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Front Axle

Rick

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Ok who wants to take this one on?Lets assume you just got a new axle in the mail.What are the steps you would take to install this axle so you can drive it out of the garage?
 
The first thing that I would do would be sure to mount the axle square and centered with the frame. I would then set the caster between 5 to 7 degrees negative (leaning toward the rear at the top of the kingpin). I would then set the toe in at no more than 1/8". With that basic set up, it should roll out of the garage just fine.
 
Now Total says no more than 5 degrees.Thats why i put that question up here.I'll add up all the answers and then divide by how many people post an answer then i'll have my answer.LOL
 
Mine is at 6 degrees also and handles beautifully. If you put too much caster in, it makes it a little harder to turn and too little tends to make the car want to wander. By that I mean that it is more difficult to maintain a straight line as you go down the road.

A good example of a lot of caster is a dragster. If you look at the front wheels as they try to turn, they lay way over, indicating the high degree of caster. But they set them up that way because they are built to go straight and the high caster setting helps a great deal.
 
I like 5 but any where from 5 to 7 is good.

Ron
 
NTBA write up on caster.
You adjust your caster by adjusting the length of the UPPER clevises on your radius rods. Typically, about 5 degrees of caster is plenty, and in some cases 2 or 3 degrees is all thats required. Have you ever pushed a shopping cart around a grocery store, and noticed sometimes the front wheels shimmy? Thats way too much caster! So go easy on your caster adjustment. Finally, there is camber... you can't change it easily because it's built into the king pin bosses. However, as your king pin bushings wear out, you induce more camber. So check your king pins & bushings occasionally for wear.

See he says 5 max 2to 3 in some cases?
 
Caster with a strait axle is all about feel and handling,there is really a lot of factors that make some things work or not.
5* to 7* is ball park,but here's just some factors;
Load on the front.
Rim off set.
Tire size.
Steering play.
Balance.
Shocks.
Tow.
Steering box.
Pitman arm (long or short).
Spindle arm(long or short vs size of pitman).
Steering wheel size.
Any way,these things and some others make rods def. so takes some fooling with on some to get the rite feel going for ya.
For the most part ,more caster [like 7*]will bring steering back to center better,but also adds to how much harder it is to turn[stiffer feel].
And 5* is EZ to steer,but will not find center as well.
 
Along with what "Bat" said, consider what kind of use your T will have. If you plan on doing a lot of touring, then the high end is what you want. That will cut down the fatigue factor considerably. If you are going to be driving around town mostly, then go for the low end. 5 degrees is a good compromise between the two.

Ron
 
Doncha just love the wonders of old style math?LOL
 
Drove the car for about 25 miles drove pretty good alittle drifting of the front end but about what can be expected from a 40 some year steering box and a king pin front end.i ended up with 7degrees untill i can have it done right.
 
Rick said:
Doncha just love the wonders of old style math?LOL

I'll take old math over new math any day of the week :D
 
Just about any place that sells tools with have an adjustable magnetic angle finder. Probably around $10 or so.

Ron
 
This thread provides some really good info. For me, I'm at a point where I'm locating my frame radius rod mounts, by threading the clevises and heims halfway into the radius rods.

Now should I leave my axle bosses at 90 degrees to the floor for this process or should I rotate the axle to introduce a 6 degree negative caster into the axle bosses in order to find the location of the hairpin frame mounts?

If the axle bosses are 90 degrees to the floor, can 6 degrees be attained all with clevis adjustments later?

It would be great to know the best way to go before I weld those brackets to the frame.
 
Satori speedway carries a caster adjustment guage online called the economy model for 31.99 their delux is 119.99. I cant find it in thier catalog but it is online. Francis
 
Craig, lay your axle on a flat surface with the king pin boss level and put bolts into the holes in the bat wings. You should find they have been welded on the axle with the degrees already dialed in.

Ron
 
all-world1 said:
...should I rotate the axle to introduce a 6 degree negative caster into the axle bosses in order to find the location of the hairpin frame mounts?
Yes.

all-world1 said:
If the axle bosses are 90 degrees to the floor, can 6 degrees be attained all with clevis adjustments later?

I would guess no. Only a few degrees adjustment total in the clevises.

You want no less than twice the diameter of the clevis shank engaged (aircraft standard) in the hairpin at final adjustment. I would set the caster where you want it with the axle before setting the clevises.
 

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