new lift- extreme vibes at 10 mph

[Streetgliderx]

not to hijack, but im going to be doing a 4 inch lift this spring and is it possible i might have this problem? The point to be doing the 4 inch was no to mess with the drivetrain much, am i gonna need to move around the tcase or mess with the driveshafts? Thanks.

/hijackoff

i thought the same thing and 4" MEANS DRIVE LINE CHANGES. no way to avoid it. unless you like the log wagon ride. it is worth it but it wound up costing alot in the long run to get it RIGHT.

whats a cv shaft? and how do you mess with the pinion angle?

angle shims under the rear springs changes the pinion angle and a CV= constant velocity,.. same thing you have in the front shaft next to the t-case. I know its not a true constant velocity but its been called that as a common name its true name is double cardan joint

 

[AZ79K5Project]

Take a close look at this pic in the original post. It doesn't look like the U-Joint is seated in the cap. Is it just the angle or is there a space?

 

[4X4HIGH]

what would a rear cv shaft cost? I know everywhere is different, but just a ballpark figure would do. some say single cardan shaft and some say double cardan shaft, which is better?

Since you have a 208 t-case you're limited to using the CV slip shaft which isn't as good as doing a SYE with a CV shaft but i'm not aware of any SYE kits for the 208. At any rate you're probably looking around 600.00 or so for a quality CV slip shaft. Jesse at HAD (High Angle Driveline) sells them, give him a call.

 

[Dabba]

hmm i just realized im having a hard time figuring out how this works, pinion angle and driveshafts and such. Hard to imagine. Whats different between the stock shaft and the cv? Any good source of driveshaft mechanics?

 

[4X4HIGH]

hmm i just realized im having a hard time figuring out how this works, pinion angle and driveshafts and such. Hard to imagine. Whats different between the stock shaft and the cv? Any good source of driveshaft mechanics?

Your stock shaft only has one u-jopint on each end, a CV shaft has one u-joint on the axle end but two u-joints back to back on the t-case end with a special yoke that has whats called a ball seat kit or centering kit.

Here is a pic of a CV slip shaft from HAD.

 

[Copasetic]

Take a close look at this pic in the original post. It doesn't look like the U-Joint is seated in the cap. Is it just the angle or is there a space?


View attachment 59192

I thought that myself but since no one else had brought it up, I thought I might have been seeing things. Wouldn't hurt to change that u joint out to see if that's where a lot of your vibe problems is. And ditto on the TC spacers. I"ve heard too many people talk about the frames cracking. Get some solid stock to go where those factory spacers are to give more surface area but make sure you grind your stubs on the front shaft.

 

[ryoken]

hmm i just realized im having a hard time figuring out how this works, pinion angle and driveshafts and such. Hard to imagine. Whats different between the stock shaft and the cv? Any good source of driveshaft mechanics?

http://www.pirate4x4.com/tech/billavista/PR-shaft/index.html

 

[Dabba]

thanks, i still dont get how they fuction different, i guess ill have to see them both spinning to see. I just know im gonna be doing a 4 inch lift this spring and im gonna have to learn about this problem and how to correct it. Thanks.

Edit: Any source of driveshaft mechanics would be helpful. thanks!

/hijack off

 

[Streetgliderx]

CV drive shaft breaks the angles the u-joints are running on in HALF. wikipedia had a auto cad rendered 3d spinning drive shaft if you look up the cardan joint. remeber that the CV we speak of is not a TRUE CV its a double cardan u-joint

 

[Dabba]

ahh, thanks

 

[jor]

Whats different between the stock shaft and the cv?

Here's a few more photos of a CV (double Cardan) joint. This is the front drive shaft from my 87 Suburban.
jor

 

[Dabba]

alright, nother question. Ive seen this double cardan shaft. My front driveshafts a double. At least it looks just like that and im pretty sure my truck is stock. Though i guess it could be aftermarket? My freinds bronco has a single in the front and a double in the rear. This stock or aftermarket? Why is the front different from the rear in my blazer and his bronco? Thanks. I can see the joint in the middle allows for motion of the axle on bumps, how does a single do this because i dont see that sliding joint? Sorry im very newb

 

[Hogback Fabrication]

alright, nother question. Ive seen this double cardan shaft. My front driveshafts a double. At least it looks just like that and im pretty sure my truck is stock. Though i guess it could be aftermarket? My freinds bronco has a single in the front and a double in the rear. This stock or aftermarket? Why is the front different from the rear in my blazer and his bronco? Thanks. I can see the joint in the middle allows for motion of the axle on bumps, how does a single do this because i dont see that sliding joint? Sorry im very newb

Your Blazer likely had that double cardan joint in the front. Its also common for Broncos to have them in the rear (stock).

The joint in the middle does not allow for motion of the shaft during suspension travel. The splined portion of the shaft allows for that.

Again the two joints at one end are to reduce the operating angle of each joint and therefore reduce vibration.

 

[Dabba]

ahh, still makes me curious as to why my front is a double while my rear is only a single, and why its opposite on the broncos? Thanks for the info thus far. It is amazing how much one can learn on this site in such a short perioid haha.

 

[WJACKSON11X]

I took everyone's advice and raised my transfer case back to stock location. Im taking my driveshaft tomorrow to get it changed to a CV style shaft. Ill keep ya'll poated on the outcome. Thanks again for everyones input.

 

[Streetgliderx]

mine is in the shop now dor a CV shaft i'll pick it up in the morning. i actually don't have any real reason to move the t-case back up its dropped using some spacers i made that fit the frame real well not the little round stockers,.... now for my question is there any real benefit to moving it back? other than stock look?

 

[Hogback Fabrication]

now for my question is there any real benefit to moving it back? other than stock look?

Clearance and a better front driveshaft angle.

 

[Streetgliderx]

nuff said