« previous next »
Pages: [1]   Go Down

Author Topic: CV Drive shafts  (Read 2107 times)

0 Members and 1 Guest are viewing this topic.

Offline bootguy

  • Member
  • Posts: 118
  • TANSTAAFL There Aint No Such Thing As A Free Lunch
CV Drive shafts
« on: February 15, 2015, 10:27:58 AM »
I have noise in both the transfer case and the pumpkins at around 40 - 50 mph.  Have rebuilt the transfer case and checked both pumpkins and put in new U-joints.  Finally got fed up and took it in to the local 4WD shop.  They said it was normal and the only way to get less noise was going to CV drive shafts.  I do plan on going to a Ford 8.8 rear end with the C clip eliminator and new axles up front while removing the vacuum disconnect. This summer I plan on rhino lining the tub to also help reduce road noise.  So the question is has anyone gone to the CV drive shafts and if so have they reduced road noise?
Logged
1994 Jeep Wrangler, 2.5L, automatic, 2.5" lift, 4:88 gearing, 33" tires, 2.5" exhaust from manifold back, air restrictor removed.

Offline Jeffy

  • Administrator
  • Member
  • Posts: 14955
Re: CV Drive shafts
« Reply #1 on: February 23, 2015, 03:20:47 PM »
Many people have gone to CV.  As for getting rid of noise, it really depends.  If you're on a stock suspension, and go with a CV, you'll likely have no difference.  If you're at a severe angle and it sounds like a can of ball bearings rolling around every time you let off the throttle, then yes it will make a difference.  Generally speaking though the reason for going with a CV driveshaft is not for noise though that's a bi-product.
Logged
Youtube Channel: https://www.youtube.com/channel/UCZNlr60GXH5OlKIFrT7P6mg
My Jeep: http://4bangerjp.com/forums/index.php?topic=2783.0
"If the motor car were invented today, there is absolutely no way that any government in the world would let normal members of the public drive one."

Offline bootguy

  • Member
  • Posts: 118
  • TANSTAAFL There Aint No Such Thing As A Free Lunch
Re: CV Drive shafts
« Reply #2 on: February 28, 2015, 08:51:59 AM »
Most of my drive is at 45 MPH and that is the sweet spot for the noise.  Only have 2.5" lift (professionally installed), so there is not a severe angle.  I will have to replace the rear drive shaft when I replace the rear axle and go with the SYE kit and plan on going to CV drive shat at that time as it is not really that much more.  The front shaft though is the problem child, Will just have to save a little more and do that one also.
Logged
1994 Jeep Wrangler, 2.5L, automatic, 2.5" lift, 4:88 gearing, 33" tires, 2.5" exhaust from manifold back, air restrictor removed.

Offline Jeffy

  • Administrator
  • Member
  • Posts: 14955
Re: CV Drive shafts
« Reply #3 on: February 28, 2015, 11:49:19 AM »
Unless you have a front locker or a LSD, the front driveshaft does not turn unless you're in 4WD.
Logged
Youtube Channel: https://www.youtube.com/channel/UCZNlr60GXH5OlKIFrT7P6mg
My Jeep: http://4bangerjp.com/forums/index.php?topic=2783.0
"If the motor car were invented today, there is absolutely no way that any government in the world would let normal members of the public drive one."

Offline bootguy

  • Member
  • Posts: 118
  • TANSTAAFL There Aint No Such Thing As A Free Lunch
Re: CV Drive shafts
« Reply #4 on: March 04, 2015, 09:46:26 PM »
Rolling down the road the drive shaft turns.  Up on blocks the wheels do not turn.  The front end was re-geared a few years ago but no locker put in and do not think it was LSD.  This next week will be upgrading the front axles and getting rid of the vacuum disconnect.
Logged
1994 Jeep Wrangler, 2.5L, automatic, 2.5" lift, 4:88 gearing, 33" tires, 2.5" exhaust from manifold back, air restrictor removed.

Offline sharpxmen

  • Chief Squirrel BlowerŪ
  • Member
  • *
  • Posts: 7093
Re: CV Drive shafts
« Reply #5 on: March 05, 2015, 07:43:24 AM »
Quote from: bootguy on March 04, 2015, 09:46:26 PM
Rolling down the road the drive shaft turns.  Up on blocks the wheels do not turn.  The front end was re-geared a few years ago but no locker put in and do not think it was LSD.  This next week will be upgrading the front axles and getting rid of the vacuum disconnect.
it shouldn't turn, something's wrong with the quick disconnect on the passenger side (unless you have a 1 piece shaft there) or maybe you have a locker of sorts or LSD like Jeffy said.
Logged
'95 YJ, NSG370 6spd / Hurst shifter, Dana 300 + 4:1 Doubler / tri-stick, Custom skid, Super D35 / Auburn LSD / 4.88, 35x12.5x15 BFG KM2, 64mm t/b, 1.7 RollerRockers, MkVIII e-fan, Dual Diaph Booster
Latest: Corbeau BajaRS heated seats :dance: keeping warm the rear end

Offline Jeffy

  • Administrator
  • Member
  • Posts: 14955
Re: CV Drive shafts
« Reply #6 on: March 05, 2015, 02:28:33 PM »
I bet someone put the vacuum disconnect plug on backwards.  Which is why you get a noise and probably vibrations at 40-50.  That's about where you'll start to feel vibrations from the front shaft turning.

