jkJason

Ok I know this has been beaten to death but after talking to some shop owners they think I will have problems with driveline vibrations with as little as 3 degrees of castor, they want to bring the pinion up more for the aftermarket shaft. How are some of you running up to 7 degrees without issues? Do you just deal with the vibs as a trade off for nicer handling? I think WOL cracked his t-case from vibs right? i've got mine at 3 degrees with no shaft right now. I hate how it handles so I'm gonna move it out to 4 or 5 degrees tonight but am concerned when I put the shaft in it will cause problems.

BaltChief

I'm a gonna watch this one.....my shaft is gonne need to be replaced soon...

MPBoxer

Don't our jeeps come stock with like 4.2 degrees of caster? I don't understand how 4 or 5 would be detrimental.

bostonMA

In 2 wheel drive, the pinion is spinning the drive shaft rather than the transfer case. I don’t have a problem in the front, even though the CV and pinion is far from parallel with the shaft, because there is little force on it when it is 2wd.

I don't use 4wd over 55 mph and this seems to work.

I believe that there are vibrations but there is not enough force on the shaft to make the vibration noticeable.

You should be fine bringing it to stock spec. Also, I noticed a huge improvement in high speed handling with the caster in spec.

bigbluejk

bostonMA has good info. It will also help if you use a yoke style driveshaft and not a cv driveshaft that bolts ub like OEM did. ya know what I am talking about? Like the Reels OEM replacement shaft. It puts the cv a ways out from the transfer case and can cause vibes I think.

What type of driveshaft are you planning on running?

edwin907

I've got like 7.1 degrees of caster running 35" Toyos.
Whether this is an accurate number I can't tell you but it is the number of degrees read by a digital level on both knuckles with the digital level set parallel to the rim.
I have arrived at this front end setting by shortening the FT upper arms about 1/8" from stock, and lengthening the FT lower arms somewhere over 1/4". This method gives good caster while retaining maximum clearance between the trackbar and the differential cover. With my FT front trackbar, it's close to my ARB cover, but it's never hit. But it is close, damn close.

My front factory driveshaft (or maybe one of the flanges) was never particularly smooth. How do I know, 'cause when I installed the JE Reel 1310HD/yokes it was way smoother. I fully expected to have to make some adjustment, but never have.
I get a slight, and I mean very slight, rythmic vibration at roughly 57-63 mph which is just barely noticeable, and may not even be the driveshaft. An excellent experienced 4WD mechanic said he didn't feel a thing.

When I ordered my driveshafts from David at Northridge you had to call to order a 1350 rear with the 1310HD front the way the website is set up. I told him I wanted the smoothest possible front setup and he agreed with me that the 1310HD with yokes at the transfer case and pinion would be potentially smoothest. He said some Jeeps do well with 6 or more degrees, and some have to be around 5 to keep driveshaft vibrations in line but you do want more caster with increasing tire size.
And no, I'm not concerned with vibrations in 4-HI at 60mph, but given the pinion angle, it'd have to vibrate under power, wouldn't it?

jkJason

For a little more background info I'm sitting at around 4 inches of lift on a 2-door. I've got the rear pinion angle set up inline with the t-case so thats no problem. I've been collecting as much info from shop owners and they all believe how my front is set now (at 3 degrees castor) is already pushing it for the pinion. Teraflex recommends running 3-3.5 degrees for my lift. Thats why I'm wondering how people are running up to 7 degrees. Also, I'm not driving at high speeds in 4wd, but I know that in 2wd the front ds is still spinning. Does this not matter cause there's no power going to it? At 7 degrees it seems like the pinion will actually be pointing down to the ground..which seems bad but if it's not causing problems then I guess its ok? Sorry for the length of reply's I'm just getting alot of mixed info from here and from shops.

jkJason

Yes but when you lift the vehicle the angles of the driveshaft to the diff and t-case increase and at 4'' of lift this can start inducing vibrations if the pinion angle isn't corrected, I believe.

jkJason

Hey man, after doing my research I ended up going with Tatton front and rears, 1310 u-joints. They seem to be of excellent quality with a lifetime warranty.They came with new flanges front and rear for both the diff and t-case. I've got the rear installed with no problems and I have the front flanges installed but not the shaft, waiting to decide what to do about my pinion/castor angle first.

Piginajeep

Who's running stock Driveshafts and who's running aftermarket.


the stock shafts will damn near take any angle and wont viberate. After markets not so much.


I'm running about 7 degree's. I dont count as I have the Spyntec hub kit. So my front doesnt spin.