Supers

You too, give a little more detail...

I would say you need to pick up the pin angle just a degree

STEEPSS

iTrader: (30)

More detail on what?

Cut and dried, all that was changed:

1. Different (used) gears
2. Brand new 5" 1350 pinion yoke
3. New driveshaft (old one vibes too, and didn't before)
4. Axle was moved to the front of car ~3/4" to clear 28" tires.

NO vibrations before this.

NHRA4MULA

iTrader: (29)

Did you put in new bearings or did you press the old ones off and back on and where did you get the used gears ??? I'll bet your problem is in the used gears or bearings if they were pressed on and off they may have gotten messed up... did you turn the rear from the driveshaft by hand and it turns nice and smooth and with no chunking feeling ???

STEEPSS

iTrader: (30)

All new bearings were used. Driveshaft / rear turns freely, no obstruction or abnormality.

It about has to be the gears or the posi. I re-used the Soft Locker that was in it, but it was fine before :?

STEEPSS

iTrader: (30)

Talked to the guys as Quick Performance a little bit ago. As I have a solid pinion spacer, I can remove the pinion nut / yoke and replace it with another.

So I did that, put the old (short) one on, and the stock driveshaft.

Vibration remains unchanged. It's definitely not the driveshaft, or the pinion yoke.

That only leaves the output shaft bushing in the tranny, or somethiing in the center section. FML. Oh well, it's not like I enjoy driving my car or anything.

NHRA4MULA

iTrader: (29)

is the vibe the same in gear off the gas as out of gear off the gas at 50-60 mph

Supers

This is like beating a stubborn horse...

Let me try this, if i can not drive your car i have to diagnose it thru you....

So if you do not GIVE explicit detailed info, you will have a "Drive line Vvvvvvibrrratttttion. Exhausting your options" or you will replace Everything to find out possibly it wasn't that....

STEEPSS

iTrader: (30)

What exactly the **** do you want? A video? and PS I haven't spent a dime replacing anything. If there was a shop within 100 miles of here that was even a tad bit performance oriented, I wouldn't be wasting my time on this ******* website, now would I?

To whom it may concern:

The vibration is of utmost amplitude when nearing 50 MPH. It is a shuddering feeling, increasing dramatically with speed. It is not dependent on accel / decel. It only has to do with speed. I think it would be very prudent that I not exceed speeds in the general range of 70mph, lest my car falleth the **** apart.

LPE 403

iTrader: (6)

Lol, you mean there isn't anyone in quaint Junction City or the scenic speed trap known as Ogden that can help ? Spent a little time in Ft Riley once upon a time and understand your frustration...

Sorry man, I hope you get this thing fixed.

NHRA4MULA

iTrader: (29)

this may be stupid but do you think the posi unit may have a crack in it from pressing the bearings on and off .. I have done a lot **** with rears and this sounds like a couple of things #1 a needle bearing in the ujoint in the bottom of the cup making the ujoint off center/binding ...but you changed the drive shaft and it was still there # 2 torque arm/pinion setting way off and ujiont binding /something wrong with bushings on TA may look ok but moves/ but vibe/sound should change under load and free wheelin #3 bearings on the posi unit not pressed all the way on or on crooked or unit is cracked from pressing bearings on and coming apart ...I dont think it would be in your axles and if it was brake related it would get worse the hotter it gets and there would be some kind of drag/pulse on the car ...if it not the pinion angle it has to be the posi unit is not seated .. I dont think it would be the gears because you said the rear rotates freely with no binding but that almost rules out the posi unit unless when going in with the axles something moved like springs or clutches ..did the axles go in nice and smoothe all the way down ....because 2 things stayed the same when you changed all the old to the new and back again the pinion angle and the posi unit with the used set of gears and I really dont think it would be the gears I would check the pinion angle and the torque arm .....maybe a bolt broke or some **** like that on it ...just tryin to help the one thing thats for sure is sooner or later it will show its ugly face ...I think it has some thing to do with the pinion angle...good luck I hope you find it before it shows itself ps does the old pinion still have the bearings onit put the old ring and pinion back in and see what happens then but make sure the pinion angle is on the money first this being off will make **** vibe like crazy

Supers

Performance has nothing to do with your problem...

maybe you have the wrong joint in the shaft...

