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Discussion Starter · #1 ·
I was finally able to install the production versions of the 3/4 ton to 1/2 ton cv adapters last weekend. I had recieved them from Jacqson about a month ago but I hadn't gotten aroung to installing them. It worked out great in fact it went a little better than expected. I needed to pick up a different brand 3/4 cv from Advanced Auto parts being as they didn't have anymore of the other ones in stock. I know Advance has a bad wrap but it was the only place around that had them in stock. The new one fit better anyway. The old version that I had needed to have the lower boot moved down about an inch or so so it would clear my sway bar link. The new version that I had cleared just fine without modifiying because it had the boot mounted farther down the shaft. Down the road I will probably switch out the older shaft for the new better version.

I know its no D60. But its better than the puny 1/2 ton shafts but not as strong as the cv's offered by Rough Country. While those I would be concerned with blowing the front diff, these I'm not too worried. With all the mall cruising and the occasional mud run I really don't need a sas. Now I need all the front upgrades from Cognito and I should be pretty well set.

Part# 4990013 for the cv shaft that worked the best
Part# 15870257 for the cv shaft that needed to move the boot.

*Never mind the rust. Minnesota in the winter sucks*

Driverside with the modified lower boot
DSC00188.jpg


Passenger side with the unmodiifed cv shaft
DSC00189.jpg


Passenger side cv to diff mount with the new adapter.
DSC00190.jpg
 

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328 Posts
Discussion Starter · #4 ·
About $350 and some change. Thats with the adapters, fasteners, and cv's with a lifetime warrenty. Not too bad since most that wheel eventually blow or more cv's anyway and while your replacing the cv(s) you might as well upgrade too. I forgot to mention that these cv's do help with the angle as well. Its hard to tell in these pics since mine are nearly flat but they give you another couple of degrees before they bind. In fact I had the control arm resting on the bumpstop and they were no where near binding. And just to make sure I pulled the upper boot down to see if the tripod joint pulled out of the housing. I was still in the housing about a half inch or so. Even if its only a few degrees every little bit helps when your running a knuckle kit cranked up.
 

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Suburbanite
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597 Posts
i thought the output shaft was different diameter on the 3/4 ton
That's the reason for the adapter. It allows you to mount the 3/4 ton CV to the 1/2 ton Diff Flange. On NBS 1500 trucks the 3/4 ton CV's are a direct bolt in to the wheel hub flange.
 

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boogity boogity
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995 Posts
im really interested in getting those adapters, could someone pm me with a price?
 

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Left Jizz
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1,225 Posts
I also Want those adapters if you know where you can find them please pm me.
Thanks

PM this guy: Jacqson

There are also several threads on the development, use the search button.
 

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Fluffy and Armed
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636 Posts
+1 I've talked to him, and he really knows his stuff! Now I just need to get some $$$ together and place an order.
 

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Discussion Starter · #13 ·
We were looking at setting something up for the OBS but there are too many issues that wouldn't really make it cost effective. The shafts are different length from side to side. Plus the issue with abs gear on the 3/4 ton shaft and the fact that the 3/4 cv's would need to be machined down 2 mm on the wheel hub side in order to fit in the 1/2 ton hub.
 

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Suburbanite
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597 Posts
We were looking at setting something up for the OBS but there are too many issues that wouldn't really make it cost effective. The shafts are different length from side to side. Plus the issue with abs gear on the 3/4 ton shaft and the fact that the 3/4 cv's would need to be machined down 2 mm on the wheel hub side in order to fit in the 1/2 ton hub.
The adapter will still work but if someone is interested, send me the installed length of your 1/2 ton CV and I will compare measurements with the 3/4 ton CV. It will work, there will just be an extra cost to machine the Hub end of the 3/4 ton CV.
 

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Typical Smart-Ass
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1,147 Posts
BTW, congrats on getting that finished.


thArf, I believe the output shaft is different on obs from 1/2 ton to 3/4 ton, unless I am just thinking of a 1 ton that is different.. I do know that the nbs and obs output shaft for the 1/2 tons is identical as is bolt pattern.
 

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Suburbanite
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597 Posts
BTW, congrats on getting that finished.

Thanks, I appreciate that, and for answering my previous questions and concerns. A couple of other quick questions as I'm still trying to figure out this OBS thing. If your 1/2 ton OBS has ABS does the hub end of the shaft have that gear on the CV? Would the 3/4 ton CV with the same gear fit into the 1/2 ton hub if you mill down the hub end to 78mm?
 

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submarine z71
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1,312 Posts
awsome, now wheel it to hell and back and see how they hold up :LOL:
 

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Typical Smart-Ass
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1,147 Posts
Thanks, I appreciate that, and for answering my previous questions and concerns. A couple of other quick questions as I'm still trying to figure out this OBS thing. If your 1/2 ton OBS has ABS does the hub end of the shaft have that gear on the CV? Would the 3/4 ton CV with the same gear fit into the 1/2 ton hub if you mill down the hub end to 78mm?
The ABS ring easily goes on and off any CV joint. Mine doesn't have the ABS ring on the CV as it is built into the hub assembly. Some obs CV's do have the abs ring, but as I said they go on and off.

If the NBS 3/4 ton fits into the NBS 1/2 ton, it should fit into the OBS 1/2 ton.
 

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Suburbanite
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597 Posts
The ABS ring easily goes on and off any CV joint. Mine doesn't have the ABS ring on the CV as it is built into the hub assembly. Some obs CV's do have the abs ring, but as I said they go on and off.

If the NBS 3/4 ton fits into the NBS 1/2 ton, it should fit into the OBS 1/2 ton.
Gotcha, However if you remove that ring won't it screw up the ABS, if the truck is so equipped? My concern is that if you change out your 1/2 ton CV's for the 3/4 ton units and your 1/2 ton CV's have that ring for your ABS will the 3/4 ton CV with the same gear on it for your ABS fit into the 1/2 ton hub and work properly if you machine the 3/4 ton hub end down to 78mm. I figure the swap will work fine on the OBS trucks like yours that don't have that gear because all you have to do is use the adapter with a 3/4 ton CV that has the hub end machined down to 78mm. If your 1/2 ton CV has that gear, will a 3/4 ton CV with that gear and the hub end machined to 78mm work the same way as the 1/2 ton CV.
EDIT: I guess what I'm trying to say is: Is the ABS gear on the 1/2 ton CV the same size in diameter as the one on the 3/4 ton CV, because if it is the fit and function should be no problem if you did the swap.
 
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