Can I drive truck up to 70mph safely with just the front driveshaft installed?

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HotRodPC

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Have you driven it yet with front driveshaft only?
 

chengny

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This isn't a lifted truck is it - still stock suspension right? So angularity of the drive line wouldn't be an issue.

I think indexing/phasing have been discussed and ruled out right? But I was wondering what he means by this (from the initial post):

"Got the conversation joint on the rear of the shaft as well. "

Is the drive shaft the same one as with the 10-bolt or did the new axle come with it's native drive shaft?


How about the way the axle tube is secured to the spring stacks. Proper sized u-bolts, perches and anchor plates etc?

Just some food for thought and that's it for me on this one. I'm in over my head - I usually don't even go this far down on the thread list.

I generally stay up near the top and hit the hanging curveballs like "Why doesn't my horn beep?"
 

DoubleDingo

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I have only been able skim through this. Is the rear driveshaft two piece because of the conversion piece you put on it? If so, was everything put back in time or tune with each other when the u-joints were replaced. If not then the driveshaft will not be balanced anymore. I know with two piece driveshafts you have to mark the relation of the two halves before taking them apart so they stay balanced when put back together with the lines lined up. Just a thought.
 

HotRodPC

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Being Fo Buh Fo, I'd imagine it's a single piece rear dshaft.
 

Mattchu60

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Well folks....I dont want to jinx it, but I think I got it.


Took the shaft out again tonight, got a new precision u-joint for the front (which was just replaced, fyi) and marked the location of the slip joint on the shaft.

Took it apart, installed new u-joint, and flipped the slip joint 180. Took for a short 4 mile drive and it feels much smoother. I did this because I called a driveline shop and they said even the slip joint can affect balance if its flipped 180 (never marked it when I installed new joint, took a chance that I installed it backwards, and I think I did).

Its noticeably better, I think I got it. Pretty simple/stupid mistake.

I wont drive it to work for a few days, but when I do I am hoping its solved.
 

HotRodPC

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Unn Huhh !!! That's why somebody up there several comments back mentioned for ****'s n giggles flip the 180 degrees., cuz hell yes it does make a difference. Now it wasn't the front shaft I was talking about, or the 2 pieces but for certain, 180 out will do it. Lesson learned, ALWAYS, ALWAYS ALWAYS marks your shaft orientation. ESPECIALLY 2 pieces and/or Slip yoke units.

On my 2 piece shafts when I take them apart, I use my stamp set and the letter V as an arrow on both pieces to look like > < on my 2 pieces. When I pull a trans, I use a screwdriver and scratch the yoke and it's position on the driveshaft so I know it's going back in EXACTLY like I pulled it out.

Glad you got it. I don't think you need to worry about jinxing it. Certainly makes perfect sense. Now lets hope from driving it this way that you have damaged any pinion bearings or bearing races, cardon joints etc. :waytogo:
 

chengny

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I spray paint (yellow) along one side.
 

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Being Fo Buh Fo, I'd imagine it's a single piece rear dshaft.

That's what I thought but thought I would toss that out there.
 

DoubleDingo

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Glad you got it smoothed out, hope it is fixed and like others said, that no damage was done.
 

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I doubt any damage was done, wasnt driven too much and the vibration was slight, its just that I didnt expect any vibration at all. When I had the shaft out I look into the TC and spun the shaft, the bearings feel tight and spun smooth.

Hoping its fixed, like i said, only drove 4 miles but I could tell it was better even at lower speeds.
 

MrMarty51

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I use My chisel and make a long line, about an inch to a inch and a half, then use the chisel to make the v on the end pointing to duh other half, mark the other the same.
Then, it does`nt matter who takes it apart again, there`d be no question as to the orientation.
 

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