Rear Drive Shaft Length?

Installed my rear drive shaft... I think it is too long. I was able to get it in, however I have no more "collapse" on the drive shaft. Here are the specifics

'67 CJ6, V6 with T90, D18 xfer case (the single shift has been replaced with a double shift Xfer case). Stock D44 in the rear. Stock Springs and lift. I had the springs cleaned up and "re-arched". they look OK and shocks fit fine.

The parts book calls for a shaft that is 40.94" long "Collapsed length is from center to center of end yoke". I assume that means center to center of the two spiders. Mine measures 38.5" when installed.

Suggestions?

 

A driveshaft shop can shorten it for very small money.

 

x2 on driveshaft shop . you just give them the center to center . and they will shorten shaft with proper slip joint travel

 

Thanks, I may have to do that. I would like to figure out why it doesn't fit. How much travel (in and out) should I have on the drive shaft?

 

I am confused!! Your D-shaft is already 2 plus inches shorter than parts book spec? Your T-90 is same length as factory original T-86AA (used with 225) and the D-18 is correct so the way I see it your shaft should work? Re-arching the springs would give you even a little more distance between couplings.

 

Yea, I am stumped to. It should work. I am measuring from the center of the spider to the center of the spider. I just re-measured the center to center of spider and it is right at 39" Not the 38.5" I reported yesterday (don't know where I got that number). I assume when the parts book says " "Collapsed length is from center to center of end yoke" that is what they mean. The overall length from D18 e-brake drum face of the yoke to the center of the spider on the D44 is 40.5".

Anyway it is shorter than the book calls, but it is too long.

 

Where did the shaft come from that you are trying to use? Is it original, new, or???

Are you sure that spec was for the rear shaft? Is your manual OEM "factory" (not generic aftermarket publisher)?

 

The shaft came on the Jeep. Assume original, but the PO did make other modifications. The entire drive train was taken apart I rebuilt the transmission and put it back together with new u-joints. Don't remember this problem when I took it apart but wasn't paying attention. Didn't drive the jeep prior to disassembly as the transmission had rusty water in the bottom and dust in the top.

Yes rear. It is an OEM parts book.

 

T86 shaft would be 38.37, collapsed, c to c on the yoke u-joint hole opening
T14 would be 37.37.

You'll need at least 2.5 inches minimum of slip yoke movement in my opinion.
Rear leaf springs in backwards?
All else fails, just measure what you need and have yours modified.

 

Thanks for the dimensions. Not sure what you mean by "Rear leaf springs in backwards?" These springs are symmetrical. I measured the springs and they are 45" center of eye to center of eye. The FMS says should be 46 1/8" so that may be part of the problem.

May have to modify, will check into that today.

 

OK it is done. Had the drive shaft shortened. Easy Peasy.

 

About how much did it cost to be shortened? are we talking 20-50 bucks or 200-300?

 

"Rear leaf springs in backwards?"

Most vehicles with leaf springs have the centering holes off-set to where the pins on the axles will position the axle at 40% of the length of the axle from the leading end of the spring set.
That would only make the driveshaft longer, though. Not shorter like yours is.

 

Not if the springs were installed backwards like was mentioned.

 

Nick, read post 10 again. The 1 1/8 difference in spring length would add to the problem. It reads like there is a bit more involved and I have to say I have no idea, it's pretty hard to diagnose using a computor rather than getting greasy laying there under the Jeep with a tape measure.

 

$85 which included balancing.

 

The shaft came out 38 3/16", collapsed. The measurement from where it bolts up to the e-brake on the back of the D18 to center of D44 yoke was 40 1/5".