73 Dart Sport Driveshaft length?

[mderoy340]

Car has a vibration at 45 mph in 3rd, downshift to 2nd goes away. New motor and tranny mounts, new rear spring bushings, new u joints, rims are straight.

I'm pulling the tailshaft to replace the rear bushing. Driveshaft in the car is 45" C to C. The yoke does have up and down play.

I measured shoving yoke forward, pulling back 3/4" and I need 46"

Anyone have a stock driveshaft they can measure? All the charts don't list a 340/727/8.25 that I've found.

 

[doug 371]

im using a 45" in my 68 val with same combo and wheel base too...no way i could fit a 46 in there...oh sorry mines 8.75 not 8.25

 

[Supershafts]

If you downshift to 2nd at the same speed. . . . . . .

It's not your driveshaft.

There is play in the bushing, so don't rule that as a problem.

But being as you change a gear and it goes away, it's somewhere else

 

[mderoy340]

Thanks for the help. I'll change the tailshaft bushing and go from there.

 

[Supershafts]

You can but, a bad bushing isn't changing from 3rd to 2nd.

 

[mderoy340]

Changed the worn tailshaft bushing and it helped but did not cure the problem. Put the tach in the car and vibration is from 1800 to 2000 rpm. Got back in the driveway and put the car in neutral and have the vibration. So the problem is in the engine/torque converter.
Will check into that tomorrow. Thanks for all the input.