2 Piecs DS alignment No Guibo)

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JimG
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2 Piecs DS alignment No Guibo)

Post by JimG » Wed Jun 13, 2018 6:06 pm

Those of you that have a two piece driveshaft with u-joints ( no guibo) how did you align it?
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86 XR4TI, 165K, IC, RR, PBR Fronts, T-bird Rear Discs
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merkurdriver
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Re: 2 Piecs DS alignment No Guibo)

Post by merkurdriver » Thu Jun 14, 2018 1:22 am

inclinometer maybe?

john keefe
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Re: 2 Piecs DS alignment No Guibo)

Post by john keefe » Thu Jun 14, 2018 2:59 am

If you have a thin, pencil laser, tape it to the rear portion, facing forward; make sure its even on the DS, not tweaked to one side or the other. Then note how it aligns, or misaligns with the u-joint as you rotate the DS. You might have to cut out a cardboard, or beer carton into a sheet you can slip over the DS near the cradle to give you reference. Rotate the rear prop, see where the laser spread is, then move the cradle right an left even on both sides. Do the same with shimming up or down for vertical alignment.

If your rear u-joint is worn, though, it will have developed a pattern as it sits at a pinion angle to the Diff. Probably only in the vertical. Unlikely it was offset R or L, unless it was removed and reinstalled improperly a long time ago? If its not a "new" setup, I'd try shimming, or removing shims from the cradle to see if you can tell a difference in how smoothly it rotates. Where its smooth, that's your original angle, or close to it. It's more than likely the angle produced by the stock cradle shims. Hope you have those.

If you can't tell, then you're just going to have to align it R or L with the laser, spray paint or lay a stripe where the cradle sits on the frame for R/L reference. Assuming you get the Up and Down equal, then you're going to have to test drive it, and add, or subtract shim thickness between the cradle and frame. At least with the junction line painted at the cradle-frame edge, you'll keep your R & L balance.

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Esteban
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Re: 2 Piecs DS alignment No Guibo)

Post by Esteban » Thu Jun 21, 2018 7:55 pm

Even with a 2pc DS, I found it best to make sure the pinion angles of the trans and diff are parallel or within half a degree (use shims under the trans mount or under the motor mounts to change this angle). Then I install the driveshaft and use shims to move the CSB (center support bearing) down until both halves of the DS have the same angle. The CSB will have SOME lateral play 2-3mm worth, I just eyeball it to center. No vibes at all. Not sure you need the dial indicator method here. The CSB allows the DS to move a good amount so being exact with the dial wont do much if the DS is not balanced to begin with.

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