Front driveline angles on a lifted square

[chief_shotts]

I am curious what other square owners do to remedy harsh front driveline angles when lifting their truck.

My truck has a 6in lift, Dana 60, and np 205 tcase. The driveline angle is roughly 19 deg down, The t case is sitting at about 6 deg up, and the pinion is about 5.5deg down. Given these numbers the joint at my transfer case has an operating angle of 24.5 degrees.

Currently the front drive is unusable due to vibration from the driveshaft. Any advice from those who have a lifted truck would be appreciated.

 

[Edelbrock]

Does your front driveshaft have a CV joint on it?

 

[chief_shotts]

its a single cardan on both ends.

 

[Edelbrock]

I think you need something that is like in the pics shared. Should be cheap and easy to get. Standard equipment on a K5.

 

[CalSgt]

Transfer case flange pointed up 6 degrees and pinion snout pointed down 5.5 degrees would be about correct for a standard driveshaft with only one U joint at each end. The way you describe it sounds like your pinion and transfer case yokes are nearly parallel which is ideal. U Joints can handle a lot of angle if they are phased correctly, parallel. If the shaft is not phased it will induce a ton of vibration.

picture please

 

[chief_shotts]

Transfer case flange pointed up 6 degrees and pinion snout pointed down 5.5 degrees would be about correct for a standard driveshaft with only one U joint at each end. The way you describe it sounds like your pinion and transfer case yokes are nearly parallel which is ideal. U Joints can handle a lot of angle if they are phased correctly, parallel. If the shaft is not phased it will induce a ton of vibration.

picture please

I think i may have mistyped. Yes the transfer case is pointed up 6 degress and the pinion angle is at a 5.5 deg angle but in the other direction. the transfer case is not parellel with the pinion angle.

 

[chief_shotts]

I have noticed that the yokes are not in line on the driveshaft or out of phase and that the splines are cut in such a way that I cannot put it back in a phased orientation... so this could this be causing the intense vibration

 

[Ricko1966]

Yokes need to be in phase,and the pinion shaft and transfer case shaft have to be parallel, you got two things going against you.

 

[CalSgt]

I think i may have mistyped. Yes the transfer case is pointed up 6 degress and the pinion angle is at a 5.5 deg angle but in the other direction. the transfer case is not parellel with the pinion angle.

Sooo, the TC flange is pointed up (towards the floorboard) and the pinion snout is pointed up also? That’s all bad on single u joint shafts and could possibly be cured with a double cardan joint at the TC.

For a single joint driveshaft, The angle of the TC flange should be exact opposite of the pinion angle. One pointing up and the other down. If you imagine a laser beams coming from each those in the direction they are pointing, those lasers should be close to parallel.

However, on a double cardan you aren’t concerned with the angle of the TC, only that the pinion should point towards the TC.

Here’s a video that breaks down some of the science

xc_hide_links_from_guests_guests_error_hide_media

I have noticed that the yokes are not in line on the driveshaft or out of phase and that the splines are cut in such a way that I cannot put it back in a phased orientation... so this could this be causing the intense vibration

The fixed ear of the yoke at each end of the shaft should be lined up, also an issue

 

[Grit dog]

Sooo, the TC flange is pointed up (towards the floorboard) and the pinion snout is pointed up also? That’s all bad on single u joint shafts and could possibly be cured with a double cardan joint at the TC.

For a single joint driveshaft, The angle of the TC flange should be exact opposite of the pinion angle. One pointing up and the other down. If you imagine a laser beams coming from each those in the direction they are pointing, those lasers should be close to parallel.

However, on a double cardan you aren’t concerned with the angle of the TC, only that the pinion should point towards the TC.

Here’s a video that breaks down some of the science

xc_hide_links_from_guests_guests_error_hide_media

The fixed ear of the yoke at each end of the shaft should be lined up, also an issue

That’s a great explanation. I always knew angles needed to match without a double cardan joint but never really thought about the why.

 

[chief_shotts]

Sooo, the TC flange is pointed up (towards the floorboard) and the pinion snout is pointed up also? That’s all bad on single u joint shafts and could possibly be cured with a double cardan joint at the TC.

For a single joint driveshaft, The angle of the TC flange should be exact opposite of the pinion angle. One pointing up and the other down. If you imagine a laser beams coming from each those in the direction they are pointing, those lasers should be close to parallel.

However, on a double cardan you aren’t concerned with the angle of the TC, only that the pinion should point towards the TC.

Here’s a video that breaks down some of the science

xc_hide_links_from_guests_guests_error_hide_media

The fixed ear of the yoke at each end of the shaft should be lined up, also an issue

Thanks for the info

 

[idrivea2002golf]

The phase/alignment of the shaft is probably the best place to start. However, I had a similar issue in my Samurai. The short wheel base plus the ~8" lift (spring over and taller springs) I could NEVER get the front drive shaft to stop vibrating. Eventually I bit the bullet and order a double cardan joint and shims for the axle. Vibration is completely gone. I ordered mine from Tom Woods, but if the CUCV has one that's probably the easiest place to start.

1350 Series Double Cardan Drive Shaft

Custom made 1350 drive shaft. This is for those of you who have something more custom and need a 1350 double cardan shaft. For this to work you will have to have one of the options listed in each of the dropdown boxes below. Measure your flanges or yokes and the length as shown in the video...

4xshaft.com

 

[chief_shotts]

The phase/alignment of the shaft is probably the best place to start. However, I had a similar issue in my Samurai. The short wheel base plus the ~8" lift (spring over and taller springs) I could NEVER get the front drive shaft to stop vibrating. Eventually I bit the bullet and order a double cardan joint and shims for the axle. Vibration is completely gone. I ordered mine from Tom Woods, but if the CUCV has one that's probably the easiest place to start.

1350 Series Double Cardan Drive Shaft

Custom made 1350 drive shaft. This is for those of you who have something more custom and need a 1350 double cardan shaft. For this to work you will have to have one of the options listed in each of the dropdown boxes below. Measure your flanges or yokes and the length as shown in the video...

4xshaft.com

I called my local driveline shop and spoke with a tech there who’s got a similar setup in a jeep wagoneer. He suggested doing the same. Swapping in a 1350 double cardan. Out of curiousity what are the angles of your TC, driveline, and pinion? And how fast can you get going before experiencing vibrations on your set up?

 

[idrivea2002golf]

I can't recall the angles off the top of my head, i battled this battle about 2 years ago. In mine it was about 15-20 mph under acceleration. Samurai's have divorced transfer cases. The thing would dance around like no body's business.

It was really aggravating too. I live about 20 minutes from the foremost expert in Samurai's, Petroworks. I had the truck there probably 5-6 times trying to get the vibration solved. They swore up and down the angles were good and the drive shaft wasn't the issue (correct phase, new u-joints, angles measured within spec, etc.). So they rebuilt the intermediate shaft, I had them rebuild the transmission and transfer case (both were about 500$ and both needed it so money well spent). New clutch when I did the transmission. Lower range gears when I rebuilt the transfer case (the samurai's re-gear in the transfer case not at the pumpkins). Rebuilt rear axle, to have a locker installed. Inspected the third member of the front axle. Literally everything in the drive line except the front drive shaft. Double cardan and shims, problem solved.

In my case about the only time I noticed it was actually in 4wd. If I had the hubs locked but not engaged in the transfer case it was fine. If I had the hubs "free" but the transfer case engaged, fine. But 4wd and "locked" would be a problem. Since I have flanges I even removed the rear drive shaft just to eliminate the variable. It was definitely the front shaft.