Has any converted from a 2 peice drive shaft with a center bearing to a 1 peice with out a center bearing? Or is there a reason why my 85 pickup has a 2 peice and my buddy 85 4-runner has a 1 peice?
Thanks
J.D.

 

Yep. and Yep.

 

Okay, just havin fun. Your buddies was probably one of the early retrofits, unless someone has changed it since.

The first Xtracabs came with 2-piece driveshafts. They had problems with a vibration. Odd thing too, not just at speed like a balance issue, but it would start at maybe 3 mph and increase with speed, a very noticeable pulse like you running over little speed bumps all in a row. Toyota's first answer was it that it was normal and to ignore it. (Some things never change...) But, some people (like my father, who bought the first SR5 xtracab 4x4 to show up at the dealership,which he still has by the way and it now has 300k on it) would not accept this and kept complaining. Toyota did all sorts of stuff, balancing the shafts, changing u-joints, injecting foam into them, external balancers etc... They finally retrofitted )based on complaint) a lot of em to one-piece driveshafts and problem cured. Later they must have worked out the issue because I see that they went back to 2-piece driveshafts or continued to use them or whatever. (I'm now sure it was the combination of the angles from the output flange to first shaft to the second shaft to the pinion, because years later I did a bunch of that very engineering for my company...) Seems to me, but I wouldn't swear, that the first ones didn't use a cardan joint at the carrier bearing, they used a single u-joint. I could be wrong, I can't remember what I had for lunch so I sure can't remember looking under a few Toyotas at my father's dealership 20 years ago...

 

4Runners should have the 1-piece stock, my '85 did. The 2-piece shafts were used on the longer wheel base trucks, at least on the Extra cabs. I think the longbeds had 1-piece shafts. Here's a writeup on the conversion process.