Update on Shake** Need Serious Help! **

[Yedi]

Guys this is not good, brought the car back in to the driveshaft place and they checked out the whole car to find the source of my "shake" well even with all the wheels off the car has a vibration/shake. They looked at the driveshaft again, checked out good, and the rear end showed no signs/ including the gears except a very minor leaky Drivers side seal. So they said they dont really know??

To have the rear end rebuilt with new gears it's around $500-$600, thats too much.

Whats should I do, I might try to replace the bearings myself and see how that goes, but I'm not positive thats the problem. All I know is this is very annoying, and I would give anythng to find the cause of this vibration.

Anyone selling a solid rearend???

Help me out here...........

 

[The Radius Kid]

If the bearings are gone you should here a growling form the rearend when you drive it.You don't have a bent axle,do you?

 

[Yedi]

hmm, there isnt any noise when driving the car or when it's up on Jack stands and you spinn the wheels. The axles are a possibility, Any sign the axles are junk??

 

[The Radius Kid]

Look for a bent flange at the axle end.You're sure the drive shaft was installed properly?Put in proper phase?Is the drive shaft balanced properly?Stocker or replacement?

 

[MARINES185]

there is no phasing on a single piece drive shaft. every car i can
think of has a single piece drive shaft so thats not the problem.
you said when you took the drive shaft in the shop said it was
bent,right? how did they straighten it? bend it or re-tube it?
it is possible the drive shaft could be twisted. when did this
problem begin? if your drive shaft was bent bad enough it
may have destroyed the pinion bearing causing it to walk
side to side but would also create a noise. site down your
drive shaft and make sure the tops of the u-joints are in line.
this would verify that its nots twisted but the repair shop
probably would have noticed. just curious but on your pinion
yoke where the u-jiont sits do you have little tabs sticking
up? these center the u-jiont in the yoke. if not do you have
clips on each of your u-joint caps. this is another style to
center the u-joint.

 

[The Radius Kid]

Assuming we're talking about the same thing,the phasing I'm talking about[with an original drive shaft]is putting it back the way it came out ,not 180 degrees out of phase.Production tolerances can affect this sort of thing,especially if a U-joint has been replaced.That's why most repair manuals tell you to mark the position of all the parts in relation to each other when you disassemble them,to put them back together in the same relationships they came apart.

 

[Yedi]

The driveshaft is the stocker. The first time the drive shaft was just balanced and straightened. This time they re-tubed the drive shaft. ( looks like brand new) The U joints have little clips like you were talking about to keep them centered. I am positive they installed it correctly I mean all they do is drive line work for cars and heavy machinery. They said somthing about the Rear yolk be 20 degrees off or somthig and they rotated it to try to fix this problem but I did not notice anything. And they put new on new mounting pieces ( the ones with the 4 bolts to hold on the Rear U joint)

The problem was always present ever since I put this tranny and motor and the first new u joints in the car. But it wasnt that noticeable. It really started 3 weeks ago when I had a front end alignment and had the tires rotated. They checked all the wheels and tires and gave me two new wheels and tires. They even tried a totally different set of tires from a truck they ahd there and it still shook.

The car shakes even when you shift into neautral or even shut it off.

Keep the thoughts comin....... Thanks for the replys so far, I keep learning more..

 

[MARINES185]

i think you have probably eliminated the driveshaft as a
possibility. its more than likely in the rear end. as far as
phasing goes when you have a multiple section driveshaft
you must put it to gether so all the u-joints are in the same
position. if they weren't when the drive shaft is spun the
u-joints would all be taking different rotation paths. its
hard to imagine but thats whats happening. have your
differential rebuilt or get a different one.

 

[Yedi]

MARINES185 I agree with you on the drive shaft thing, I rule that out, along with the Wheels and tires. That leaves me with the rear end and the Transmission. Tommorow I'm going to the tranny place I had it rebuilt to have the tailshaft checked out ( the bearing could be bad, there is a little fluid coming out, very little) so we'll see what they say.

