SOA perch Question (1 Viewer)

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Oct 26, 2007
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Idaho
First SOA on fj60, I had the front axle cut and turned 8 deg., giving me a 13 deg. Pinion and 5 deg. Castor.
I have read a lot of threads that claim you need to place the entire weight of the vehicle on the axle prior to setting angles and welding perches. Is this really necessary? What if anything is going to change in regard to welding perches at 0 deg.? My feeble little brain tells me that setting the angles on the bench and welding the perches would obviously be easier and can’t see what the vehicle weight is going to change. There must be something I’m overlooking. Any feedback would be great, I plan on welding perches ASAP.
 

Cruiserdrew

On the way there
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Mar 15, 2003
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The issue is that there may be variation in the angle of the spring arch, that throws off the calculations. If you set it on the springs, set the pinion angle, then cut and turn the knuckles to give the proper caster, then you know everything is going to be right. Besides, just tack the perches, then pull it out and finish welding on the bench. That's what I did.
 
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So basically I will just work with what I have, based on the cut and turn I have. Looks like I may not get the angles I was shooting for.
 

Tapage

Club 4X4 Panamá
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you could always adjust your angles with your perch mounts to a certain degree. But yes, there is no set formula, every truck is different.

Due to your spring desing and front Cruiser weight ..

Usually 8º should be enought .. but again it all depends ..
 
Joined
Oct 26, 2007
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Still definitely in the learning stage but based on a lot of advice from those that had SOA experince, 8 deg. was the number based on using original (flatter OEM) springs. The problem I’m up against is my front diff. side perch is a Ruff-stuff two piece setup that looks like it needs to be welded in place prior to putting the weight of the vehicle on it.
 
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Oct 26, 2007
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Using Dan’s (RUFFSTUFF) two piece perch has anyone had trouble getting the diff. back in? Mine is currently at CBI being re-geared. I’m thinking I should wait to weld looking at how close it may be.
Anybody used this and had trouble getting diff. in or out?
 
Joined
Jan 2, 2003
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Park City, Utah
Yes it is absolutely necessary in my opinion. Case in point, your pinion angle seems way high to me. You do not want to ball park it based on what you think it will sag. I have made this mistake myself before and eventualy corrected it, measure twice, cut (and weld) once.
 

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