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Ron Dame
01-24-2007, 08:44 PM
Ever since I put the overdrive transmission in my truck, I've had a vibration at speed.
Sure I'm slow, but I finally figured out the pinion angle is way diffrent than the
transmission angle. I thought there were shims to put between the spring perch and the
spring to change the pinion angle, but no one here knows about such an animal.
So how do I get the trans and the pinion shafts to be parallel?

Ron Dame
'63 Champ

Ron Dame
01-24-2007, 08:52 PM
I thought all trucks were one piece...it's a '63 champ...long tailshaft



quote:Originally posted by Dwain G.

Do you have a one-piece driveshaft or a two-piece? What transmission did you use, short tail shaft or long?


Dwain G.
(We're not called 'hillbillies' any more....we're now Ozark Americans)!


Ron Dame
'63 Champ

Ron Dame
01-24-2007, 08:53 PM
Thanks. I looked under driveline stuff, and did not see them.



quote:Originally posted by Alan

Summit Racing Equipment. SUM-770025 wedge plates in 2 deg. increments $19.95 per pair. (1-800-230-3030).


Ron Dame
'63 Champ

Dwain G.
01-24-2007, 08:58 PM
Do you have a one-piece driveshaft or a two-piece? What transmission did you use, short tail shaft or long?


Dwain G.
(We're not called 'hillbillies' any more....we're now Ozark Americans)!

Alan
01-24-2007, 09:26 PM
Summit Racing Equipment. SUM-770025 wedge plates in 2 deg. increments $19.95 per pair. (1-800-230-3030).

bigaadams
01-25-2007, 12:41 PM
The OD would at best only extend your angle..not change it..the phase is not altered. Is the driveshaft offset on the rear pad in comparison to the original transmission. Phasing the driveline is the work of three parrallel lines. First is the imaginary line of the angle of the pinion to the angle of the tailshaft...second is the inaginary line of the transmission in regard to the pinion input as it would continue to the rear. Third is the drivshaft itself and of course this could not have been changed by you as it would require cutting the tube. This will assume is correct. The parallel lines can be offset top to bottom, left to right and a combination of both..key is keeping them parallel and most articles say within 5 degrees..this is argued between builders..so I stay out of this..I am thinking 2 degress is the max fudge from the factory.

The vibration could very well be the drivshaft itself as in a lot of cases you can rotate it's mounting position till vibration is gone. Sounds funky but I have seen this correct vibration in many cases. On older cars it is my recommendation that if you remove the shaft..mark it for positioning back to original state.

If you do decide to mess with the angle of the pinion, you need to determine with a gauge what angle your tail shaft is and also the pinion angle. Wedges are available to correct angle..direction of insertion can change from a negative to a positive angle.

I would recommend that you start by determining the centerline of your car's chassis..this can be don with a tape measure and plumb bob to a marking on the floor. Pop a chalk line to highlight your cneterline. Establish you rear gear inaginary line also with the plumb bob to the floor..as the pinion is enclosed determining this may be a bit of a challenge..next do the transmission center line the same way. Chances are your tranny center to frame and rear gear center to frame is offset..no big deal..lot of cars have a 3 in or so offset...KEY is keeping it parallel. The tranny will be higher than the rear gear as the rear gear will move based on vehicle weight and road condition/shock quality. This is again best determined by the angle gauge.

It is not hard to find articles online by search on driveshaft phasing. Chances are they can explain it better than I...Hope this may help you...

N8N
01-25-2007, 07:08 PM
I got some from Jerry Forrester although I'm sure Summit and Jeg's sell them. I still have 'em but don't want to sell until I'm sure I don't need them (I now should probably do exactly what you're doing to my '55 now that I have the 4-speed in it)

nate

--
55 Commander Starlight
http://home.comcast.net/~njnagel

Ron Dame
01-25-2007, 07:19 PM
Thanks. To be clear, I changed it from a non- OD to an OD trans. I had a drivetrain shop shorten the D-shaft and balance it. All else has been checked and/or replaced, including output bearings, pinion bearings, u-joints, wheels, tires, and all. The difference in the diff pinion angle and the trans is very obvious...I bet way more than 5 degrees. Some one long ago had suggested a temporary fix: tape a piece of refrgerator magnet material around the driveshaft at the rear U-joint. I forgot why they thought this would work but it did, and I forgot about my problem until recently, when the duct tape failed, and teh magent went away. Now it's time to fix it right.

Thanks!

Ron Dame
'63 Champ

bigaadams
01-25-2007, 07:40 PM
you wrote: I forgot why they thought this would work but it did, and I forgot about my problem until recently, when the duct tape failed, and teh magnet went away. Now it's time to fix it right.

If you had to tape a magnet as weight on the driveshaft and the vibration went away but returned when the magnet and tape fell off..this in itself says the shaft is out of balance.

there are some nice illustrations here at this URL..this is what I tried to explain earlier..

http://jniolon.clubfte.com/drivelinephasing/drivelinephasing.html

Ron Dame
01-25-2007, 08:55 PM
The magnet was wrapped all the way around, so it was even. It changed the harmonics, or maybe the fore-aft balance, but not the rotational balance.



If you had to tape a magnet as weight on the driveshaft and the vibration went away but returned when the magnet and tape fell off..this in itself says the shaft is out of balance.

there are some nice illustrations here at this URL..this is what I tried to explain earlier..

http://jniolon.clubfte.com/drivelinephasing/drivelinephasing.html
[/quote]

Ron Dame
'63 Champ

hank63
01-26-2007, 01:46 AM
There's an old "rule-of-thumb" - a uni-joint should have an angle
1 to 5. Less, and the needles might not rotate. More, and the service life is jeopardised. That's what we used for long trucks anyway.
/H