Going to a one Piece Driveline

[Piper71c10]

What's involved? Is there an easy swap out there? would I have to modify my crossmember?

Thanks guys
Piper

[Randy70C-10]

You won't need that crossmember anymore. Also, make sure that you have the new shaft balanced, it will be long and will definately need to be balanced!

[Piper71c10]

What about the stabilizer bars? They bolt to that crossmember as well.

Piper

[tom hand]

I think you really need that crossmember...lol. I have gone to a one piece on a slightly lowered swb and had no problems with it hitting thru the stock hole

[Piper71c10]

Anyone remember the measurement for a one piece? Wondering if something out of a '73-87 won't work.

Piper!

[rickspickuppart]

have one made, and depending on how low the truck is you might have to trim some of the crossmember

[Randy70C-10]

Oops, sorry about that....(I have a leaf-spring rear) Yes, you should keep the crossmember. lol

[mocwon]

So, Randy I have a 72 short bed that I converted from trailing arms to leafs; are you saying I can take that cross member out that held the bearing for the two piece driveshaft if I go to a one piece driveshaft? Thanks

[crazy longhorn]

the factory had that crossmember in the truck on the leaf versions......you could take it out &probably not cause any trouble on a "driver". If its not in the way, & you like to "crank it up", the more crossmembers the stiffer the frame will be. it just depends on useage....crazyL

[Longhorn Man]

Are you looking to instal one on a SWB, or a LWB truck?
Shorties came stock with a one piece. (some did...not all)
If it is a long wheel base truck, expect to pay quite a bit of cash for this. Once you hit 6 feet in length, most shops will send you away. Only let the best places build a shaft over 6 foot in length, and see if they weill repair it if they goof it up and it whips at freeway speed. (freeway speed deifined as 100 MPH or so)

[Randy70C-10]

I have a one piece shaft on my longbed, but I don't know where it came from. It was there when I bought the truck. It works great, but on a very bumpy road the the driveshaft will tap the crossmember a little. I'm going to remove it when I get a chance.

[SLS]

Randy,

I have a one piece in my '71 SWB and the same thing happened to mine. Except it dinged it up enough to cause quite a vibration...yikes! Has yours gotten dinged up at all???

Apparently, when the PO swapped the engine and trans in my truck, he also swapped the shaft...which was a 3" OD (and thus didn't have enough travel/clearance at the crossmember). It was very 'tight' and you could hear it 'ping' sometimes just dropping it into 'drive' (and 'reverse')....ARRRGGGGHHHH!!!!!!!!!!

Here's the thread (which piper may find useful too):

http://67-72chevytrucks.com/vboard/s...threadid=67673


If I had a longbed I would probably go with the 2 piece setup....after discussing driveshaft workings, travel, ect. with my driveline guy. He said anything over 6" is "tricky" when it come to single-unit shafts. "Whip", and clearance, seems to be the issue, according to him anyway........

[Longhorn Man]

Besides, I have seen trucks running 12's in the 1/4 mile with a stock 2 piece drive shaft. If it can handle that, I doubt there is much it wouldn't handle. (You are't trying to go 10 flat in the 1/4 are you?)
Just replace the carrier, and the 3 U-joins, and keep everything lubed. It'll hold up for years if done properly. (Sealed U-joints are stronger, and I have seen plenty of them go well over 100,000 miles)

[crazy longhorn]

I have been looking at the 1 pc route on the longhorn, & a little measure says 73" c to c on the caps will get it.......I havent found a shop that will touch it , considering that the engine will pull 6500 rpms in 5th gear. Thats spinning the snot out of that shaft! From a little reading, I think a carbon fiber shaft would do fine at the lenght, but ZOWIE......they arent cheap! i need to upgrade to the 1350 u joints, & have a new shaft set up but im not sure that I will get around that 2 pc setup. I am not running slicks, but that 383 & 6spd combo is pretty brutal on driveline parts. any thoughts about a large diameter aluminum shaft? crazyL

[Maximum Overdrive]

Originally posted by Randy70C-10
I have a one piece shaft on my longbed, but I don't know where it came from. It was there when I bought the truck. It works great, but on a very bumpy road the the driveshaft will tap the crossmember a little. I'm going to remove it when I get a chance.

Better watch it. I had a one piece in a 69GMC with leafs and I hit a bump doing about 90 mph down the Interstate. Anyway the driveline busted and slammed into the bottom of the cab. It hit the cab and sounded like a bomb going off. Put a huge rise into the cab floor where the console goes. It also busted the driveline into a couple of pieces, busted the tailshaft off the transmission, busted the transmission casing off the engine and busted a chunk off the rear end housing where the driveline bolted onto the rear end.

[68 Stepside]

One thing that always concerned me about removing the crossmember is that you won't have any protection if you drop a front u-joint. There's always that possibility that you could be doing cartwheels down the road if you did in fact lose the front u-joint. Kinda scares me. I guess if you did remove it, at least run a set of driveshaft loops. I dunno, maybe I'm just anal about things, and worry too much

[Piper71c10]

Thx for the thread SLS. I sure would hate to be driving down the street clenching my butt everytime the shaft ding'ed against the crossmember. SCARY!

Piper!

[Canada20]

Crazy: I saw some CF driveshafts online; how do you think they'd hold upon a daily driver. The company that makes them claims they're the best thing ever.

What's the advantage of 1pc vs 2pc driveshafts?

Greg

[crazy longhorn]

I dont have too much info on the carbon fiber shafts. from what I understand, they will handle more shaft lenght & not have the problems that the steel shafts have(whip in the center). They are also said to be very smooth, as they remove the harmonics that are annoying & damaging. The other thing I was told is that they will flat shread as a result of component failure....nothing but shreads & powder! On one hand that is good, you lose a u joint, & the shaft doesnt "endo" the truck. they arent reccomended for transbrake or stick shift apps in racing from what I understand. I would like to hear a little more info on the subject, as those shafts are a lot of cash! (pretty hard to explain to the wifey that the shreads & powder on the garage floor WAS my $1000 D shaft ) yesterday was "boneyard day".....i have done this before, in search of a factory shaft in the proper lenght(or close enough to cut) for my 69. The longhorn, even with the eng set back will take a 73" long shaft C to C on the caps.......I'll be damned if i can find on that is any longer that 70 1/2" in a 1 pc. an aluminum shaft is 5" diameter @ that lenght! Most of the shops I have talked with do not want to do beyond 58-60" on a 1 pc shaft.........my guess is that there is a good reason for that Unless i get some better info on the carbon fiber shafts, I will be running a custom 2 pc with 1350 joints.....crazyL

[jover]

we have a 68 stepside, we had a one piece made for it, 4" diameter, went right through the crossmember hole just fine, really was a simple to put on.