Anybody shorten a driveline?

[jwn1975]

I am in the process of shortning my frame from LWB to SWB. I want to run a straight driveline with no slip yoke. Can I buy a piece of round tubing the correct diameter and thickness and center up the ends I cut off my long drive shaft and weld them on? Any suggestions, balancing, which way to allign the u-joints? I know having one made would be the way to go but im on a budget.

[Frizzle Fry]

This is one place you don't want to skimp on. Either find one the right length at a yard (good luck) or get one that's slightly too long and have is shortened and balanced by a shop.

[ChevLoRay]

I'm sure it's been done many, many times. Balancing is key to the life of anything in the driveline...u-joints, transmission and rear end, to be sure. The yokes of the driveshaft have to be "phased" properly. Look at the driveshaft you take out and see how the yokes are positioned. The driveshaft you build should be done the same way. After you get it all together, I'd take it to a machine shop, maybe a NAPA shop, and have it spun to check it for balance. If that is the only thing you have done by someone else, assuming you have the talent you need to cut and weld, you'll still save $$. As an aside, here in Central Arkansas, it runs about $75 to have done what you want done, at a business that is in business to do just that.

[19673ontree]

I have done this MANY times without any problem ,
it is hard to describe without a picture but I will try

#1 the key to the success is getting the end's plumb (STRAIGHT) (SQAURE)

#2 get a long piece of something straight and clamp it to the end's once you get the length right TEST FIT then TEST FIT IT AGAIN then TEST FIT IT !!!

you will want to use the straight edge ? piece of angle iron ? 2x4 ? just something straight to hold the end's in a nice even form while welding ,
give me a minute and I will make a drawing ,,,,,,,,,,,,,,,,,,,,,,,

[19673ontree]

here is a drawing of how to do it , if you do it like this it will not shake , I have done many like this without a problem ,
and just to be saying if you were doing this for a 200 mph race car yes you would need to have it balanced ! for a 1967 to 1972 chevy pickup NO!

[crazy longhorn]

I have cut & welded a couple shafts......but i dont reccomend you do it on a shaft That long crazyL

[jwn1975]

Thanks guys, Ill give "er" a shot and take it to be balanced. I can run a welder and a sawzall. If it wont balance, Ill have them build one.

[fullerbuilt]

your rear diff. moves forward and backwards as you roll down the road. you need a slip yoke. or your brgs. will go by,by, and you will hammer your running gear.

[jwn1975]

I have a 67 camaro that doesnt have a slip yoke and everything is OK. I dont plan on hauling anything with the truck nor pulling any trailers. Still have to have a slip yoke?

[fullerbuilt]

yep. even with very small movement going on, it is still happening. your parts wont last very long, and your running gear will not be happy.

[67_C-30]

Originally Posted by jwn1975

I have a 67 camaro that doesnt have a slip yoke and everything is OK. I dont plan on hauling anything with the truck nor pulling any trailers. Still have to have a slip yoke?

You mean it doesn't have a 2 piece shaft with center slip yoke, but it does have the normal slip yoke going into the tranny right? As long as you have the slip yoke going into tranny you don't need the center yoke on a SWB.

[jwn1975]

Gotcha,
Thanks guys

[Longhorn Man]

i would still never build a shaft.
The junk yard has about eleventy billion driveshafts just laying around.

[brad_man_72]

i shorten drivelines everyday, its what i do. believe me save the time effort and money by having a shop that specializes in drivelines build your driveshaft or shorten one that is longer (cheapest route). buy the good u-joints check your pinion angle, and you should have no problems.
even using a lathe, our setups, and making our shafts with about 50% of oem tolerances the shafts can still take quite a bit of weight when in the ballancer.
welding your driveshaft is fine to get your truck out of the field, but not to take down the highway.