Caster settin?
Elder User
Joined: Feb 2003
Posts: 760
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From: Boise, ID
Caster settin?
Do you mean the castor built into the diff yokes or alignment castor?
If you're talking about alignment, I can't say what factory specs are but in researching the subject I read that you want no less than +2* and no more than +8*. For what it's worth.......
If you're talking about alignment, I can't say what factory specs are but in researching the subject I read that you want no less than +2* and no more than +8*. For what it's worth.......
Street Queen to the extr3m3
Joined: Jan 2005
Posts: 4,554
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From: Lubbock, Texas
isnt that the same question as the op...
Agree with thread mining, but stuff that old had to use the search function!
Which is comforting!
Agree with thread mining, but stuff that old had to use the search function!
Which is comforting!
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Joined: Dec 2007
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From: Dickson, Tennessee
If you are using the radius arms from the 79, you should look at the angle of the arms.
At factory ride height the arms would be about level with the ground, and have about 6 deg. of castor. Now with every inch of lift on the factory coil spring/radius arm suspension you will loose 1.2 deg of castor. Now with that being said every inch you lower the radius arms down from the frame you will gain 1.8 deg. of castor. So for 6 inches of lift you get (start with 6 deg.) 6" X 1.2deg = 7.2 Now take the +6 -7.2 = -1.2 of castor, now use 6 deg. c-bushings you will be at +4.8 of castor. now lower the radius down 1 inch (= 1.8deg) 4.8 + 1.8 = 6.6 deg. and you will be close.
Hope this helps.
At factory ride height the arms would be about level with the ground, and have about 6 deg. of castor. Now with every inch of lift on the factory coil spring/radius arm suspension you will loose 1.2 deg of castor. Now with that being said every inch you lower the radius arms down from the frame you will gain 1.8 deg. of castor. So for 6 inches of lift you get (start with 6 deg.) 6" X 1.2deg = 7.2 Now take the +6 -7.2 = -1.2 of castor, now use 6 deg. c-bushings you will be at +4.8 of castor. now lower the radius down 1 inch (= 1.8deg) 4.8 + 1.8 = 6.6 deg. and you will be close.
Hope this helps.
Senior User
Joined: Oct 2004
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I welded a 77 4x4 front end on my 64. I took it to get it aligned and they told me that my caster was off and 77's had not adjustment. The truck wanders a bit going down the road. The shop told me that caster allows for the wheel to come back to center? I have replaced all of the steering components even the gear box. Does the caster come in the radius arms? I just bolted them up to the frame. Can I drop them down a bit to get the proper caster?
Thanks.
Jack
Thanks.
Jack
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From: raymond alberta
caster is measured on the flat top of the knuckle you want at least 2* + caster no more that 8* i believe ideal for these things is 4.5*-6.5*+ which means if you measure from the d/s knuckle it will be rotated clockwise (or backward) from 90*
proper caster will allow the wheels to return to center and it affects handling and pinion angle (the angle of the drive shaft in relation to the pinion angle of the diff)
by lowering your rad arm mounts you will gain + caster...you can also buy caster corrected "C" bushings that are between the rad arm and the wedges on the axle for instance 7* C bushings give you 7* of + caster...this is if you have a big lift but you can buy them in all sorts of different measures
caster does not change with lift, ideally you want your caster to be between 4.5*+ and 6.5*+ no matter what, when you lift the truck it will change the caster measure that is why for anything lifts 4" or higher you need rad arm drop brackets or other forms of caster adjustment
proper caster will allow the wheels to return to center and it affects handling and pinion angle (the angle of the drive shaft in relation to the pinion angle of the diff)
by lowering your rad arm mounts you will gain + caster...you can also buy caster corrected "C" bushings that are between the rad arm and the wedges on the axle for instance 7* C bushings give you 7* of + caster...this is if you have a big lift but you can buy them in all sorts of different measures
caster does not change with lift, ideally you want your caster to be between 4.5*+ and 6.5*+ no matter what, when you lift the truck it will change the caster measure that is why for anything lifts 4" or higher you need rad arm drop brackets or other forms of caster adjustment
Senior User
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Thanks for the reply. I talked to my alignment guy and he said right now my caster is 0 and should be +2 degrees. I just happen to have a set of 2degree bushings I bought 5 years ago when I did the modification so I am going to put them on this morning.
Jack
Jack
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