Driveshaft That Was Retubed For Me Was 1-1/4" Inches Too Short In Length! What? No Wonder It Was Vibrating. Machine Shop Redid The Shaft Correctly And Returned It To The Rear-End Shop...At No Charge. Monday They Will Road Test And See How It Drives...They May Yet Pull Apart The Rear-End After Checking The Nose-Down Pinion Angle Alignment! Its A Slow Process.

 

[Supershafts]

OK the 1.25 issue would have been a problem if the car had a wicked vibration and got worse.
I also find it odd that it was 1.25" short since the shop would have cut the new tube to the weld to weld length and then machined out the weld yokes (also odd) and re-used them in the new drive tube that was cut to that length.

If the shaft was to short it would have started to whip as it went faster.
Many of the mopar shafts detroit made used extremely long slip yokes and they can be set much differently than other shaft, so if it had a 9" long slip and 3.5 inches were out that wouldn't be anything to worry about.
If the slip yoke had enough engagement in the tail bushing it was fine.
UNLESS the shop performing the work made the age old blunder of measurement with suspension at full droop, then that would explain the 1.25" too short issue. I have had many shops do this because the shaft was tight to remove with the suspension hanging they would send the shaft say remove an inch and then find out they just bought the customer a new shaft (most mopars, actually all can't be re-tubed without making bushings or machining the weld yokes which i don't bother with and give the customer the old shaft)


You said earlier it had a issue when you got off the gas and when you got back on the gas it lessened, that is not what a shaft feels like that is to short and not engaging the bushing correctly.
I suspect the issue is in the balancing or lack thereof

 

[65 Plymouth Satellite 426]

The Shop Said As Of Friday, The Issue Of The Drive Line Angle Has Not Been Addressed. More To Come I'm Sure!

 

[Supershafts]

Something isn't right there, this isn't a 2 day fix

What shop, i see youre in PA, bring your car to Bill Rielly Ph- 570-443-7440

 

[65 Plymouth Satellite 426]

The Shop Has A Very Reputable Record Of Doing Very Good Transmission And Rear-End Work. His Work Load Is Stacked Up A Month In Advance, Therefore He Never Tells You He Is Too Busy. He Works You In! My Project Is Just Taking More Time! Name Of The Business Is A1 Transmissions, Dallastown, PA. Bill Is Located A Good Distance From Me And Normally Works On Mopar Suspensions.

 

[Supershafts]

Something isn't right, you don't move to the next job until one is finished, and you don't have a 180 mph vibration issue that would take either a very late after hours need to find that vibration or a track rental.

I am trying to 1. understand why they played with the length of the shaft
2. what you had that caused them to play with the shaft
3. you never stated the cars original shaft had a problem, and why after changing spings and diff did it make a issue.

Now 3. i can understand the need for balancing the shaft, since whenever you change joints you are taking a 70/30 chance the shaft is going to need to be rebalanced.
If the gear ratio was the same then the shaft is not being put thru a new rpm, so then that leaves the shop that built the shaft never balanced it or isn't able to.
Which is where i see this problem since the housing wasn't changed only the center so that angle hasn't changed.
.

 

[65 Plymouth Satellite 426]

Supershafts:

Got The '65 Back Today And Most Of The Vibration Noise Is Gone! They Placed 6 " Shims In The Car, Lengthened The Driveshaft, Repaced The Perch Centerpins And Now The Pinion Angle is Sitting At -5 Degrees! I Think That I Read Somwhere That The Maximum Pinion Angle Should Not Exceed 2-1/2 -3 Degrees! I'm I Right On That?

 

[Supershafts]

Yes, if the shaft may exceed 5000 rpms then 5 degrees would be something you want to decrease to 3 or less. Now 5 degrees would be the operating angle, if they have the pin set at 5 degrees and the shaft is at say 9 then under load it'll be near 0 or 1 (depending which suspension) and then the 5 degree angle will be fine

 

[65 Plymouth Satellite 426]

Ok..Thanks For All Your Help! Appreciate It!

 

[Supershafts]

Hopefully all the issues are gone now