Front driveshaft driveline vibration....why??

H

HeavyMetal

NAXJA Forum User

Location

Fairfield, CT

• Mar 4, 2006

• #1

So ive had my 5" lift for about 6 months, and my tom woods CV shaft and sye for the rear and all that, and ive been vibe free and basically issue free the whole time. Then, i swap in my rear d44 in and regear both axles to 4.56, now we put the front stock driveshaft back in, and my jeep vibrates like crazy over 40 mph, we take the front driveshaft out and its smooth as butter. Why out of nowhere would my front driveshaft now cause vibration with no change to the front of the vehicle other than the regeared d30??

 

Last edited: Mar 4, 2006

xjaddiction

NAXJA Member #666

• Mar 4, 2006

• #2

You've increased the rotational speed of everything (axles, u-joints, t-case, etc.) by switching gear ratios. If you have an SYE in the rear, some will allow you to put your rear d-shaft in the front. This will tell you if the front d-shaft is out of balance. I sent a front DS from TW back to have them to rebalance after the same problem occurred. That cured it.

This may not even be a d-shaft issue. Check u-joints etc. That's one reason lock-out hubs are so great on a 4x4.

 

J

Jeffro600

NAXJA Forum User

Location

Cheyenne, Wy

• Mar 4, 2006

• #3

Let me guess....non adjustable upper and lower control arms???

 

H

HeavyMetal

NAXJA Forum User

Location

Fairfield, CT

• Mar 4, 2006

• #4

Jeffro600 said:

Let me guess....non adjustable upper and lower control arms???

Click to expand...

why would that make a difference? i havnt changed lift height

 

ECKSJAY

Water is dirty

Location

Covington, WA

• Mar 4, 2006

• #5

What's your caster angle?

 

T

tealcherokee

NAXJA Forum User

Location

CT

• Mar 4, 2006

• #6

incorect caster and pinion angle, and the now faster rotational speed makes the vibes. also going to a larger diameter driveshaft will help

you have to remember, your driveshaft is now spinning about 1000 rpm faster than it was before....

 

J

Jeffro600

NAXJA Forum User

Location

Cheyenne, Wy

• Mar 4, 2006

• #7

HeavyMetal said:

why would that make a difference? i havnt changed lift height

Click to expand...

The two above posts is why....and is exactly the situation im facing...Swaped in axles with 4.88s with the incorrect pinion angles and i get TONS of vibes with the front drive shaft in place. With the 3.07s, it was not nearly as noticeable. Take it off and it drives as smooth as could be. Fixed control arms SUCK!!!! Ill put money on it that its the cause of your problem!!

 

H

HeavyMetal

NAXJA Forum User

Location

Fairfield, CT

• Mar 10, 2006

• #8

so i go down to the place to have the DS balanced and they wanted 100 dollars for the quick job. No thank you. So am i just SOL here due to fixed angles?

 

Kittrell

NAXJA Member

NAXJA Member

Location

Thornton, CO

• Mar 10, 2006

• #9

HeavyMetal said:

so i go down to the place to have the DS balanced and they wanted 100 dollars for the quick job. No thank you. So am i just SOL here due to fixed angles?

Click to expand...

If you don't wanna opt for the rebalance, then yes. Also, if the length is right, you can try to throw your rear shaft up front. If it still does it, then you know its not the shaft but your angles; which you cannot change with fixed arms. I would try this first regardless. If you pay to balance the shaft, and it still vibrates. Then you wasted a good chunk of change there.

 

H

HeavyMetal

NAXJA Forum User

Location

Fairfield, CT

• Mar 11, 2006

• #10

ill have to try out my rear DS in front, thanks for the info

 

Ben H

NAXJA Forum User

Location

Fresno

• Mar 11, 2006

• #11

Does your drive shaft have any give in it when you push it up and down or push and pull? Could have hollowed out the slip or wore off the splines? Just a thought.