Author Topic: Changing 4x4 to 2wd  (Read 8036 times)

Offline BillB

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Changing 4x4 to 2wd
« on: April 19, 2013, 09:49:49 am »
Hey guys, I have a 81 swb 4x4 frame with suspension, the transfer case is thrashed, front diff is shot etc....to make a long story short, I have access to a  2wd 81 3/4  lwb, want to know if the front suspension from the 3/4, 2wd will adapt to the 4x4 frame converting from a 4x4 to 2wd?  Thanks in advance, finding out here whether this can be done will sure save time and frustration if it cant be done :)

Offline pholliday1

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Re: Changing 4x4 to 2wd
« Reply #1 on: April 19, 2013, 03:00:54 pm »
O....Anything can be done the general school of thought is that is requires a lot of fab work. So if you have those items available then have at it.However its not considered an "easy" project what so ever
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Offline BillB

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Re: Changing 4x4 to 2wd
« Reply #2 on: April 19, 2013, 08:01:20 pm »
Thanks for the info, was hoping for a bolt on conversion, maybe time to go back to the thinking board. :-\

Offline Tx_Phil

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Changing 4x4 to 2wd
« Reply #3 on: April 19, 2013, 08:40:51 pm »
I'm going to show my ignorance here but could you just pull the gut out of the front diff and drop the drive shaft and run it as a 2wd?

Have you looked into salvage yard parts or pick-part stuff?  I'm guessing you could repair the diff and transfer case cheaper than converting to a stock 2wd suspension when you factor in time and frustration and such.

Offline zieg85

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Re: Changing 4x4 to 2wd
« Reply #4 on: April 19, 2013, 09:02:05 pm »
A donor frame, nice sharp air chisel and grade 8 bolts.  I can't imagine it would be that hard to do.  Very time consuming though.  Captkaos has a build thread on here doing that same thing on a Blazer.
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Offline Irish_Alley

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Re: Changing 4x4 to 2wd
« Reply #5 on: April 20, 2013, 07:03:57 am »
most if swapping will swap from a 4x2 to 4x4 not this way around. its been over 10 years since i looked at my 86 4x2 can barely remember anything about it. but if i had to i would do like phil said and gut everything and run her
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Offline BillB

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Re: Changing 4x4 to 2wd
« Reply #6 on: April 20, 2013, 09:15:29 am »
What I am trying to do is put together a 81 swb stepside 2wd, I have all I need except the swb frame is  4x4 running gear. I am hoping to remove the front axle, springs, etc and use the front  suspension from a donor 81 3/4 lwb 2wd. The 3/4 lwd frame is in another location so I cannot compare the 2 side by side, I am thinking  the frames are  identical so I will be able to make the switch. I will pick up the 3/4 frame next week so will compare then, was just hoping that this swap had been done before so I would have my ducks in a row before I start.   Thanks.

Offline Irish_Alley

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Re: Changing 4x4 to 2wd
« Reply #7 on: April 20, 2013, 09:55:59 am »
the frames are the same from what i compared 1/2 ton to 3/4 ton. might have to drill holes and so on but i think its all pretty simple. done a 4x2 to 4x4 and it was all pretty much cut and paste
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Offline Jason S

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Re: Changing 4x4 to 2wd
« Reply #8 on: April 20, 2013, 11:09:59 am »
Are you going to keep the 8-lug brake/wheel setup, essentially building a 3/4-ton shortbed stepside truck?
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Offline Irish_Alley

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Re: Changing 4x4 to 2wd
« Reply #9 on: April 20, 2013, 12:18:27 pm »
lol the little details; not a with 1/2 ton front he would also have to swap rears or the axle shafts if possible
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Offline BillB

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Re: Changing 4x4 to 2wd
« Reply #10 on: April 20, 2013, 04:28:31 pm »
Now to show just how quickly things can change in my square body world, if I were to replace the 4x4 front axel setup, hub to hub do I need to match gear ratios (front to rear)?  Sorry to show my ignorance here but As you can see I know very little when it comes to 4x4s. (Just an example of how little I do know) lol.   :D

Offline zieg85

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Re: Changing 4x4 to 2wd
« Reply #11 on: April 20, 2013, 04:35:13 pm »
The gear ratios need to match if you are going to use the 4 wheel drive.
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Offline BillB

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Re: Changing 4x4 to 2wd
« Reply #12 on: April 20, 2013, 05:03:52 pm »
Thanks zieg85, now for another show of ignorance,is there identification marks on the axels to show the gear ratio? If so where are they located?

Offline zieg85

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Re: Changing 4x4 to 2wd
« Reply #13 on: April 20, 2013, 05:53:09 pm »
Only sure way to tell is take the diff cover off and look at the ring gear, rotate it around, you will see 2 numbers, for example 40/13 which is a 3.08.  If they are original to the truck and you have the sticker on the inside of the glove box door it will tell you or give you a RPO code like a HE3 for example.  Report your findings.

http://www.rpocodes.com/GM-RPO-codes/gmrpocodesGthroughM.html should help you know what you have or originally came in the truck
« Last Edit: April 20, 2013, 06:23:20 pm by zieg85 »
Carl 
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Offline Blazin

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Re: Changing 4x4 to 2wd
« Reply #14 on: April 24, 2013, 12:54:36 am »
If you plan to swap the 4x4 over to a 4x2 you also need to swap the rear spring shackles / hangers as well to 2 wheel drive pieces.
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