swapped my rear driveshaft to a single piece

fastr68 · 11-21-2008, 09:47 PM

so today i put the one piece driveshaft under the rear of my longbed 2wd today

yesterday i cut 1.5" from the shaft to shorten it that much so it was what i needed to use under the truck.

it is actually pretty easy to shorten a driveshaft.

i used a grinder to grind down the weld until i could see a hairline crack,
i went all the way around it with the grinder and when enough was removed the yoke simply fell off the end of the driveshaft tube

then i clamped a hose clamp around the tube where i needed to cut it and i used a thin cutting wheel on an air die grinder

rat tail filed the inside diameter of the tube and beat the yoke into the tube pretty good and used a 220v stick welder with a 6011 rod and welded it three passes

truck is smooth as glass now! no more crappy vibration or shaking from the junk 2 piece shaft setup yay!

for a longbed standard cab 2wd it is 66.5" from end of tranny tail back to the axle pinion yoke

i used a driveshaft from a 90 conversion van they use even the same u joints as the s-series trucks

any questions lemme know

Golana · 11-22-2008, 12:06 AM

sounds awesome man. i have a ext. cab... would this be useful to me? im in the process of bagging my truck... would it be more in my best interests to stick with a 2pc driveshaft, or go a 1pc?

***fetuss10*** · 11-22-2008, 02:00 AM

Good Stuff. I'm going to sticky This.

pack of q tips · 11-22-2008, 02:20 AM

ehhh i would be wary of doing this yourself
driveshafts need to be balanced and uneven welding could throw it out

Golana · 11-22-2008, 09:34 AM

Quote: Originally Posted by pack of q tips

ehhh i would be wary of doing this yourself
driveshafts need to be balanced and uneven welding could throw it out

he said there's no vibration... if there's no vibration, then its obviously balanced...

AK99 · 11-22-2008, 10:49 AM

Quote: Originally Posted by Golana

he said there's no vibration... if there's no vibration, then its obviously balanced...

He's just good... or very lucky. It doesn't take much at all to throw a shaft out of balance.

fastr68 · 11-22-2008, 07:06 PM

Quote: Originally Posted by Golana

sounds awesome man. i have a ext. cab... would this be useful to me? im in the process of bagging my truck... would it be more in my best interests to stick with a 2pc driveshaft, or go a 1pc?

depends on length

cant go over 74"from tail endof tranny back to the pinion yoke with a one piece

if 74 or less distance then yeah

if you have no problems with the current shaft setup then you wouldnt really need to convert to single shaft unless you needed alot of angle change in your driveline with the suspension modifications you are doing

the single shaft can change angle alot further than the two piece due to the fixed carrier in the center like that

IMHO

good luck

fastr68 · 11-22-2008, 07:09 PM

Quote: Originally Posted by pack of q tips

ehhh i would be wary of doing this yourself
driveshafts need to be balanced and uneven welding could throw it out

ppl are too scared of things like this

its no big deal

as long as you are carefule not to change anthing other than the length then its fine

in my case all i did was remove a measly 1.5" from the length

very simple

luck is nothing do with it

as long as you weld the yoke back on lined up with the yoke on the other end of the shaft then youre fine

mines doing perfect, smooth like new, awesome =)

what happened to my two piece driveline was that the u joints froze and it caused the shaft to bind up and it became out of round or twisted and un repairable

had a really bad shimmy shake in it around 30mph and when i loaded weight on the rear the entire truck would violently severely jump hop and i couldnt go over 10mph or i couldnt hold the steering wheel any longer

like a brand new truck now

anything else lemme know

jtcfanof3 · 11-22-2008, 07:30 PM

Golana,I think if you swaped too a 1 peice shaft,you may lose out on how low you can go when you bag it,the center bearing acts like as if thats where the tail shaft would be,this allows a more centered fulcrum when laying out in the back,if you have a 1 piece shaft most likelly your gonna hit the bottom of the cab before you get layed out.

