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Yes it is 1⁰ positive castor and 8⁰ upwards on the pinion flange. Tranny is a sm420
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Yes it is 1⁰ positive castor and 8⁰ upwards on the pinion flange. Tranny is a sm420
Wow I think that was a little more than 2 cents But very through I appreciate it. It not so much scaring me off I just want a done RIGHT finished product. Looks like I have my work cut out for me... I like the shackle set up you have there. Do you know by chance the length on center is?OK so i just want to help a little bit but I don't want to scare you off. This might seem like a lot but I'm going to give you my 0.02$ anyways:
I'm not sure what you plan to have your ride height set up at, but for best road manners you may choose to put your shackle through the frame to bring the truck down further.
Here's how I did mine:
View attachment 2345304
It is important for you to determine what you want your final ride height to be before making finalizing your front end geometry. One fot he reasons for this is that depending on your axles location on the spring it will either rotate forward or backwards during the suspensions travel.
If your axle is directly in the center of the spring it will not rotate however.
Once you get your ride height (with the vehicle loaded as it would be during normal driving) you can start to make these changes.
Another thing that is often overlooked is the front axle skew. The front axle skew has an influence on the cross-camber and also the cross-caster. The cross castor you don't have to worry about as much (most vehicles of this vintage rang ~0.2-0.5* additional castor on the passenger side to account for road crown) but the crass camber is important.
If your axle is in good shape the cross camber will be 0*. Now if you axle is skewed in the vehicle (IE front spring hanger is further forward on one side of the other) than what happens is you gain camber on one side, and lose it on the other side. An example would be an axle that is setup to have 0.5* of positive camber (bottom of the tire inboard of the top) such as many vehicles of the era were working with could have 0.0* on one side and 1.0* on the opposite side if the axle was skewed in the chassis. This is due to the steering axis inclination. On most live axle vehicles the steering axis inclination is between 9-15*. I believe most of this era Toyota axle is around 9.5* SAI.
Now I don't want to scare you off but if you really want to get that puppy dialed in you can take a few steps here before you get it all set in stone and make your life easier down the road.
If it were me i would do the following:
Get a Firestone lifetime alignment
Get the ride height of the truck figured out (with the weight on it).
Finish welding the front drivers side spring mount (since you don't have much room to move it around with the steering box).
Get the passenger side partially welded in a location that you cam best determine is the closest to square with the drivers side. Try to weld it in a place where you can cut the welds later without too much fuss. In the past I have used the front spring mount on the rear axle as a reference for this.
Try to get your spring perches heavily tacked up with 5-7* of castor angle at ride height.
Get it to an alignment shop somehow. (I'm not gonna tell you how)
Look at the sheets and see what your Camber/Castor is once the set the toe.
If your castor is between 5-7* finish welding the spring perches on the axle.
If your camber is close to +0.5* on both sides weld the passenger side front perch up.
Now one more thing that is commonly overlooked- The thrust angle. This can be influenced if your front axle is not centered in the vehicle left to right.
Now everything that I said above is assuming your frame is straight and your rear axle is in the original position.
Your front and rear axles can also be skewed if there is a large difference in ride height or spring length from side to side.
If you show me the printout I can help you get it dialed in.
Hope that's not too much,
Mike
OK just for you:
Looks like 5 3/8"
View attachment 2345373
And rear 7.0":
View attachment 2345374
I originally had shackles like yours in the front through the frame. The allow for a lot more droop because they rack and swivel independently (the sides of the shackle aren't fixed to each other) but the holes quickly get rounded and "wallowed" out and the whole setup gets really loose causing the front end to wander around a bit. Good for the RTI ramp, bad for over the road characteristics and longevity.
I found these shackles at a land cruiser bone yard, I'm not really sure where they came from. The are ridged and much better for my application.
Mike
Hey sorry for the delay, I will respond soon when I'm not running around!I'm thinking just cut and weld new perches and achieve a few more degrees on the caster angle.
View attachment 2422300
View attachment 2422305
View attachment 2422323
The castle nut was down to far and the cotter pin hole was clear above the nut. So I put it in there to take some space out.Whats with the washer on the drag link end ?
Cut them off and throw them in the trash quickly if you value your frame. I've seen one ripped apart in person from that style(friend's FJ40)
Yes it is a 40 axel. I haven't had the trunnions apart on this axel ill have a look at that first.This is a 40 series axle correct?
Not great news for me! ..but good to have the info. Thank you.The major ripping happened at the back side of the front brackets. I seem to recall cracks forming on one of the rear shackle hangers. This was roughly 20 years ago with the forward facing brackets.