caster vs pinion angle

myota

my toyota
Location
south SL,UT
This is kind of a question that has been on my mind a little. So, I'll give a little background on what I know, if I'm wrong please correct me:
1. Caster and pinion angles are directly inverse related. pinion angle goes up, caster angle goes down.
2.It is more beneficial to have a high caster angle, except for those w/out power steering. Higher caster angle leads to more power needed to turn the wheels
3. Low caster angle leads to Death Wobble.
4. The best pinion angle is with the pinion pointing straight towards the drive shaft. Drive shaft angle = pinion angle


So, here's my question: When you lift a vehicle caster and pinion angle can get messed up, where do you put your pinion/caster angle??? Where is the best compromise with a stock housing?

My specific problem: I've got really bad death wobble and I want to get rid of it.
I'm currently running a stock '85 housing. I've got a spare '85/84 housing I can modify, but I don't have the tools or the time to cut and turn it now.
For you Toyota guys, what have you found to be the best caster angle? Looks like 5-7*
How have you modified your housing/suspension to get your caster angle?
What caster angle are you running now, and do you have any problems?
would you change your caster angle?


Reference:

Pirate 4x4, Toy secton
General alignment/tire information
 
Last edited:

DaveB

Long Jeep Fan
Location
Holladay, Utah
5-7 degrees is about right on caster angle. You don't want the pinion angle to be equal to the drive shaft angle, you need some operating angle on the ujoint in order for it to work properly. If you are running a normal driveshaft the pinion angle should equal the angle on the transfer case yoke. If you have a CV type driveshaft you point the pinion at the output of the tcase and come down 2 degrees.
 

rockreligious

NoEcoNaziAmmo
Location
Ephraim
I usually use an angle finder on the new axle before I pull it out of its original donor vehicle to get the factory pinion angle. that gives you the best caster position then I rotate it from there no more than 3 degrees (helps if your running High pinion stuff) any more than that and I would cut and turn the inner c's. kurts offer of $100 is the way to go. Ive seen people with too much caster come off of ledges with the wheels turned some and not be able to straighten them out without winching backwards...cheezy.
 

myota

my toyota
Location
south SL,UT
Thank you for the replies on how to rotate the knuckles on a housing.

Kurt, your offer does sound tempting...


However, my original question remains:
What have you been doing with a stock housing to deal with the caster vs. pinion angle problem?
 

stewmoney

Registered User
if you want a stock housing and a big lift there is no good way to put it eathere you get deth wable or your drive line will bind or a little of both. you choose.
 

cruiseroutfit

Cruizah!
Moderator
Vendor
Location
Sandy, Ut
...However, my original question remains:
What have you been doing with a stock housing to deal with the caster vs. pinion angle problem?

I think you have pretty much summed up the issue... there really isn't too much you can do. You can run some caster shims, and your pinion suffers, or you run the shims the opposite direction and your caster angle suffers. I've done rotations with as little as 3* and as much as 20*, while the upper ones may experience some pinion bearing oiling issues (none I have encountered), there is really no reason not to turn up your caster (Toyota designed them for 29" tires and manual steering ;)) and at the same time get your pinion up out of the rocks and preferable right up at your TC (assuming CV use)
 

rockreligious

NoEcoNaziAmmo
Location
Ephraim
thats what I was talking about, you can rotate it up 3 degrees without much notice on caster, and cut and turn inner C's all you want or untill your worried about the pinion bearings getting oil. Im running my front axle with 38's on a Jeep without CandT without any problems runs sweet down the hiway but its a high pinion. The $100 solution eliminates not only this discussion, but premature failure on all of your steering components, box and pump, and possible premature tire wear. not including safety issues.
 
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