Does the rear end yoke interchange 84 to 86?

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jer
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Does the rear end yoke interchange 84 to 86?

Post by jer »

My 84 mpg+ pup rusted beyond saving. Once I removed the bed and axle the frame with a gentle pull was in two pieces. Found a nice 86 spacecab roller to put the drive train in. My problem is the 84 axle was set up with the smaller universal joint and attachment flange and the driveshaft is for the larger joint and flange. So my question is are the yokes interchangeable??? Can I simply replace the yoke from the older axle with the one from the newer axle and replace the input shaft seal while I'm at it too? This would allow use of factory driveshaft without modification....
Thanks in advance...

Jer
`82 LUV 4x4 c223t 5speed, a/c, ps, pb, 3" lift

`84 P’up c223 wvo conversion needing frame transplant
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puttputtinpup
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Re: Does the rear end yoke interchange 84 to 86?

Post by puttputtinpup »

If those don't interchange, you might consider using the gasser transmission & driveshaft from the 86 and leave it intact.

You'd have to do what we call the diesel 5speed tranny upgrade swapping the front half of your diesel transmission over to the gasser tranny (or maybe won't work if yours is a mpg 4speed?)....shelf that idea for now.

If the rearend yoke flanges won't swap, a driveshaft shop can change out the rear portion of the driveshafts, rebalance it, and good to go.
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JoeIsuzu
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Re: Does the rear end yoke interchange 84 to 86?

Post by JoeIsuzu »

You ran into the same issue I did. The '86 rear flange uses a larger U-joint, and so far, nobody has come up with a "hybrid" joint that will mate the old shaft to the newer yoke.

I agree with Andy, use the '86 transmission if you have it. You'll need that 5th gear anyway. If the '86 was gas, it has a 4.10 rear axle.

Jack
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Re: Does the rear end yoke interchange 84 to 86?

Post by puttputtinpup »

JoeIsuzu wrote:You ran into the same issue I did. The '86 rear flange uses a larger U-joint, and so far, nobody has come up with a "hybrid" joint that will mate the old shaft to the newer yoke.

I agree with Andy, use the '86 transmission if you have it. You'll need that 5th gear anyway. If the '86 was gas, it has a 4.10 rear axle.

Jack

Good catch. His truck wouldn't be much of an MPG with a 4.10 rear diff. His has a 3.42. If be swaps bellhousing (if the 4 speed he has will swap), his speedometer at least will still be correct. Jerry said once if a 4 speed front input shaft & countershaft cover has the same number of bolts holding it on, the 4 speed front case should swap with the front case from the 5speed.
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jer
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Re: Does the rear end yoke interchange 84 to 86?

Post by jer »

A little more info: the transmission combination is not at issue as the 2 section driveshaft only has the large u-joint at the axle. The u-joints at the transmission and the carrier assembly are the smaller joints. I have a 5 speed installed and fitting perfectly to the mounts and the driveshaft. The 84 has a 1 piece shaft. The only point of contention is the axle to the driveshaft. Unless I'm mistaken the only reasonable options I see before me is the yoke from the 86 axle fits the 84 axle or I cut the driveshaft and weld on an appropriate mount.... thanks again for all the feedback.... jer
`82 LUV 4x4 c223t 5speed, a/c, ps, pb, 3" lift

`84 P’up c223 wvo conversion needing frame transplant
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jer
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Re: Does the rear end yoke interchange 84 to 86?

Post by jer »

Also ... if I know in advance whether or not the yokes will interchange it could eliminate the potential misadjustment of the rear end.
`82 LUV 4x4 c223t 5speed, a/c, ps, pb, 3" lift

`84 P’up c223 wvo conversion needing frame transplant
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puttputtinpup
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Re: Does the rear end yoke interchange 84 to 86?

Post by puttputtinpup »

Is your installed 5 speed from a diesel engine or from a gas engine? Bolt pattern is different gas & diesel.

I wish i could answer your question about the yoke at the pinion bear.
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jer
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Re: Does the rear end yoke interchange 84 to 86?

Post by jer »

puttputtinpup wrote:Is your installed 5 speed from a diesel engine or from a gas engine? Bolt pattern is different gas & diesel.

I wish i could answer your question about the yoke at the pinion bear.


Yes is a diesel trans ...if it was gas then starter bump would be on other side and would not mount to engine ....
`82 LUV 4x4 c223t 5speed, a/c, ps, pb, 3" lift

`84 P’up c223 wvo conversion needing frame transplant
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jer
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Re: Does the rear end yoke interchange 84 to 86?

Post by jer »

Picture is worth a 1000 words
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`82 LUV 4x4 c223t 5speed, a/c, ps, pb, 3" lift

`84 P’up c223 wvo conversion needing frame transplant
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puttputtinpup
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Re: Does the rear end yoke interchange 84 to 86?

Post by puttputtinpup »

I'd check with jerry Lemond about the pinion yoke swappability if someone else like Paul or Mark doesn't chime in in the next little bit.
Jerry will know the answer. His email is
Jlemond@bellsouth.net
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jer
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Re: Does the rear end yoke interchange 84 to 86?

Post by jer »

Figured I'd let everyone who was interested know... I pulled the yokes and they appear to be completely interchangeable. I did not get out a mike but by the eyeball and ruler it is all the same on the back side. Fits nicely....
`82 LUV 4x4 c223t 5speed, a/c, ps, pb, 3" lift

`84 P’up c223 wvo conversion needing frame transplant
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puttputtinpup
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Re: Does the rear end yoke interchange 84 to 86?

Post by puttputtinpup »

jer wrote:Figured I'd let everyone who was interested know... I pulled the yokes and they appear to be completely interchangeable. I did not get out a mike but by the eyeball and ruler it is all the same on the back side. Fits nicely....

Be careful when tightening the lrg nut holding the yoke on not to over tighten it beyond what it may have been taking it off. My son had the pinion seal replaced once by the Chevy dealer on his 82LUV and I had a seal chg on an 84 I had, well the previous owner insisted on having it changed before selling it to me. A garage did it.(getting sidetracked here) That yoke actually was loose and caused the leak. And....it was an out of balanced driveshaft that caused the yoke to come loose
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jer
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Re: Does the rear end yoke interchange 84 to 86?

Post by jer »

Thanks puttputtinpup... I counted turns of the nut when removing and am careful to tighten enough to remove play but not effect crush sleeve...
`82 LUV 4x4 c223t 5speed, a/c, ps, pb, 3" lift

`84 P’up c223 wvo conversion needing frame transplant
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