Pinion angle question
#2
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Join Date: Aug 2005
Location: Tell City, IN
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Has to be done with the rearend to adjust Pinion angle. Pinion angle in itself is a direct relationship with the Pinion Gear since the yoke is attached to it. The driveline angle would be effected if you put a shim under the trans mount. What kind of setup are you running?
#4
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Join Date: Feb 2006
Location: VA Hospital, Dallas, Tx (214 302 1924) cell-972-464-7400
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Roadrunner,
Are there not any threaded adjusters on the rear of your ladder bars? I do not know of any that can not be adjusted some for pinion angle adjusting?
Before you fight with adjusting the angles, just what is your current pinion angle in relation to you driveshaft angle? Does the driveshaft angle up as it goes forward from the rear yoke and U-joints?
Also do you have leaf springs or something different?
Ed
Are there not any threaded adjusters on the rear of your ladder bars? I do not know of any that can not be adjusted some for pinion angle adjusting?
Before you fight with adjusting the angles, just what is your current pinion angle in relation to you driveshaft angle? Does the driveshaft angle up as it goes forward from the rear yoke and U-joints?
Also do you have leaf springs or something different?
Ed
#5
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Join Date: Aug 2006
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I just spent tonight lowering front of ladder bars. Before i had zero angle on very back of driveshaft. Now it looks like i have 2 degrees of angle just moving bars on hole down. I have adjustable shocks in regards of question. Is this enough angle? I cant tell until morning when i start car and drive it to see if vibs are gone. But zero angle is not good, i know that much, hopefully no more twisted driveshafts for me.
#6
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Location: Tell City, IN
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I run a ladder bar setup with coilovers and run 1.5 degrees of Positive pinion angle to get my driveline angle right. If you have Leaf springs then more negetive is required to keep it at or around 0 under load.
With the ladder bars and Coil Overs the rear suspension don't move much.
With the ladder bars and Coil Overs the rear suspension don't move much.
#7
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Join Date: Aug 2006
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Thats my set up also! I have five holes on front of bars, it was up on top holes and zero angle. Last night i moved them down a hole and got 2 degrees of angle. Still have yet to run car this morning to see if vibs are gone. Hopefully sway bar doesnt need to be adjusted moving everything last night.
#9
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Join Date: Mar 2006
Location: Illinois
Posts: 96
The solid mount on the tranny could be your vibration problem. Not so much problem as transmitting what vibration you have. I like solid engine mounts but trannys should have some give.
2 to 5 degrees is good threw the movement of the rear, but if you moved the front of the ladder bar, you have changed your instant center. If you adjust on the rear of the bars, it will keep the same I/C if you adjust both the same.
When looking for a vibration, I jack rear up and first check for loose u joint or sloppy tail shaft or pinion bearing. Then remove wheels and tires, if you have drums a couple washers and the nuts back on and run it. Still have it, get a chalk or grease pencil tape it to a yard stick and prop it on a short jack stand and move it slowly towards the drive shaft, front and back. This will give you a rough idea where it is. Don't forget a bent or twisted axle can do this too.
2 to 5 degrees is good threw the movement of the rear, but if you moved the front of the ladder bar, you have changed your instant center. If you adjust on the rear of the bars, it will keep the same I/C if you adjust both the same.
When looking for a vibration, I jack rear up and first check for loose u joint or sloppy tail shaft or pinion bearing. Then remove wheels and tires, if you have drums a couple washers and the nuts back on and run it. Still have it, get a chalk or grease pencil tape it to a yard stick and prop it on a short jack stand and move it slowly towards the drive shaft, front and back. This will give you a rough idea where it is. Don't forget a bent or twisted axle can do this too.