CV driveline angles...

[P&T Jeeps]

My buddies YJ is encountering a driveline vibration which we cannot fix. It began after the installation of a SYE. It is not your common acceleration or deceleration vibration. It is speed sensative; it starts at 50 then gets substantially worse at 70.

His pinion was about 2.5 degrees below the driveshaft then we moved it up to parallel to it with no luck. Both front and rear driveshafts have been balanced and the tires are zeroed out.

So what other variables are there? Where should the pinion be in relation to the driveshaft? Parallel has worked on all of the other vechicles We've built.

[onetoncv]

first off do your mirror's get fuzzy? and is it kinda of on float or all the time? does youd hood kind of bouce up and down at 65 mph? and did you try taking your c/v off the t-case and 180'in it? does this make it worse or better? give me call if this all sounds weird- Jess 530-877-2875 be happy to help- High Angle Driveline

[YJAMES]

Thank you for the info Jess. I will let you know what happens.

[bluesman2a]

Originally posted by onetoncv:
<STRONG>first off do your mirror's get fuzzy? and is it kinda of on float or all the time? does youd hood kind of bouce up and down at 65 mph? and did you try taking your c/v off the t-case and 180'in it? does this make it worse or better? give me call if this all sounds weird- Jess 530-877-2875 be happy to help- High Angle Driveline</STRONG>

Hey Jess, bear with me here, I'm trying to learn from the master... I have a similar problem and here are my answers to your question:

Setup: CJ-7 with NV4500/Atlas II running a CV shaft to an AMC 20.

1) Mirrors do get fuzzy.
2) It's not all the time, but worst at speed, under acceleration.
3) Yes, the hood bounces.
4) haven't tried 180'ing the shaft. Would be easy to do though, what does that tell me?
5) Also, can feel a lot of the vibes (rocking back/forth)in the shift lever. The tranny mount is new, so I don't think it's that.

[ 08-15-2001: Message edited by: bluesman2a ]

[Folke]

Me too!!!!

After I installed a SYE+new driveshaft I had some speed related vibes. I found out that the driveflange on the SYE was slightly out of whack. Got a new one and it worked better.
One of the guys at Denny's Driveshaft (highly recommended)told me that if the CV/joint/driveshaft is as little as 0.002" off, it can give you vibes.

HTH

/F.

[ 08-15-2001: Message edited by: Folke ]

[Keith]

any update?

[P&T Jeeps]

yea, we fixed it. how? I've got no fawkin' clue, as I can't remember back that far. I've done way too much other chit to too many other rigs since then.....


Damn Keith, searching all the way back to '01? 3/4 of the current members didn't know we existed back then....ah, the good 'ole days.

what do you exactly do you need? ask the Q & it might spark the memory....

[Keith]

I was just fawkin around, reading some old posts. Thought I would try to get a Tuesday newb to bite a day early.

[onetoncv]

Originally Posted by bluesman2a

Hey Jess, bear with me here, I'm trying to learn from the master... I have a similar problem and here are my answers to your question:

Setup: CJ-7 with NV4500/Atlas II running a CV shaft to an AMC 20.

1) Mirrors do get fuzzy.
2) It's not all the time, but worst at speed, under acceleration.
3) Yes, the hood bounces.
4) haven't tried 180'ing the shaft. Would be easy to do though, what does that tell me?
5) Also, can feel a lot of the vibes (rocking back/forth)in the shift lever. The tranny mount is new, so I don't think it's that.

[ 08-15-2001: Message edited by: bluesman2a ]

Okay the hood bouncing is a tire problem -mirroirs fuzzy is high frequency and may be angle realated or balance realated driveline - but it reminds me allot of an angle problem -under load is mainly mount problems or angles on the shaft- sooo the big question what are your angles i want a graph -t-case angle -shaft angle -pinion angle and off-set angle ? what you say- check any off-set from the t-case center line to diff center line sideways- and check it carefully -don't poke your head in there and say its all good huh- Jess

[lugie_98tj]

Jesse answered a 3-year old question...nice

[Suprsizit]

Maybe a 3 year old question but I'll bet it's not out of date...

[fubar73cj5]

I'll bite on DFT

Hey Jess,

I thought that a cv should be run with the pinion 1 degree downward at ride height, not directly at the t-case, is this correct?

I'll be in touch in a month or two, it's almost that time...

Justin

[Keith]

Originally Posted by fubar73cj5

I'll bite on DFT

Hey Jess,

I thought that a cv should be run with the pinion 1 degree downward at ride height, not directly at the t-case, is this correct?

I'll be in touch in a month or two, it's almost that time...

Justin

Running it at zero causes premature joint failure. So yes, a touch of angle is good. I have heard one to three is ok.

[fubar73cj5]

Right on, nobody likes anything that's premature

Thanks for the info

[Comet]

Doug, is that you?!?! You crusty fawker how the hell are ya?
BTW, Jess, thanks again for making me a happy customer. Hopefully my junk is going under the knife this spring for a serious drivetrain/suspension overhaul so I'll be calling again before long!

[LilRocky]

Hey, Jess-

How much TC output to pinion offset you willing to live with?

[rock-rod]

Originally Posted by Keith

Running it at zero causes premature joint failure. So yes, a touch of angle is good. I have heard one to three is ok.

I have heard this too. I think it was specifically for leaf sprung vehicles to counteract the pinion rolling up and going past the centerline of the DS.

How about link suspensions, should the pinion be straight at the DS centerline with the suspension static-weighted?

[Mudmonster]

i thought it was to make the caps spin just a little to keep the needles greased.

and yeah how much offset is ok with a CV shaft