Ferocity02

iTrader: (59)

Since doing the 80E swap I am getting a vibration under acceleration. It is most noticeable at low speeds and shakes the whole truck. It is less noticeable at high speed. During normal driving it does not seem to vibrate. This never happened before the 80E.

It's the stock 2-piece driveshaft. Had the slip yoke, u-joint, and center support bearing replaced and the entire assembly balanced when the 80E went in.

My pinion angle should be okay, it did not change by swapping transmissions. But the angle of the 1st shaft to the slip yoke may have. Anyone had to shim the trans?

Vortec350ss

iTrader: (20)

I get a slight vibration out of mine too... my driveshaft was a little too short and a longer shaft made it better... but hasnt completely solved the problem honestly.

GMCtrk

iTrader: (27)

Nobody addresses this issue with the 80e swap but I raised discussion about it a long time ago. Although the length of the 60 and 80e trannies are very similar the mounting position for the transmission mount is much different such that the height of the output shaft is significantly different between the two. This leads to differences in driveshaft angle, likely accounting for the vibration. I've had this issue as well and have minimized it but not completely eliminated it. My truck is so low to the ground I can't get under it to measure the driveline angles and haven't had a chance to get it up on a lift.

Ferocity02

iTrader: (59)

Interesting. I wish I measured the 60E before selling it. I had a similar issue with the T56 I swapped in. Its mount was much lower than the 60E, so it raised the back of the trans up, so much that the stock exhaust was hitting the floor board! I ended up bending the exhaust a little and using a thinner poly trans mount from Energy Suspension.

What have you done to minimum the vibs? I need to measure as well.

timmay208

iTrader: (4)

I have my stock 603 and 80e out right now. ill do some measurements tomorrow. My truck has the 1 piece driveshaft, gonna be taking mine down soon to be modified

Fast355

Not sure how you guys setup your crossmembers but I adjusted for the mount height when I modified my crossmember. In the Express all I had to do was pickup a shorter yoke as the 60e yoke was about 8" long and had the shaft balanced. My stock shaft had a vibration that was really noticeable at 80+ mph. One of the first things I noticed was how silky smooth it was well past 100.

BlackGMC

iTrader: (31)

When i had mine out during the swap. I measued the 60 vs 80 and the 80 was actually slightly shorter. Believe it or not.

Jetn3

How about guys who are using pt member, dirt track racer 81's, 80e swap crossmembers? Any vibration with these? I got one these for future swap.

timmay208

iTrader: (4)

I doubt the crossmember has anything to do with it

timmay208

iTrader: (4)

That seems odd? Every truck ive seen with a 80e swap has had to lengthen the crossmember and shorten the drive shaft

so you had to get a longer drive shaft and shorten your crossmember?