Cut and Turning Of Axle's (1 Viewer)

[Ralphy]

Hey Guys & Girls

Just wondering if some one can fil me in on the whole idea of cutting the axle and turning it when going SOA, i've found plenty of pics of doing the conversion, and have just about everything worked out apart from the idea of turning the axle , im planning on using my current 2 " lifted springs , any ways any help would be appreciated

 

[FJ60]

unless your spring are really flat I think you will be too tall and tippy, most people use flat stock springs but I have seen a few HUGE 40's soa on lift springs.

The cut and turn is done to ease steep driveline angles caused by the SOA but many people here don't bother with it and run fine (hotly debated subject).

 

[woody]

The cutting and turning addresses two issues....pinion angle and steering caster.

Caster is the angle of the knuckle for steering...stock is +1 degree, meaning the upper trunion bearing is 1 degree back of the lower bearing. Larger tires, because of their longer footprint, run better with a higher caster number, as much a +6. To do this, you tip your pinion down 5 degrees more than stock to increase the caster...but...

this creates pinion problems, since the angle of the u-joints are often out of the operating range and either weak or binding on the yokes...you've effectively sharpened the angle at the pinion. So, the only option is to rotate this back up....but that kills your caster. Therefore, you cut at the knuckle, rotate the housing, and reweld. IIRC, mine was about 12 degrees rotation...some go as high as 15 degress. I then welded my perches to set my caster at about +4 and my pinion is now pointing more/less directly at the t-case. (because of this, you should run a CV-type front driveshaft, but I'm cheap....see http://www.4xshaft.com for info)

 

[Ralphy]

so the basics behind it all is to lessen the amgle of the drive train on the front , Im curious when you say a cv- type drive shaft , My current front shaft has 3 knuckle joins , 1 where it bolts to the transfer case and what looks like a double join on the bottom of the shaft , is what your refering to Woody to add extra flexability or for another purpose alltogether .
It's certanly something where you can read every article on the forum and tech centre about it but still have questions

 

[woody]

CV shaft is a double joint at the t-case and a single at the pinion...sounds like yer shaft might be installed backwards...

 

[ScottFJ40]

Would a trail only rig benefit from a cut N turn?

 

[Poser]

No, this is a spring over issue, that would be applicable to street or off road use...not just a trail only rig...Brian covered the reasons very well above.

Good luck!

-Steve

 

[woody]

trail benefits are driveshaft bind issues...road benefits AND trail benefits are the caster.

 

[Eskimo]

[quote author=woody link=board=12;threadid=12181;start=msg113011#msg113011 date=1078143689]
trail benefits are driveshaft bind issues...road benefits AND trail benefits are the caster.
[/quote]

Don't forget the added clearance under the pinion! I gained 6" of clearance under the u-joint on mine...