88chevys10 · 11-25-2008, 10:35 PM

I did this exact same thing last year. I used a chop saw instead, but as well no vibrations. Took off a couple inches because of my v8 swap. I have a long bed. We had to move the carrier bearing back and shorten the back driveshaft. Spent about 8 hours doing it, but made real sure. One thing. Make sure you use a dial indicator. And before making the final weld on the driveshaft but it in there and run that to make it as true as possible. It it needs some adjusting smack it at the yoke with a hammer and try again. Once as true as you can get it. Make the final weld.

cheseburger · 01-19-2009, 01:54 PM

The biggest reason trucks go to a 2 piece drive shaft. Longer than 55inches the shaft will cease to rotate true and will start to ocilate out of round. Usually at high speed or at 70mph or higher. It wears out berrings and if it were to come apart front piece can wedge into asphalt flipping truck. Rarely seen it , uaually at track with high torque appl.

chucke2009 · 01-23-2009, 10:37 PM

real neat prank-i know its random, but stick a zip tie around someones driveshaft. Once they get going it starts to hit the car body and it sounds like the thing is fallling apart. Breaks off after about a mile or so :-)

jarrodh · 02-21-2009, 03:21 AM

Quote: Originally Posted by cheseburger

The biggest reason trucks go to a 2 piece drive shaft. Longer than 55inches the shaft will cease to rotate true and will start to ocilate out of round. Usually at high speed or at 70mph or higher. It wears out berrings and if it were to come apart front piece can wedge into asphalt flipping truck. Rarely seen it , uaually at track with high torque appl.

wasnt on a truck, but saw it happen on a friends 66? comet a year or 2 ago on the 1/4 mile.. it either the driveshaft boke, and did just that, or it was a leaf or traction bar broke, and pole vaulted his car, and it hapeened right the finish.. nearly killed him..

and yes ive herd that a long drive shaft can start to "whip" and shatter..all kinds of fun at speed..

SH-60B · 02-25-2009, 02:16 PM

Quote: Originally Posted by cheseburger

The biggest reason trucks go to a 2 piece drive shaft. Longer than 55inches the shaft will cease to rotate true and will start to ocilate out of round. Usually at high speed or at 70mph or higher. It wears out berrings and if it were to come apart front piece can wedge into asphalt flipping truck. Rarely seen it , uaually at track with high torque appl.

The driveshaft didn't "ocilate out of round" in the van he got it out of, why would it in his pickup? MPH has little to do with driveshaft RPM, the rear end gear will dictate shaft rpm at a given speed. The shaft is spinning a lot faster with a 4.11 gear than a 2.73 gear.

david gmc · 03-17-2009, 02:37 PM

will a driveshaft outta an astro wrk in an s15???

fastr68 · 03-21-2009, 05:33 PM

Quote: Originally Posted by david gmc

will a driveshaft outta an astro wrk in an s15???

hi there

hmm, well as far as what ?

length? probably not.
get the tape measure out

but if its a hair longer then it can be cut down and used for sure

----------

74" from tail end of the tranny back to the pinion yoke is the longest ive seen in stock form for a one piece shaft and that is under the 73-up 2wd full size trucks

very common

-------

its been many monts now since i cut and put mine in from the van and its doing perfect, truck is still smooth as silk going down the road all the vibrations and such have been totally gone, not even any hint of vibration in the steering wheel anymore either since i did this

i drive this truck every day and alot and i couldnt ask for a better running driving truck especially at 196k miles now.

heres a couple pics i took a minute ago, i see that my shaft has rubbed the carrier bearing crossmember a few times ahaha i need to do something about that apparently lol

im shortening the driveshaft under the 78 c-10 pickup i recently acquired so i can go from the toasted original th350 to a 3L80HD from an 87 pickup in which is 3" longer than the th350

ive already cut it and cleaned it up, ready to weld the yoke on real soon

i may take pics, if i remember to grab the camera, like i meant to when i did the van shaft.

