One Peice Drive Shhaft vs Two Peice

JOHNBOY

ZF6 Sled Puller
Joined
Feb 1, 2007
Messages
1,854
Ok I been pondering this one. My truck. A Crew Cab longed has a steel two peice driveshaft. I never had any trouble with it or the carrier bearing. But I am getting a major increase in power output.:st:

I have heard that one peice is better. Is this true? How long can you go? My stock shaft measures 88" form joint to joint. That seems a tad long for one peice to me.

Oh a little insight for those that have not seen me hook. This is a manual trans truck and I usaully roll out at over over 4000rpm+. Sometimes I just wait till the frame stops hit and letter eat.:rockwoot:
 
JohnBoy I had both. I had a one piece, but the driveshaft guy said that he didn't recommend it on the street. I never had any issues, but I went back to a two piece. I have the international carrier bearing and all 1480 u joints in the set up. So far no issues at all. What does your local driveshaft shop say? I think greensburg machine makes driveshafts and they are over in PA.
 
the thing about a once piece is you can only have so much articulation... if this is a sled truck with stiff rear suspension, you should be fine w/ a 1 piece
 
Driveshaft speed is also an issue. The longer the shaft the more of a tendancy for it to deform under high speeds, and once it starts to deform it behaves like a jump rope! Talk to cooper about this, I am sure he has some equation that can make a recommendation. The driveshaft guy I used said for high speeds I would be better off with a 3" two piece. For low speeds use a 4 inch tube. I opted for a two piece 4 inch tube.
 
Makes sense.

I am 3.5" inch right know with 1480 joints. I guess I should look into upgrading my carrier bearing.
 
I don't think the carrier bearing really needs the upgrade, just the u joint up by the carrier bearing. We all know a DMAX can't make enough power to tear anything up! :)
 
zstroken said:
I don't think the carrier bearing really needs the upgrade, just the u joint up by the carrier bearing. We all know a DMAX can't make enough power to tear anything up! :)

Well at least not mine!LOL
 
I run the factory dudge 2 piece and it works great. Has 3 1480's and is about 4" in diameter and my truck makes an honest 500rwhp.
 
JOHNBOY said:
Makes sense.

I am 3.5" inch right know with 1480 joints. I guess I should look into upgrading my carrier bearing.

One thing you will want to check is the amount of grease that's in your center splines and yoke. GM got skimpy and didnt use enough. My truck had the proverbial jerking action when rolling really slow. Felt just like the ABS was acting up but it was actually the rear driveshaft sticking in the center yoke because there wasnt enough grease.
 
JW3 said:
I run the factory dudge 2 piece and it works great. Has 3 1480's and is about 4" in diameter and my truck makes an honest 500rwhp.

Thanks Justin. I think you make a little more than 500rwhp.:rockwoot:

I think my stocker will be fine as long as I take good care of it with Spicers joints and keep grease in the slip.

PS I should make a little more than 500.:evil
 
I dunno JB.

After I ran dang near the whole season on my 4" dia. x 80.5" long steel one-piece, Mark from Greensburg Machine comes up to me and says, "I just cringe every time you pull!" Thanks, Mark!

Anywho, he said he'd build me a puller-only heavy wall piece that is NOT for the road. Maybe he'd do the same for you. A few of the RWYB trucks should have really long driveshafts, so he should know. And since yours is gonna be ridin' a trailer like mine, I'd say go with a single.

I'd bet money that you're going to be OK with a 2-piece until some pull where you get to hopping, and then it's going to throw it right out. I hope I'm wrong, but you're in kinda new territory with everything you're doing. Why add drivetrain to the list?

If your truck tosses it, it's gonna be uuuug-leee.
 
Last edited:
Lenght?

One thing you might want to watch out for, which I may have skipped over in the previous posts, is lenght. If you are looking to run a street class or ever on the street but a 71in lenght is all the more that is legal on the street. Though very few people know that, I figured I'd throw it out just in case.
 
mines 82 long 1480 joints on both ends 4inch diameter, driven daily only issues is 70-75mph is top speed its starts a good vibartion around then
 
Like I said, not many people know it. Heck, I had guys at the inspection station have no clue about it. I got to find the page it is on in the PA Inspection book but I was told about it by an old professor and when I went to a place in PA that could buld me one, they wouldn't go over that lenght and I needed a 73in one. So, that means I went looking else where.
 
edited....my bad...sorry...

The Chevy CC/SBs all come factory with 70.5" aluminum shaft.

The old gasser Chevies had 68" or so (so Mark told me) so that's why we didn't worry about 70" (and went bigger dia. to do it).

You might be right!
 
Last edited:
Drive Shafts

Critical Speed is what your looking for. That long I would stick with your 2 piece shaft. Very strong! You do not run enough SPEED to worry about the 2 piece. Look at any big truck and see what they have. They need to be strong with a heavy load at a fairly low speed.
 
My only thing would be, if that carrier bearing and whatever it's mounted to moves, deflects, etc., it could all try to pretzel.

The stock system was designed for 300 hp and 520 tq. John should be pushing at least 2X that, if not 3X that.

Who knows? Like I said, seems like new territory. Do any of the ex-cab Dodges with big HP run a 2-piecer?
 
I added just 1480 joint to my stock driveline, then carrier bearings started going like flys after that, b4 i was knocking u joints out, so then i went to a single and no problems since, thats comming out of the hole at 4krpm and 40psi
 
nwpadmax said:
My only thing would be, if that carrier bearing and whatever it's mounted to moves, deflects, etc., it could all try to pretzel.

The stock system was designed for 300 hp and 520 tq. John should be pushing at least 2X that, if not 3X that.

Who knows? Like I said, seems like new territory. Do any of the ex-cab Dodges with big HP run a 2-piecer?

Define big HP. I have ran a 2 piece all year, no issues. I have a large carrier bearing. I came from a HD one piece, but the guy who built my driveshaft said it was too long for the road. This is the same guy that builds haisleys and scheids driveshafts in the mods! So far the 2 piece has been great. 3000 RPM lauches at 25-30 psi. FYI though my truck never seems to bounce though.
 
nwpadmax said:
My only thing would be, if that carrier bearing and whatever it's mounted to moves, deflects, etc., it could all try to pretzel.

The stock system was designed for 300 hp and 520 tq. John should be pushing at least 2X that, if not 3X that.

Who knows? Like I said, seems like new territory. Do any of the ex-cab Dodges with big HP run a 2-piecer?

Mat you and Dan (zstroken) brought some great points. I crawled under the old schooler and took a look. The cross member that the carrier bearing bolts to is pretty weak looking. I been thinking about pulling the bed when I build the hitch I think that I should beef the cross member also. The stock carrier bearing is in a plastic support held on to the cross member with a big metal U strap.

Right now I am thinking that I should get the stock shafts retubed to beefier tubing. Replace carrier bearing with a more robust unit. Weld some trianlgulated (sp?) supports to steady the flimsy cross member. With the bed off it would be easier to fab the sheilds and loops. This pulling the bed stuff is sounding better and better.:bang


OT anybody know of the part number or if Spicer makes one those new super strong Forged U-joints in 1480? Anybody heard of a spool and larger axles yet? 40 spline would rock.
 
Last edited:
Back
Top