So let's talk drive shafts

[dremu]

Yeah, I know, the answer is "Call Jesse" ... but I wanna understand what I'm talking about when I do call, and besides, it's late

So, first up, is this thing on my factory '74 front shaft a double cardan joint? (see pic) If not, what is it? CV joint?

Second thing is travel. My factory rear shaft seems to have a whopping great 1.5" of travel, and the front more like 3.5" Is there something seriously wrong with this picture? Seems like the rear would need more travel as it's longer ... yeah?

-- A

 

[jekbrown]

the rear doesn't need very much travel at all... because as the suspension droops and the shackle rotates, the axle is moving closer to the tcase (in the horizontal plane). Compare that with the front end, where the axle is moving further away in both the horizontal and the vertical planes.

anyway, there is a driveline tech article on pirate if you really want to know all the subtle stuff and technical names for things. I just went with HAD.

j

 

[dremu]

the rear doesn't need very much travel at all... because as the suspension droops and the shackle rotates, the axle is moving closer to the tcase (in the horizontal plane). Compare that with the front end, where the axle is moving further away in both the horizontal and the vertical planes.

anyway, there is a driveline tech article on pirate if you really want to know all the subtle stuff and technical names for things. I just went with HAD.

j

ah yes, and the front axle is offset to the side, and the rear is centered. I shoulda gone to Billavista first

-- A

 

[dyeager535]

Not to drag this out, but the factory '91 front shaft I have has only about 1.5", while the rear is easily double that.

The front shaft has so little travel/margin of error that I'm taking the truck down to the driveline shop when I have the front shortened, so there can be no ($45) excuse to not get it the right length the first time.

 

[dremu]

Not to drag this out, but the factory '91 front shaft I have has only about 1.5", while the rear is easily double that.

The front shaft has so little travel/margin of error that I'm taking the truck down to the driveline shop when I have the front shortened, so there can be no ($45) excuse to not get it the right length the first time.

That is pretty close.

What's the $45, their charge to measure, or the retube?

-- A

 

[dyeager535]

$45 to shorten, double that if balanced.

3.5" of travel on the stock rear, just measured. The front shaft that came with the rear (probably '74) has about 2" of travel.

 

[sweetk30]

$45 to shorten, double that if balanced.

what ? my shop will shorten and balence for 50 bucks. and thay will reman my frt shafts with 3 new spicer joints and a spring and ball kit with labor for 85 bucks. all this out the door plus tax also.

 

[dyeager535]

"horseheads,ny Land Of Crapy Economy"