88GMCs-15 · 05-23-2009, 02:53 PM

Quote: Originally Posted by fastr68

ppl are too scared of things like this

its no big deal

as long as you are carefule not to change anthing other than the length then its fine

in my case all i did was remove a measly 1.5" from the length

very simple

luck is nothing do with it

as long as you weld the yoke back on lined up with the yoke on the other end of the shaft then youre fine

mines doing perfect, smooth like new, awesome =)

what happened to my two piece driveline was that the u joints froze and it caused the shaft to bind up and it became out of round or twisted and un repairable

had a really bad shimmy shake in it around 30mph and when i loaded weight on the rear the entire truck would violently severely jump hop and i couldnt go over 10mph or i couldnt hold the steering wheel any longer

like a brand new truck now

anything else lemme know

my front yoke coming out of the ass end of the tranny siezed up and course the front driveshaft was still turned so it tore up the u-joint in my ford ranger.. i was dropped the front end into a little mud hole and was trying to pull out of it and snap... and of course got stuck in 2wd so i had to get a couple quads to pull me out.

the_s15_virgin · 06-30-2009, 12:02 AM

Can anyone give me an idea on a drive shaft to fit my 86 gmc s15 with a 82 2.8 v6 and 4 speed manual transmission swap? Anyone done this?

Patriotslist · 07-07-2009, 01:11 AM

Drove a tow truck for 18 years. This made me think of a tow I once did.

Did a call once where a guy did something similar with an old truck he did this with for some reason to lose the carrier bearing cuz it kept chewing them up and vibrating. The cross member where the carrier used to mount was in the way for the solid shaft "he made" so he torched it out.

He was driving the truck down the hwy towards laughlin near the river run time of year and the front of the shaft broke where he welded it. Shaft went under the trucks back tire and it rolled into the dry lake bed. I only saw it afterwards of course but I envisioned a "catapult" scenario, hehe. His shit was scattered for about 500 feet, swept the highway for about an hour. He didn't get hurt luckily.

I'm sure this ones fine, not trying to make you paranoid. Thought you might find it interesting or at least get a chuckle out of it.

fastr68 · 10-16-2009, 03:33 PM

even after all this time having swapped to a one piece shaft, i am curious as to why all these 118" WB trucks have a two piece driveline.

the longest factory made one piece GM driveline i know of is under the full size trucks 73-up and they are 74" from the tail of the trans back to the pinion yoke. with the th350 9" tail and the 700r4 trans

the 118" WB s-series tail to yoke distance is less than the full size trucks i know,

so i just wonder...

hmm..

fastr68 · 10-16-2009, 03:36 PM

Quote: Originally Posted by the_s15_virgin

Can anyone give me an idea on a drive shaft to fit my 86 gmc s15 with a 82 2.8 v6 and 4 speed manual transmission swap? Anyone done this?

tape measure

and junk yard hunting

look for one the same distance from trans tail back to the pinion yoke

or one just about an inch more than this and have it cut

yours could be 108" or 118" WB or ext cab WB even

each has its own dshaft length

the full size van one happens to be a hair longer than the 118" WB s-series and works out good

