Driveline vibes.

greenmachine99 · 08-24-2005, 07:32 PM

I put on a CV shaft and dialed it in tonight. I made pinion agnle the same as the driveshaft. 18 degrees, but i still get vibes at around 60 and up. Usaully under acceleration but some just from moving. Should i keep it were it is since it is the same angle, or adjust it until i dont get vibes? If so which way? Or could it just be the lugs on the mtr's causing this vibe?

Mudinyeri · 08-24-2005, 08:32 PM

Gee, another vibration question. These have to be the most popular on the site.

Well, ideally, your pinion angle (input angle) would be 1° less than your DS angle. Usually, though, you would notice that at launch and not at 60 MPH.

If the vibe occurs at 60 and remains when you let off the gas, I'd be willing to bet it's not DS related. Yes, your DS will continue to spin but at a different rate - gradually slower when you let off the gas.

Did you change tires at the same time you put on the DC DS or where you running these tires before?

Why did you put on the DC DS? Were you experiencing vibes before?

What does the vibe feel/sound like? Is is constant or does come and go at some frequency?

Man, I hate vibrations!

tcourdin · 08-24-2005, 08:37 PM

I had the same problem with my YJ. Had too big of degree of shim under the axle. Put less in and cleared right up. Good luck.

skates04 · 08-25-2005, 12:45 AM

I had the same problem just installed new SYE and drive shaft, still had the same vibes, Checked, and re did my angles like 10 times, finally pulled my front drive shaft, and no more vibes, just took in the drive shaft and it was out of balance.
So pull your front drive shaft and see if they go away

AjRagno · 08-25-2005, 01:56 AM

I had a problem setting mine too. I tried everything form -2 degrees to 0. It would always end up vibrating within 50 miles or so. I got it set correctly at -1 degree and 2 gallons of fuel left in the tank. The fastest I've gone since is 70MPH, but I haven't had anymore vibes.

Best place to measure pinion angle is on the side of the differential. Adjust it, then measure the angle of the drive shaft. As you raise or lower the pinion, the drive shaft angle also changes so you need to go back and forth, measuring the driveshaft and pinion angles.

greenmachine99 · 08-25-2005, 06:36 PM

Just took off the rear DS and took it to 65, no vibes at all. Its definitly rear driveline, my pinion angle is right on should i make it 1-2 degrees lower?

UCTJ · 08-25-2005, 06:52 PM

Greenmachine.....I am having the exact same problem. When I get up to 60 and more I get vibes....so what did you finally set your angle at? I have a SYE w/dbl cardan d/shaft....its at about 15-17 degrees......whats yours at now???????

greenmachine99 · 08-25-2005, 09:01 PM

19 degrees.

greenmachine99 · 08-30-2005, 06:55 PM

I still get vibes under acceleration, that means i need less pinion angle right?

otisdog · 08-30-2005, 07:00 PM

Drop the pinion down a hair and try it.
Another thing you can try is flip the driveshaft 180* on the pinion yoke just in case it's a balance problem
jim

Mudinyeri · 09-01-2005, 03:57 PM

Quote:

Originally Posted by greenmachine99

I still get vibes under acceleration, that means i need less pinion angle right?

Your pinion should be about 1° less than your DS. In your case, try adjusting your pinion angle to 17°.