86' 720 drive shaft

[Guam Soldier 671]

hey, i was wondering if someone can help me out... my drive shaft center bearing gave out, so i parked the truck for a month and a friend told me to go and get my drive shaft welded to be a straight single shaft, but when i brought my drive shaft to my local machine shop, the guy told me he cant eliminate my center bearing, and instead told me to find a longer shaft so he can cut the brackets off my original drive shaft and welded to the long shaft (offcourse he's going to cut it as the exact lenght as the stock) but my question is where do i find a longer shaft that is the same circumference as my stock shaft?

[datzenmike]

The bearing almost never goes bad. What happens is the rubber doughnut around it rots away and without support, the driveshaft becomes unstable and vibrated under load.

 

What I did was remove the driveshaft and wrap an inch and a half wide strap of rubber conveyor belt around the shaft to build it up. The conveyor belt was discarded by a gravel pit and was about 1/4" thick and really hard to slice with a box cutter. I managed maybe a yard long? piece and wrapped it around the center bearing area until it would clamp down tightly in place. I meant to replace it later when I found a new rubber doughnut but it worked so well I left it there for several years. A perfect fix and zero dollars cost. Any rubber strip or strap will do just make it a tight fit. Good luck.

[ggzilla]

Or just buy a new one bearing support from Nissan - less expensive than modifying the shaft The center bearing type is quieter and smoother.

[Guam Soldier 671]

thanks... so i'll just replace the rubber doughnut..

[wayno]

thanks... so i'll just replace the rubber doughnut..

Seems like the guy at the driveline shop would have told you all you needed was the rubber doughnut.

Another thing that bothers me is the fact that a driveline shop doesn't have the material on hand to make a one piece driveline, do you have another shop you can go to?

[Guam Soldier 671]

actually yes there's two machine shops around my area, but both are out of the circumference measurement of my original shaft... because where im from a lot of datsun truck groups attack the driveline they were selling....

[MikeRL411]

Judging from the multiple posts you sure do have a lot going on with your 720!

[Guam Soldier 671]

finally got the time to work on my 720... (project truck)

[bryant2482]

yea autozone, oreilly and ebay have the rubber doughnut. or you can do what i did and hit up the junk yard and pull out a solid drive shaft