11-21-2008, 09:47 PM	#1
fastr68 easterwabbit Join Date: Sep 2002 Posts: 597 Location: Lincoln, IL User is: OffLine	swapped my rear driveshaft to a single piece so today i put the one piece driveshaft under the rear of my longbed 2wd today yesterday i cut 1.5" from the shaft to shorten it that much so it was what i needed to use under the truck. it is actually pretty easy to shorten a driveshaft. i used a grinder to grind down the weld until i could see a hairline crack, i went all the way around it with the grinder and when enough was removed the yoke simply fell off the end of the driveshaft tube then i clamped a hose clamp around the tube where i needed to cut it and i used a thin cutting wheel on an air die grinder rat tail filed the inside diameter of the tube and beat the yoke into the tube pretty good and used a 220v stick welder with a 6011 rod and welded it three passes truck is smooth as glass now! no more crappy vibration or shaking from the junk 2 piece shaft setup yay! for a longbed standard cab 2wd it is 66.5" from end of tranny tail back to the axle pinion yoke i used a driveshaft from a 90 conversion van they use even the same u joints as the s-series trucks any questions lemme know Last edited by fastr68 : 11-21-2008 at 09:48 PM.
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11-22-2008, 12:06 AM	#2
Golana Truck #121616 Age: 23 Join Date: Jan 2007 Posts: 2,800 Location: High River, Alberta User is: OffLine	Re: swapped my rear driveshaft to a single piece sounds awesome man. i have a ext. cab... would this be useful to me? im in the process of bagging my truck... would it be more in my best interests to stick with a 2pc driveshaft, or go a 1pc?
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11-22-2008, 02:20 AM	#4
pack of q tips Founding member of DA Age: 27 Join Date: Nov 2002 Posts: 3,984 Location: massachusetts User is: OffLine	Re: swapped my rear driveshaft to a single piece ehhh i would be wary of doing this yourself driveshafts need to be balanced and uneven welding could throw it out
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11-22-2008, 09:34 AM	#5
Golana Truck #121616 Age: 23 Join Date: Jan 2007 Posts: 2,800 Location: High River, Alberta User is: OffLine	Re: swapped my rear driveshaft to a single piece Quote: Originally Posted by pack of q tips ehhh i would be wary of doing this yourself driveshafts need to be balanced and uneven welding could throw it out he said there's no vibration... if there's no vibration, then its obviously balanced...
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11-22-2008, 10:49 AM	#6
AK99 Registered User Age: 27 Join Date: Oct 2008 Posts: 103 Location: West Jefferson, OH User is: OffLine	Re: swapped my rear driveshaft to a single piece Quote: Originally Posted by Golana he said there's no vibration... if there's no vibration, then its obviously balanced... He's just good... or very lucky. It doesn't take much at all to throw a shaft out of balance.
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11-22-2008, 07:06 PM	#7
fastr68 easterwabbit Join Date: Sep 2002 Posts: 597 Location: Lincoln, IL User is: OffLine	Re: swapped my rear driveshaft to a single piece Quote: Originally Posted by Golana sounds awesome man. i have a ext. cab... would this be useful to me? im in the process of bagging my truck... would it be more in my best interests to stick with a 2pc driveshaft, or go a 1pc? depends on length cant go over 74"from tail endof tranny back to the pinion yoke with a one piece if 74 or less distance then yeah if you have no problems with the current shaft setup then you wouldnt really need to convert to single shaft unless you needed alot of angle change in your driveline with the suspension modifications you are doing the single shaft can change angle alot further than the two piece due to the fixed carrier in the center like that IMHO good luck
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11-22-2008, 07:09 PM	#8
fastr68 easterwabbit Join Date: Sep 2002 Posts: 597 Location: Lincoln, IL User is: OffLine	Re: swapped my rear driveshaft to a single piece Quote: Originally Posted by pack of q tips ehhh i would be wary of doing this yourself driveshafts need to be balanced and uneven welding could throw it out ppl are too scared of things like this its no big deal as long as you are carefule not to change anthing other than the length then its fine in my case all i did was remove a measly 1.5" from the length very simple luck is nothing do with it as long as you weld the yoke back on lined up with the yoke on the other end of the shaft then youre fine mines doing perfect, smooth like new, awesome =) what happened to my two piece driveline was that the u joints froze and it caused the shaft to bind up and it became out of round or twisted and un repairable had a really bad shimmy shake in it around 30mph and when i loaded weight on the rear the entire truck would violently severely jump hop and i couldnt go over 10mph or i couldnt hold the steering wheel any longer like a brand new truck now anything else lemme know Last edited by fastr68 : 11-22-2008 at 07:18 PM.
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11-22-2008, 07:30 PM	#9
jtcfanof3 Busy at school Age: 33 Join Date: Aug 2005 Posts: 5,051 Location: barack hussein obama mmm mmm mmm User is: OffLine	Re: swapped my rear driveshaft to a single piece Golana,I think if you swaped too a 1 peice shaft,you may lose out on how low you can go when you bag it,the center bearing acts like as if thats where the tail shaft would be,this allows a more centered fulcrum when laying out in the back,if you have a 1 piece shaft most likelly your gonna hit the bottom of the cab before you get layed out.
	[Reply w/Quote]

11-25-2008, 10:35 PM	#10
88chevys10 Dropped Dime Join Date: Mar 2006 Posts: 136 Location: St. Peters User is: OffLine	Re: swapped my rear driveshaft to a single piece I did this exact same thing last year. I used a chop saw instead, but as well no vibrations. Took off a couple inches because of my v8 swap. I have a long bed. We had to move the carrier bearing back and shorten the back driveshaft. Spent about 8 hours doing it, but made real sure. One thing. Make sure you use a dial indicator. And before making the final weld on the driveshaft but it in there and run that to make it as true as possible. It it needs some adjusting smack it at the yoke with a hammer and try again. Once as true as you can get it. Make the final weld.
	[Reply w/Quote]

