Driveshaft Question

[Scott B.]

I am going to rebuild or replace the 2-piece driveshaft on my '93 Ranger. It has 304K miles on it - probably about time!

The question is, rebuild or just replace. By rebuild, I mean cut out and replace the slip joint, the u-joints (3) and carrier bearing, and balance.

How much of a difference does it make if each shaft is balanced individually as opposed to together (with u-joints installed)?

For the record, I have replaced u-joints and carrier bearing at 100K and 200K miles without re-balancing the shaft.

 

[Scott B.]

Part B -

If I replace the driveshaft (or the long half with the slip joint,) who builds a good one?

 

[glfredrick]

I noticed that you didn't get a response to your question.

A lot of people advocate getting rid of the two-piece driveshaft on the long wheelbase rangers. I do also - but I replace it with a stronger/better design.

I copied this idea from a guy on Rough Rangers.

Check out this picture:

That is two Explorer rear driveshafts run back-to-back through an industrial pillow block bearing. They do need to be shortened, but that is relatively inexpensive compared to building an entire new driveshaft.

Yeah, that is two explorer rear 1310 shafts shortened and facing each other. All the explorer slips that I have are 1.875 diameter (after a flap wheel cleans the rust off). I bought a 1 7/8" pillowblock for $30 at Fastenal and the slip is a light tap fit. Both rear driveshafts ended up the same length.

...

This is an excellent modification, for a long wheelbase rig. It is tried and tested, easy to find junkyard shafts to modify, and cheap. It is kind of funny, because one of the first "upgrades" I did to my rig was remove the carrier bearing and crossmember and go with a looong shaft. That solved the problem with the factory weak carrier bearing vibes, famous in an extended cab truck, and made it a better daily driver. But, not the ideal solution for a trail truck that was going to see some heavy big rock action underneath. I am thoroughly happy with the results here, costing roughly $30 for a bearing, some scrap steel I already had, and a couple explorer shafts I already had laying around. It is way simpler than some of the other conglomerations I have seen posted out on the web.

The bearing rides right on one of the yokes. Just polish it up some to fit the 1.875" (1 7/8") bearing.

This setup holds the driveshaft up high in the chassis, out of the way of rocks and such, and it will also allow for a rear anti-wrap bar (or like the original builder, a 4 link) that is not absurdly long.

Pillow block bearing is available from Fastenall:
http://www.fastenal.com/web/products/detail.ex?sku=0474602&ucst=t

This is probably an "off-road only" sort of a modification, but the OP says that he has wound it out to 6000 rpm on the street and it worked.
http://www.rrorc.com/gallery/data/622/14_bolt_014_small.JPG

 

[RockRanger]

That shaft idea is sweet. I will have to remember that for a 2pcs front shaft I will need someday.

To the original poster any local shaft should be able to do it. I would replace it with a 1 piece though. I heard that 98 up rangers have one piece factory shafts that bolt right in. Do not quote me for sure on that though.

 

[Scott B.]

RockRanger - yes, '98 and up have one-piece shafts. My '06 has an aluminum one-piece - I think the older ones were steel.

glfredrick - that looks like a really good idea. My only concern is my truck is driven not trailered - I wonder how that would hold up driving across the country?

And a question - by how much does the shorter rear shaft increase your u-joint angle? I assume for rock crawling, getting the shaft up, out of the way is worth the trade-off of increased angle.

 

[glfredrick]

RockRanger - yes, '98 and up have one-piece shafts. My '06 has an aluminum one-piece - I think the older ones were steel.

glfredrick - that looks like a really good idea. My only concern is my truck is driven not trailered - I wonder how that would hold up driving across the country?

And a question - by how much does the shorter rear shaft increase your u-joint angle? I assume for rock crawling, getting the shaft up, out of the way is worth the trade-off of increased angle.

The biggest problem with the off-road truck and the one-piece is the fact that it hangs so low, and is so long, that it is constantly getting bashed if one wheels in any sort of rock garden trail.

I don't know how that setup would work on a long-distance jaunt. I suspect that it may be prone to vibration at steady freeway speeds, but it wouldn't have to vibrate. If everything was accurate, angles right, and shafts balanced, I'd think that it would run as good as any other setup -- and perhaps better than the factory. About the only difference is the fact that the pillow block is solid instead of rubber mounted like factory pieces, and you could substitute a rubber mount -- they exist -- but cost is double. I like the simple indestrubtability of the setup, which is why I'm going that route.

I don't think that u-joint angles are that bad, but both the original poster of that setup and myself are running custom hung rear axles where we've turned the joint up some. The big deal is to balance the u-joints, so that each is on the same plane. That cancels out vibration. Neither shaft is that short anyway, and as built in the pictures, both are the same length. They each also have a slip yoke.

 

[RockRanger]

Off road I wouldn't worry to much about it. For what it is worth I have my rear pinion pointed about 10 degrees higher then it should. Just so I keep the driveshaft out of the rocks. My truck gets trailered mostly. I would run a thickwalled rear driveline and be done with it. My 86 ranger had a 1/4" thick wall rear driveline on it. I had rock scratches going all the way down it. It stayed strait. Ask DB1 about thin walled rear drivelines. 2 trips 2 dented rear drivelines.