When i say DETAIL, i would expect this..

When i start off i have nothing maybe a slide shudder but quickly goes away in like 200 rpm, approaching 38mph it barely starts to become a audible noise then at 45 it starts to become a vibration, letting off the gas or going to a different gear has no effect as long as you stay at that speed or go faster. IF you go faster it does ______ if you get to 85 it is gone, or it is worse

Got the idea of detail.........

Not i got a vibe it starts at 50 and gets worse if you go faster is anything but a customer on the phone that gets this reply, my address is see you in a little while.

With the very little bit of info you gave you either have the wrong joint or a bent shaft, or maybe 2 bent shafts or 2 shafts with the wrong joints...

Or your rear is falling out....or you left everything loose...


Since you want a performance shop how about zombies at 818 Manning Winfield, KS 67156 (620) 402-6157

Or

Vettes And Performance (913) 362-8388, 3115 Merriam Ln, Kansas City, KS 66106

Or

Motorsports Of Kansas City Inc (913) 334-0477, 6285 State Ave, Kansas City, KS 66102

The only other advice i got for you is to drive it at the worst part and stay there till it breaks then you'll know EXACTLY what it was...

STEEPSS

iTrader: (30)

I apologize for that last post. I was having a BAD day. I appreciate the advice, and I'll go drive it again, so its fresh, and give a detailed report.

NHRA4MULA

iTrader: (29)

did you find the vibe ??????????????

STEEPSS

iTrader: (30)

No. I haven't touched it since I last posted. My other project has been keeping me busy. I'll likely be pulling the center and having it checked out. That's about the only thing it COULD be at this point. Unless, however, the tailshaft bushing just decided to show its malfunction with the lower gears? Either way, its driving me insane.

STEEPSS

iTrader: (30)

I had they guy that built the center stop by today, and go for a ride. It appears that it has loosened up, among possible other things (?bearing failure?). So I'll be pulling that, and getting it to him ASAP. Likely the first of the week or so. Till then, I'll be putting all my precious free time towards my 280z project, and the wiring associated with it.

STEEPSS

iTrader: (30)

Just got the center back from my guy last night. Turns out it was set up with the pinion .020 too deep. The measuring method he used the first time was inaccurate. I'll hopefully be installing it again in the next couple days, so i'll have more to report then.

armyboyatc

iTrader: (29)

Let us know what you find. I am interested to see.

LS1-IROC

iTrader: (4)

.020 too deep!!! Holy crap that's a ton.

I changed the pinion depth on my 9" by .003 and the car vibrated like a **** at anything above 50mph.

studderin

iTrader: (28)

ya steeps how is it now???



4. Axle was moved to the front of car ~3/4" to clear 28" tires.

so you had 26 before? what did you do with the PA in the rear, when you said you tired changing it? if you have a poly trans mount, and a aftermarket trans Xmember you can get a vibration form the front u joint not being happy. take out theat poly "preload spacer" under the mount, see what thats dose. You might even have to space down the trans Xmember to adjust for the rear end being lowerd. 1 or 2 good washer between the Xmember and the body can make a big difference.

STEEPSS

iTrader: (30)

Well I just ran the car on stands, and the vibration has moved to a higher mph, but it's still there, although considerably less than before.

I have no idea about rear ends. I THINK that's what he said.


Well I actually have 26" street tires, and 28" slicks. After everything was adjusted as it should be, I set the pinion angle to -2*. I am running a poly trans mount, and poly motor mounts. I am also using a stock cross member. I might try the washer trick, but the pinion angle is correct, so I don't really see what the issue is. I'm going to put the exhaust on it here in a bit, and go drive it. I'll know more then. I just want it to be fixed!