01-19-2009, 01:54 PM	#11
cheseburger Registered User Join Date: Jan 2009 Posts: 16 Location: User is: OffLine	Re: swapped my rear driveshaft to a single piece The biggest reason trucks go to a 2 piece drive shaft. Longer than 55inches the shaft will cease to rotate true and will start to ocilate out of round. Usually at high speed or at 70mph or higher. It wears out berrings and if it were to come apart front piece can wedge into asphalt flipping truck. Rarely seen it , uaually at track with high torque appl.
	[Reply w/Quote]

01-23-2009, 10:37 PM	#12
chucke2009 Registered User Age: 16 Join Date: Jan 2009 Posts: 27 Location: User is: OffLine	Re: swapped my rear driveshaft to a single piece real neat prank-i know its random, but stick a zip tie around someones driveshaft. Once they get going it starts to hit the car body and it sounds like the thing is fallling apart. Breaks off after about a mile or so :-)
	[Reply w/Quote]

02-21-2009, 03:21 AM	#13
jarrodh Registered User Age: 20 Join Date: Aug 2006 Posts: 779 Location: User is: OffLine	Re: swapped my rear driveshaft to a single piece Quote: Originally Posted by cheseburger The biggest reason trucks go to a 2 piece drive shaft. Longer than 55inches the shaft will cease to rotate true and will start to ocilate out of round. Usually at high speed or at 70mph or higher. It wears out berrings and if it were to come apart front piece can wedge into asphalt flipping truck. Rarely seen it , uaually at track with high torque appl. wasnt on a truck, but saw it happen on a friends 66? comet a year or 2 ago on the 1/4 mile.. it either the driveshaft boke, and did just that, or it was a leaf or traction bar broke, and pole vaulted his car, and it hapeened right the finish.. nearly killed him.. and yes ive herd that a long drive shaft can start to "whip" and shatter..all kinds of fun at speed..
	[Reply w/Quote]

02-25-2009, 02:16 PM	#14
SH-60B Registered Neanderthal Join Date: Nov 2007 Posts: 2,335 Location: Meriden/CT/USA User is: OffLine	Re: swapped my rear driveshaft to a single piece Quote: Originally Posted by cheseburger The biggest reason trucks go to a 2 piece drive shaft. Longer than 55inches the shaft will cease to rotate true and will start to ocilate out of round. Usually at high speed or at 70mph or higher. It wears out berrings and if it were to come apart front piece can wedge into asphalt flipping truck. Rarely seen it , uaually at track with high torque appl. The driveshaft didn't "ocilate out of round" in the van he got it out of, why would it in his pickup? MPH has little to do with driveshaft RPM, the rear end gear will dictate shaft rpm at a given speed. The shaft is spinning a lot faster with a 4.11 gear than a 2.73 gear.
	[Reply w/Quote]

