I found my vibration after my rearend rebuild..

[youwish2bme]

After completely rebuilding my rearend/suspension I have had a vibration at 75mph and above... Well after checking the driveshaft,halfshafts,alignment,balancin g the tires,I think I found it.. It required once again removing the differential to see that one of the yokes is not made correctly. I just wanted to provide this information to others so that you don't have to go thru the hassle of the installation of your rearend only to have to remove it again.. I used the HD cap style yokes for my differential b/c as those that know me.. I like to get on my vette...

Here is the passenger side yoke this one looks good..

Here is the drivers side yoke and the left measured from the yoke to the dust cap is about 18.5 mm the right side is 9.5 mm from the yoke to the dust cap...

Jeff thanks for giving me those calipers b/c mine would not have been able to measure this with out them..

Bill I'm glad we finally found it, I guess I'll be off the road for a couple of days and miss the Waterside event but hey this was too important not to fix.... So if anyone was going to Waterside and didn't register there is now an open spot....

I have already talked to the vendor and they are going to replace it so no need to ask whom it is. Just if you are rebuilding your diff with those HD yokes check them to make sure that they are true...
Dave...

 

[Vette66AirCoupe]

That's some great detectivce work outta you! Some pretty resourceful camera work too I might add. Thanks for sharing the knowledge.

 

[Viet Nam Vett]

After completely rebuilding my rearend/suspension I have had a vibration at 75mph and above... Well after checking the driveshaft,halfshafts,alignment,balancin g the tires,I think I found it.. It required once again removing the differential to see that one of the yokes is not made correctly. I just wanted to provide this information to others so that you don't have to go thru the hassle of the installation of your rearend only to have to remove it again.. I used the HD cap style yokes for my differential b/c as those that know me.. I like to get on my vette...

Here is the passenger side yoke this one looks good..



Here is the drivers side yoke and the left measured from the yoke to the dust cap is about 18.5 mm the right side is 9.5 mm from the yoke to the dust cap...



Jeff thanks for giving me those calipers b/c mine would not have been able to measure this with out them..

Bill I'm glad we finally found it, I guess I'll be off the road for a couple of days and miss the Waterside event but hey this was too important not to fix.... So if anyone was going to Waterside and didn't register there is now an open spot....

I have already talked to the vendor and they are going to replace it so no need to ask whom it is. Just if you are rebuilding your diff with those HD yokes check them to make sure that they are true...
Dave...

I think this will show it a little better.... More meat on the yoke on one side then the other....Sorta like a cow with 2 different size utters...UB...(Unbalanced)..:L

 

[allcoupedup]

Thanks for sharing. Momma always said the best way to avoid problems is let other people deal with them first!

Brian

 

[Viet Nam Vett]

Thanks for sharing. Momma always said the best way to avoid problems is let other people deal with them first!

Brian

Yeah Brian....Now when I get home ..I'll check mine...I have the same HD Yokes..!!

Thanks Dave for pulling your rear diff for the 3rd time..

 

[youwish2bme]

Yeah Brian....Now when I get home ..I'll check mine...I have the same HD Yokes..!!

Thanks Dave for pulling your rear diff for the 3rd time..

Alrighty then.. I finally got done doing the other stuff out there in the gerage... Here are a few pics with my new set of calipers (thanks again Jeff)...

The bit is only to give me a common reference and is wedged in. I could not verify that it was square so... It looks like the u-joint trunion is indeed still centered or very close. Without being being able to verify square my numbers could be scewd. however the mass is at a massive imbalance as Mark (VNV) said to me..

Mark also I haven't emailed Bill but that poly mount looks to be to tall.. I installed it and it ended up raising the #@%#ing dash... Sooo when you reinstall the body watch the tunnel closely... I pulled it back out btw... Oh and yea I'm getting to be a real pro at busting the rearend apart...Lucky me...

So with out further ado.. Let me know what you guys think...
This is the what we will refer to as the R side it measures 50 mm

This is the L side it measures almost 60 mm in width

This is measuring from the R side to what I was assuming as a center pt of the yoke this measures 177.5 mm

This is the L side to center 172 mm

Let the games begin... Thanks as always.. Dave..

 

[Viet Nam Vett]

Mark also I haven't emailed Bill but that poly mount looks to be to tall.. I installed it and it ended up raising the #@%#ing dash... Sooo when you reinstall the body watch the tunnel closely... I pulled it back out btw...

The Poly mount that I have was the same height as the Keisler mount. Now I'm confused.....:L .

Tha Kiesler mount sank down about 1/4 " when the weight of the tranny was put on it. The poly mount doesn't compress. Did you measure the "UNCOMPRESSED'' thickness of the stock keisler mount and compare it to the poly?

 

[youwish2bme]

I'll pull it back out tomorrow and take a close look at it.... Oh the joys.. I think between the two of us we've cornered the market on aftermarket crap..... Dave....

 

[Viet Nam Vett]

I'll pull it back out tomorrow and take a close look at it.... Oh the joys.. I think between the two of us we've cornered the market on aftermarket crap..... Dave....

We Certainly did "Oly".......

Heh I just went out and double checked my measurments.. I'm wrong..!! The Poly mount adds 1/4" to the height of the tranny but gives me the correct Yoke and Drive shaft and Pinion angles.

So...that 1/4 " really jacked up your dash?????

After Market Fits Like Crap

Buy Nos

After Market Is For Buba

 

[youwish2bme]

It was enough that it caused where you normally have bonded at the bottom of the waterfall/center console to raise up between a 1/8 to a 1/4.... But we both know my vette is no where close to original... may look it but closer inspection reveals otherwise... Your coupe may end up clearing with no problems... But you know as I do it's tight in that tunnel just forward of the shifter.....So raising the tranny any will be tight....Sometimes I think that I need a vacation from my hobby. To much stress for a 20 something.....Dave...

 

[Viet Nam Vett]

It was enough that it caused where you normally have bonded at the bottom of the waterfall/center console to raise up between a 1/8 to a 1/4.... But we both know my vette is no where close to original... may look it but closer inspection reveals otherwise... Your coupe may end up clearing with no problems... But you know as I do it's tight in that tunnel just forward of the shifter.....So raising the tranny any will be tight....Sometimes I think that I need a vacation from my hobby. To much stress for a 20 something.....Dave...

To much stress for a 20 something.....Dave...

Yeah..too much stress for a 50 Something....Me But keep at it...when it's all done you know it will be correct and you will be an expert becuase you have done it. And you will enjoy your vette more becuase you built it..!!!!

I have taken things off and on my vette numerous times untill I got it right. Like Bill says.... "Don't be a Bubba" If your going to do it ...do it right.

I'm sure plenty of guys here on the forum have also done this. It's the nature of the hobby. As long as your on this forum..you'll have all the help you'll need.

 

[IH2LOSE]

Wow I have so say I never would have looked there assuming they just could NOT be manufactured wrong. Great find and thanks for sharing.


I hope that was the only out of spec part you have in there.

Just an adder here, every one has heard the term balanced and blue printed,in motor building terms.This is what they do to our motors. these little things all add up to rob HP from us.
That is one of the reasons I had always belived in having a motor built over purchasing a crate engine.

 

[youwish2bme]

Guys I just wanted to put out there that Mid America really stepped up to the plate and after looking at the pics granted me a full refund on the yokes all three of them.. I ordered a replacement from them and it was the same way as the bad one. They did exactly what any jobber should do. So Bravo Zulu to Mid America in taking care of their customers

Dave...