But eventually I think this is going to lead to having the whole rearm end checked out including the axles.

 

[6=8]

Before going to the trans shop, try blocking both front wheels (Fore and aft) and jacking up the car in the rear onto stands. Take the drive shaft off, and start/run the car. If it still vibrates, you have eliminated the rear end from the equation. If the vibration goes away, your engine and trans are not the source.

Unless the problems are a result of LOAD on the car at speed. Maybe the pinion angle changes too much under load? Do you have a broken suspension spring? Shocks? Motor mounts?

But you say this happens in neutral too? This may mean torque converter or flywheel balance weights have come loose. If auto, maybe coverter bolts or the converter itself is wasted?

I'm just tossing ideas out there. Heck, I've even experienced vibration problems from a crappy solid-core spark plug wires interfearing with spark control computers! New set of wires solved that problem!

 

[Yedi]

6=8, I was thinking of taking the driveshaft off and doing just as you said, but wont I blow Trans fluid out from the tail shaft with out the driveshaft in place? I'm curious about this.. Can I do that?????

 

[MARINES185]

you don't want to run a vehicle without the driveshaft cause
thats the only thing that that centers the output shaft on the
trans. with the driveshaft out move the output shaft on the
the rear of the trans. there will probably be alot of play. its
normal. i would rule out the trans as a source of vibration
because if an automatic trans can vibrate inside it won't last
long at all. also does this problem exist when you just rev
the car in park not moving?

 

[Yedi]

MARINES185 The car does not shake while reving it up in park. only while moving, you can feel it start shaking @ 35mph. ( just as it shakes if you are going 55 and drop it into neautral it shakes just the same, nothings changes) So there really isnt a way to run the car with out the driveshaft huh? Maybe the trans shop will know somthing I dont know.

Oh, all the shocks on the car are new along with the Motor/Trans mount

another Question, could the rear drums be out of balance, they were a replacement from the local Car Quest. Just curious if one could be out of whack, would a shop have a balancer for those??? Just an idea, I'm looking for anything at this point.

 

[MARINES185]

yedi, i chased a noise/vibration for over a year on my truck.
i thought it was pinion angle because the rear i installed was
for a coil spring rear and my truck was leaf springs. i made some
new mounts nad put it all together. went for drive and at
45-50mph would have this shake/noise. i bought a ton of
pinion shims which didn't help no matter where i had it set.
then i thought the drive shaft way have been to long cause
i had to have it lenghtened. there is a point where a drive
shaft is so long that its rotational force causes it to spin out
of balance. i made a special mount and installed a 2 piece
driveshaft. it didn't work. i finally gave up on the rear end
and installed a different one. have not had a problem since. as
far as pinion angle goes it would have to be a long ways
out to cause the problems your having. get a new rear end.

 

[Benched]

Double check your alignment also. Are the upper control arm bushings in good condition?

 

[Yedi]

Benched funny you should mention the alignment, I just had it aligned 3 weeks ago and thats when it started to shake. All the bushings on the car are in real good shape.

I went to the transmission shop today, that place is a joke. The manager guy/ main mechanic goes out for a ride with me today and tells me while we are driving " seems like an exhaust problem" What???? He was like yeah it might be too ridgid and vibrating on somthing. So then I said, so why does it do it when you put in in neautral at 55 and nothing changes and the engine is back down at 750rpm? He was like " well thats true"


So he gave me the run around and told me it seems like a chasis thing, and too check all my mounts and he walked away. All the mounts are new and tight, and why would it do it at 25-35mph with no torque on the motor and tranny??? I dont know that guy is a joke, I had to go back there like 3 times before to get my tranny leak fixed after they "rebuilt it" It's a good place and do nice work, but sometimes you gotta wonder.

So it's looking more and more like the rear end, I'm done ranting now

 

[BJM]

You mentioned the drums are new. Factory drums are balanced and have a weight welded on. Most replacement drums are not balanced. You would be surprised how much a drum can be off.