03-17-2009, 02:37 PM	#15
david gmc Registered User Age: 34 Join Date: Mar 2009 Posts: 358 Location: User is: OffLine	Re: swapped my rear driveshaft to a single piece will a driveshaft outta an astro wrk in an s15???
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03-21-2009, 05:33 PM	#16
fastr68 easterwabbit Join Date: Sep 2002 Posts: 597 Location: Lincoln, IL User is: OffLine	Re: swapped my rear driveshaft to a single piece Quote: Originally Posted by david gmc will a driveshaft outta an astro wrk in an s15??? hi there hmm, well as far as what ? length? probably not. get the tape measure out but if its a hair longer then it can be cut down and used for sure ---------- 74" from tail end of the tranny back to the pinion yoke is the longest ive seen in stock form for a one piece shaft and that is under the 73-up 2wd full size trucks very common ------- its been many monts now since i cut and put mine in from the van and its doing perfect, truck is still smooth as silk going down the road all the vibrations and such have been totally gone, not even any hint of vibration in the steering wheel anymore either since i did this i drive this truck every day and alot and i couldnt ask for a better running driving truck especially at 196k miles now. heres a couple pics i took a minute ago, i see that my shaft has rubbed the carrier bearing crossmember a few times ahaha i need to do something about that apparently lol im shortening the driveshaft under the 78 c-10 pickup i recently acquired so i can go from the toasted original th350 to a 3L80HD from an 87 pickup in which is 3" longer than the th350 ive already cut it and cleaned it up, ready to weld the yoke on real soon i may take pics, if i remember to grab the camera, like i meant to when i did the van shaft. Last edited by fastr68 : 03-21-2009 at 05:36 PM.
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05-23-2009, 02:53 PM	#17
88GMCs-15 Registered User Age: 21 Join Date: Jun 2004 Posts: 796 Location: User is: OffLine	Re: swapped my rear driveshaft to a single piece Quote: Originally Posted by fastr68 ppl are too scared of things like this its no big deal as long as you are carefule not to change anthing other than the length then its fine in my case all i did was remove a measly 1.5" from the length very simple luck is nothing do with it as long as you weld the yoke back on lined up with the yoke on the other end of the shaft then youre fine mines doing perfect, smooth like new, awesome =) what happened to my two piece driveline was that the u joints froze and it caused the shaft to bind up and it became out of round or twisted and un repairable had a really bad shimmy shake in it around 30mph and when i loaded weight on the rear the entire truck would violently severely jump hop and i couldnt go over 10mph or i couldnt hold the steering wheel any longer like a brand new truck now anything else lemme know my front yoke coming out of the ass end of the tranny siezed up and course the front driveshaft was still turned so it tore up the u-joint in my ford ranger.. i was dropped the front end into a little mud hole and was trying to pull out of it and snap... and of course got stuck in 2wd so i had to get a couple quads to pull me out.
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06-30-2009, 12:02 AM	#18
the_s15_virgin Registered User Age: 34 Join Date: May 2009 Posts: 39 Location: Raytown Mo. User is: OffLine	Re: swapped my rear driveshaft to a single piece Can anyone give me an idea on a drive shaft to fit my 86 gmc s15 with a 82 2.8 v6 and 4 speed manual transmission swap? Anyone done this?
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07-07-2009, 01:11 AM	#19
Patriotslist Registered User Age: 38 Join Date: May 2009 Posts: 31 Location: User is: OffLine	Re: swapped my rear driveshaft to a single piece Drove a tow truck for 18 years. This made me think of a tow I once did. Did a call once where a guy did something similar with an old truck he did this with for some reason to lose the carrier bearing cuz it kept chewing them up and vibrating. The cross member where the carrier used to mount was in the way for the solid shaft "he made" so he torched it out. He was driving the truck down the hwy towards laughlin near the river run time of year and the front of the shaft broke where he welded it. Shaft went under the trucks back tire and it rolled into the dry lake bed. I only saw it afterwards of course but I envisioned a "catapult" scenario, hehe. His shit was scattered for about 500 feet, swept the highway for about an hour. He didn't get hurt luckily. I'm sure this ones fine, not trying to make you paranoid. Thought you might find it interesting or at least get a chuckle out of it.
	[Reply w/Quote]

10-16-2009, 03:33 PM	#20
fastr68 easterwabbit Join Date: Sep 2002 Posts: 597 Location: Lincoln, IL User is: OffLine	Re: swapped my rear driveshaft to a single piece even after all this time having swapped to a one piece shaft, i am curious as to why all these 118" WB trucks have a two piece driveline. the longest factory made one piece GM driveline i know of is under the full size trucks 73-up and they are 74" from the tail of the trans back to the pinion yoke. with the th350 9" tail and the 700r4 trans the 118" WB s-series tail to yoke distance is less than the full size trucks i know, so i just wonder... hmm..
	[Reply w/Quote]

10-16-2009, 03:36 PM	#21
fastr68 easterwabbit Join Date: Sep 2002 Posts: 597 Location: Lincoln, IL User is: OffLine	Re: swapped my rear driveshaft to a single piece Quote: Originally Posted by the_s15_virgin Can anyone give me an idea on a drive shaft to fit my 86 gmc s15 with a 82 2.8 v6 and 4 speed manual transmission swap? Anyone done this? tape measure and junk yard hunting look for one the same distance from trans tail back to the pinion yoke or one just about an inch more than this and have it cut yours could be 108" or 118" WB or ext cab WB even each has its own dshaft length the full size van one happens to be a hair longer than the 118" WB s-series and works out good
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