The line should look like this:

« Last Edit: March 05, 2015, 02:28:58 PM by Jeffy »
Logged
Youtube Channel: https://www.youtube.com/channel/UCZNlr60GXH5OlKIFrT7P6mg
My Jeep: http://4bangerjp.com/forums/index.php?topic=2783.0
"If the motor car were invented today, there is absolutely no way that any government in the world would let normal members of the public drive one."

Offline AWK

  • 4BangerJP.comŪ Donator
  • Member
  • *
  • Posts: 45
Re: CV Drive shafts
« Reply #7 on: March 06, 2015, 09:53:13 AM »
Would this be the same for a 97 TJ?  I am thinking mine turns.

AWK
Logged

Offline Jeffy

  • Administrator
  • Member
  • Posts: 14955
Re: CV Drive shafts
« Reply #8 on: March 06, 2015, 12:17:21 PM »
Quote from: AWK on March 06, 2015, 09:53:13 AM
Would this be the same for a 97 TJ?  I am thinking mine turns.

AWK
No, TJ's are different.  They don't have a disconnect and so it turns.
Logged
Youtube Channel: https://www.youtube.com/channel/UCZNlr60GXH5OlKIFrT7P6mg
My Jeep: http://4bangerjp.com/forums/index.php?topic=2783.0
"If the motor car were invented today, there is absolutely no way that any government in the world would let normal members of the public drive one."

Offline bootguy

  • Member
  • Posts: 118
  • TANSTAAFL There Aint No Such Thing As A Free Lunch
Re: CV Drive shafts
« Reply #9 on: March 06, 2015, 06:56:56 PM »
Am going to go look at the Vacuum lines tomorrow, but I have a set of solid axles going in next week.  Will have a better overall picture once I get this work done.
Logged
1994 Jeep Wrangler, 2.5L, automatic, 2.5" lift, 4:88 gearing, 33" tires, 2.5" exhaust from manifold back, air restrictor removed.

Offline Jeffy

  • Administrator
  • Member
  • Posts: 14955
Re: CV Drive shafts
« Reply #10 on: March 06, 2015, 08:09:55 PM »
A one-piece axle shaft will make the driveshaft spin as well.
Logged
Youtube Channel: https://www.youtube.com/channel/UCZNlr60GXH5OlKIFrT7P6mg
My Jeep: http://4bangerjp.com/forums/index.php?topic=2783.0
"If the motor car were invented today, there is absolutely no way that any government in the world would let normal members of the public drive one."

Offline jfrabat

  • Gargantuan Mango Tree MechanicŪ
  • Member
  • *
  • Posts: 3676
  • Finally USING the Jeep!
Re: CV Drive shafts
« Reply #11 on: March 10, 2015, 11:30:25 AM »
Quote from: bootguy on March 06, 2015, 06:56:56 PM
Am going to go look at the Vacuum lines tomorrow, but I have a set of solid axles going in next week.  Will have a better overall picture once I get this work done.
With solid axles, as Jeffy said, the shaft will spin.  Just get a balanced shaft and call it good.  I put a Tom Woods shaft on mine when I went to solid axles, and have not had any problems with vibrations...  The rear one I did kill once (wheeling will do that), but never had issues with the front...
Logged
'94 YJ 2.5L with 4" RE lift, Superwinch EPi9.0, FoMoCo e-Fan, SD30 and SD35 w/ARB-5.13, 165A alt., 33" BFG KM2 on 15" AR wheels, Sony sound system, Pavement Ends Hardtop, Hydroboost

Offline Bounty Hunter

  • Member
  • Posts: 1658
    • http://www.sija.org
Re: CV Drive shafts
« Reply #12 on: May 06, 2015, 09:59:18 AM »
The mechanic that told you to install CV driveshafts to get rid of a noise is an idiot.  Non-CV Driveshafts are quiet if in good condition and your ujoint angles are correct.  I would find a different mechanic to track down the noise before something goes real bad.

You can't install a CV driveshaft up front unless your pinion is pointed directly at the transfer case yoke.  Can't do that unless you cut and turn the inner-C's.
Logged

Offline bootguy

  • Member
  • Posts: 118
  • TANSTAAFL There Aint No Such Thing As A Free Lunch
Re: CV Drive shafts
« Reply #13 on: May 11, 2015, 10:11:10 PM »
Put in the solid axles and at the same time replaced the U joints again.  road noise was less but with the 2.5" lift I saw that the shaft was extended quite a good 1.5".  I am going to replace the drive shaft, but will have to measure for length.  So a little bit of research to do.
Logged
1994 Jeep Wrangler, 2.5L, automatic, 2.5" lift, 4:88 gearing, 33" tires, 2.5" exhaust from manifold back, air restrictor removed.

Offline Bounty Hunter

  • Member
  • Posts: 1658
    • http://www.sija.org
Re: CV Drive shafts
« Reply #14 on: June 01, 2015, 11:28:18 PM »
Quote from: bootguy on May 11, 2015, 10:11:10 PM
Put in the solid axles and at the same time replaced the U joints again.  road noise was less but with the 2.5" lift I saw that the shaft was extended quite a good 1.5".  I am going to replace the drive shaft, but will have to measure for length.  So a little bit of research to do.
Make sure the ujoint angles are correct for a non-CV driveshaft.
Logged
Pages: [1]   Go Up
« previous next »