U joints

[jansen29]

Here is the next issue I have.. I just had a custom drive shaft made and balanced and I now have to replace my third rear u joint. Is it possible they made my drive shaft a bit to long and how much of the input shaft should be inside the trans. I have a T-5 from a 88 5.0 mustang with the 157 tooth fly wheel and a quicktime bell housing.
Any ideas would be great because u-joints do not grow on trees.

 

[78CobraII]

I'm sure there is a more technical answer...but I've always heard that you need at least 1 inch travel at it's installed depth. So when it's in, it should have at least 1 inch more travel before it bottoms out.

Bottoming out is bad on both the trans and the rear end.

You could always disconnect the rear shocks, put someone in the rear seat and have someone bounce the rear of the car while checking the driveshaft for contact.

 

[Wart]

I'm sure there is a more technical answer...but I've always heard that you need at least 1 inch travel at it's installed depth. So when it's in, it should have at least 1 inch more travel before it bottoms out.

THats about right.

I've measured from the seals wear on the yoke to the yokes shoulder and have come up with ~ 1", or was it 3/4 inches ... If I remember I'll find the V-6's yoke and measure it.

One of the truths of trans yoke "distancing" is its immeasurably better to have WAY to much sticking out than ANY too little.

Bottoming out is bad on both the trans and the rear end.

Bad for the rear, potentially fatal for the transmission.

You could always disconnect the rear shocks, put someone in the rear seat and have someone bounce the rear of the car while checking the driveshaft for contact.

Thats an idea, as the leaves flatten the rear is moved aft and hte pinion is rotated down, but then with thrust the axle rotates and the pinion climbes and things can get real short/tight really quick. So bouncing the car is a tool but shouldn't be considered definitive.

Since this has the T-5 you may want to search for a thread about T-5s and drive shaft vibration. I'm not writing all that again.

 

[jansen29]

Thanks guys,

That is the issue my so called custom drive shaft is about 1 3/4 in to long. I am going to put my new 8.8 in next week and then have the drive shaft changed again off the new rear end. Good thing I'm not driving the car to much right now. Again thanks for the help.

 

[Wart]

Thanks guys,

That is the issue my so called custom drive shaft is about 1 3/4 in to long.