1978 F-250 Front Driveshaft

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May 7, 2015 | 09:00 PM

55 M-100

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From: Redvers, SK

1978 F-250 Front Driveshaft

I put a 6 inch Skyjacker suspension lift on my 78 F-250. I had the front drive shaft extended and the cv head changed. I have used the 4X4 very little and the cv head is toast already. I`m guessing the angle of the drive shaft is too much now with the lift. Any input would be much appreciated.

May 8, 2015 | 06:27 AM

bigdan1979f-250

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From: mid-MO

That seems a little out of the ordinary. Couple of questions, why did you change the cv? Was the old one wore out? What angle does the driveshaft sit at currently? And how many miles are on it since you put it in? Specifically, what is broke or wore out? U-joints?

May 8, 2015 | 03:37 PM

55 M-100

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From: Redvers, SK

The old cv head was worn out. I think it had a lot of hard miles on it. I can't remember exactly what the angle is on it but I think it was 18 degrees coming off the dif and 22 degrees off of the t-case. I would guess it has a total 150 miles on it at the most. You'll have to forgive my lack of proper terminology but the retaining ring that holds the ball in place for the cv head looks like it let go. I'd take a picture but the drive shaft is at the machine shop right now. The u joints are new and appear to be unharmed. Maybe it was just a faulty head? I just don't wanna spend the money on a new head if it's going to happen again. This the first lift I've ever put on a truck so these types of issues are all new to me. Thanks for your help.

May 8, 2015 | 04:52 PM

bigdan1979f-250

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My 79 has a cv on the front, just like yours. Granted, I don't have the 6" lift, just an add a leaf that the PO added. It used to not have the CV style shaft in it and never bound up on me or broke, worked fine. So, I would say a 6" lift with the front CV shaft would work fine. You might be right, maybe it was just a junk CV component. You going to have it replaced and try it again? I am curious if the same thing will happen or if it will work ok.

May 8, 2015 | 09:22 PM

55 M-100

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From: Redvers, SK

I'm not 100% sure what to do with it. I'm hoping it was a faulty part but I'm gonna do some research to see if there are other options. At the machine shop he had a drive shaft off of a 05 dodge 2500 and it has a lot beefier cv setup. Maybe something like that would be better. Was your old front drive shaft a u joint on each end with a slip yoke?

May 9, 2015 | 04:38 AM

tjc transport

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all three of mine were slip yoke and 2 joints, no CV unit.
i never had any problems with any of them, but they are all stock height too.

May 9, 2015 | 10:28 AM

bigdan1979f-250

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Yes, my old one was u joint with slip yoke. If you go with a larger setup like a modified dodge shaft like you were talking about, you would more than likely have to change out the yoke on your transfer case depending on what size u joints it uses. Or you could possibly find a u joint that has say a 1330 on one cross and 1350 size on the other cross. I do have spicer part numbers for this scenario, swiped from Alpha Omega who I don't think is on here anymore. I'm no expert, but do think the cv style helps keep u joints alive, especially with your 6" lift. If it were me, I wouldn't run a driveshaft without one on a lifted setup.