[Bobs36ford]

Originally Posted by prostreet6t9

I would raise the rear up a little. Take a 1/2" of washers and put them in between the trans mount and the trans with the mount bolts going thru the washers. Run the car on jack stands and see if it helps any. You can experiment with the thickness to see if you can make the shake better or worse.

If you find a spot that makes it better you can make a aluminum spacer with the thickness that worked best.

Its hard to tell by the pic... Depending on how long that slip yoke is,it almost looks like the D/L may be a little short.

If you get a chance you might post a pic of the rear angle also.

It sounds like a great idea. I'm going to take you advise right away. This problem started when i raised the front end 2 inches

[prostreet6t9]

The rear is almost "Too" straight. With a little Spring wrap the pinion may go above the center line. But.... If you raise the front,the rear may look pretty good. I would mess with the front first and see how it turns out.

[Frisco]

Originally Posted by prostreet6t9

Its hard to tell by the pic... Depending on how long that slip yoke is,it almost looks like the D/L may be a little short.

The yoke does appear to be too short. The rear seal on the trans tail shaft appears to be worn out. There also looks like three rings worn into the O.D. of the slip yoke. Evidently they are old, as they are rusted looking in the pic.

If the yoke is in fact too short, it can not only wear out the seal quickly but it could be the source of the vibration.

The angle doesn't appear to be anywhere near 20 degrees in the pic. How did you determine the angle?

[Bobs36ford]

My 36 Ford has a 350 Chevy engine with a Chevy turbo transmission. I have a vibration at 20 MPH when engine is pulling. The U joints have been eliminated and a back yard mechanic says it could be my trans. Is that possible or do you have any other ideas?

Bob

[Frisco]

Originally Posted by Bobs36ford

My 36 Ford has a 350 Chevy engine with a Chevy turbo transmission. I have a vibration at 20 MPH when engine is pulling. The U joints have been eliminated and a back yard mechanic says it could be my trans. Is that possible or do you have any other ideas?

Bob

Did you check to see that the front yoke is installed to the correct depth on the trans spline?

This was previously covered on your two earlier posts concerning the vibration.

If the front u-joint yoke is not inserted far enough into the trans tailshaft, you will experience vibration as well as premature failure of the trans rear seal and the bushing in the trans tailshaft as well as the front u-joint.

In the pics you posted it appeared that the yoke was not in far enough. The only way to correct that is by having the driveshaft length made longer to enable the front yoke to be installed at the correct depth.

The correct depth is usually found by inserting the yoke all the way in and then backing it out about 3/4". When the yoke is installed this way the correct driveshaft length can be determined by measuring from the center of the front u-joint to the center of the rear u-joint.

Your "backyard mechanic" may be correct if the transmission mounting bolts are missing and/or the mount itself is broken. I would expect the vibration to occur more often than at 20 MPH if that were the case.

[Bobs36ford]

The bushing in the trans tailshaft seems to be OK....only about 1/64 play when I push it up & down.
I will have to pull the drive shaft to measure and see if i have the 3/4 backing out play

However I do have too much play when shafting from drive to reverse. This makes a bump noise. I cut idol speed down but didn't help.

I'll try to get to pull drive shaft soon.

Thank you for your advise

Bob

[Crosley]

I have merged bobs36ford two separate threads into one on this vibration problem.

In the earlier photos the drive shaft angles are incorrect and the yoke at the transmission appears too far out if the vehicle is at ride height when photo was taken