Driveshaft question

C Body Bob

Old Man with a Hat
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Ok on my D440 truck project I had a took my driveshaft to a local driveshaft shop. Told him it was too short & I needed 52 inches center to center. He wrote it on the driveshaft in that yellow marker. He called this morning & said it was ready. Picked it up & never gave it a moments though to measure it. Got home & decided to pull a tape & its 51 1/2 center to center. Called him up. He couldn't believe he had cut the tube too short. Told me to try it & if I won't happy he'd make it right. Also he said he balanced it yet I see no weights. There is a lot of welding slag on it & what looks to me to be sloppy welds. I think he got in a hurry. Anyway. Here's pics of the ends & a pic of it installed. Opinions please. Is this safe to run. It's a 440 pick up with 3.91 sure grip. Also it looks like I have 2 1/2 inches of spline engagement & another 1 1/2 of non splined engagement
 
I think the engagement will be fine, but those welds and "balancing" look suspect. Any balancing there should be small round weights welded on. near front and/or rear.
 
You want there to be some ability to slide in and out, right now you have about an inch it can go in before it will bottom out under heavy acceleration. It could probably do with a bit more being you have a 440 in the vehicle. Under heavy acceleration the rear axle is going to push forward a bit sliding the drive shift further into the transmission.
 
bbb , had a 340 4spd with to long a line in it , destroyed the rear bushing in the tail stock of the trans and the yoke too . did not do the output splines any good either , rear suspension don't work right as well . and yes the front of the rear springs will wrap up on the pick up and torque the line out a bit . i clamp off the front of the springs with two clamps and at least one on the rear section . made the p/u handle better as well and you can see the amount of spline hang out .

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You want there to be some ability to slide in and out, right now you have about an inch it can go in before it will bottom out under heavy acceleration. It could probably do with a bit more being you have a 440 in the vehicle. Under heavy acceleration the rear axle is going to push forward a bit sliding the drive shift further into the transmission.
I have an inch & a half.
 
View attachment 123049 View attachment 123050 View attachment 123051 Ok on my D440 truck project I had a took my driveshaft to a local driveshaft shop. Told him it was too short & I needed 52 inches center to center. He wrote it on the driveshaft in that yellow marker. He called this morning & said it was ready. Picked it up & never gave it a moments though to measure it. Got home & decided to pull a tape & its 51 1/2 center to center. Called him up. He couldn't believe he had cut the tube too short. Told me to try it & if I won't happy he'd make it right. Also he said he balanced it yet I see no weights. There is a lot of welding slag on it & what looks to me to be sloppy welds. I think he got in a hurry. Anyway. Here's pics of the ends & a pic of it installed. Opinions please. Is this safe to run. It's a 440 pick up with 3.91 sure grip. Also it looks like I have 2 1/2 inches of spline engagement & another 1 1/2 of non splined engagement

If the builder had any knowledge of shaft building, he not only would have confirmed the proper length but recommend replacing the OE universals with heavier Spicer's. Mopars original universal retaining system was not only hooky but the joints were specific to Mopar in size and very light duty compared to other car manufacturers.
440's are capable of quite a bit of torque so if you're gonna replace the shaft, upgrading a bit isn't gonna cost that much more.
 
Should be okay length wise. Yeah the small joints are a little weak but putting a groove in the ear of the yoke for the retaining clip, (GM) is not that good for strength either. 2 5/8 joints have lived behind Hemi cars for a lot of years. Besides pick up trucks have no traction anyway so I doubt the 2 1/8 joint will be bothered by it. Same for the weld if it is a stock tube it is way weakekr than that weld.
Either way stick it in and use it if it snaps you get to inspect the innereds of your trans.
 
man,i wouldnt even put that In my truck...
look at the welds!!
balanced? i dont think so.

also,post 13 mr yatzee nails it as well.
upgrade now and never have to worry about it.
thats the way to go.

btw for driveshafts i use an actual company.
keep in mind how fast that things turning under your truck....
 
It's a work in progress. I'll put a new front joint in. Already done the back one. I am a little worried about the welds. This is a drive shaft shop.
 
Yesterday I drove over to Jacksonville to pick up a new driveshaft for our 63 Sport Fury. We had a transmission rebuilt and beefed up. It was from a 65 dodge (I think) push-button with spline shaft instead of the factory trunnion joint. We needed a longer shaft, and had a new one made. It looked good, but when I crawled under to install it the driveshaft wasn't the length we ordered, just a new one the same as the old one. Do these welds look OK? Back to Jacksonville next week. It happens.

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I am a little worried about the welds. This is a drive shaft shop
The fact that they are a driveshaft shop and gave you a shaft with welds like that is concern but other than sloppy it looks okay you can't really v it in and have it lay perfectly flat because the tube is only .090 and divits next to the bead would reduce the thickness even more.
 
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