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Discussion Starter #1
Anyone ever shorten there rear diff themselves? What type of jigging would need to be made? This is a 94 olds bravada 7.5 rear end going into a 62HT. Major buget limitations here. so DIY a must.One more ? where would be a good place to get shortend axles on the cheap? looking a total of 3 inches shorter 1.5 a side.

Thanks Dave.
 

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I narrowed my 12 bolt myself. Most people told me I could not do it myself or should not do it myself. Normally you use a jig that is bassically a long straight threaded shaft with some ends on it that hold the axle housing ends straight while you weld. Unfortunatley, these jigs cost about $250 so its not too cost effective. I like to try an figure out ways to do things when I don't have all the specialized tools. Here is how I did mine:

I bought new housing ends from Moser Engineering. They are really nicely made. They take the larger ford bearings so they will work with Moser HD axels. The ends are pre-beveled for proper weld penatration. I started off by borowing a good precision machinist's level. These are similar to normal levels, but the bubble only indicates something like +/- 1/2 degree at the extreems. After carefully measuring where to cut the axel housing tubes, I cut them using a cut off saw (14" abrasive saw). After cleaning up the ends of the tubes I made sure the rear end was supported on a set up jack stands. I made sure the rear end was absolutly level. Rotated the housing several times and re-measured it for level. When I was sure it was straight and level. I tacked on the ends. Then I used the level vertically on the face of the ends themselves. As you rotate the entire housing, if the ends are not on straight, the level will vary as you rotate everything. I had to give them a few taps here and there with a hammer (they were just barely tack welded on at this point) Once I had them super straight, I welded them just a littel more and then re-checked everything. Once I was satisfied, I welded around the tubes about 1/4 of the way at a time. First one side, then the other, then the another 1/4 way around. etc. In the end, it turned out reaaly nice.
Ron
 

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Man that did turn out real nice. Do you have a p/n for the tube ends? And were did you get them? summit?
 

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Damn those are nice but 90 bucks a pair:eek:holy shat batman! did i mention the budget,I'm hopeing for $300 or under for full deal (perfer under)
 

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Anyone ever shorten there rear diff themselves? What type of jigging would need to be made? This is a 94 olds bravada 7.5 rear end going into a 62HT. Major buget limitations here. so DIY a must.One more ? where would be a good place to get shortend axles on the cheap? looking a total of 3 inches shorter 1.5 a side.

Thanks Dave.
If it's out of a 2 wheel drive Bravada it should already be about 3.5 inches shorter.
 

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Damn those are nice but 90 bucks a pair:eek:holy shat batman! did i mention the budget,I'm hopeing for $300 or under for full deal (perfer under)
hey dave look at the thread for 63 rearend swap might iterest ya I also have a verry nerrow 8 inch ford out of a maveric but it has real high gears, it was cobled under a 62 parts car I had , fit well and look more narrow than the stock nova, just an Idea , and I think you are close by if you want to talk or are interested in the 8 inch ford my cell # is 509-671-1582 ttyl Joel

also have a friend set up to nerrow rearend's
 

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If you do this yourself without a jig be extremely careful to get the housing ends welded on perfectly straight.

The first time mine was done, notice I said first time, I thought I'd save a little money and a guy at the dragstrip said he could do it for $150. This was about $100 cheaper than the quote I got from a professional chassis shop. After I trashed about $100 worth of special order Moser wheel bearings due to the fact the ends were welded on a few thousandths to the crooked side, I had to have it redone, this time by a professional on a jig.
 

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I considered doing this on my own but Im still looking for a good shop to do it.

While we are on the subject has anyone tried cutting the ends off with a plumbers pipe cutter. Should give a very straight cut.
 

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Discussion Starter #10
How about removing the axle tube from the carrier, hacking off said amount then reinstall into housing,would that be easyer to keep the tube straight?

Thanks for all the help, Dave.
 

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How about removing the axle tube from the carrier, hacking off said amount then reinstall into housing,would that be easyer to keep the tube straight?

Thanks for all the help, Dave.
Sounds like more work and I dont think it will be any straighter. Main thing to be concerned about is welding the ends on straight since welding will cause some movement.
 

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You guys realize that Moser does this in-house for like $100, right?

By the time you figure out jigs, and tube ends, plus your welding supplies (and time), not to mention the risk of warpage or uneven welding, you've got at least that much in it if not more.

Of course, you have to come up with new, shortened axles (which you have to do anyway) and I think those were an additional $250 from Moser (nothing HD there, just good axles).

I'm all for DIY, but Moser did this so cheap it just didn't make sense to try and tackle it myself.

My total bill for the job was right at $350, but I do have the good fortune of living within driving distance of Moser, so I did not have to endure shipping.

Just food for thought.

J
 

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My total bill for the job was right at $350, but I do have the good fortune of living within driving distance of Moser, so I did not have to endure shipping.
Key word is you live driving distance from Moser. Shipping a rear end isnt cheap. Im looking for some local places but I dont think they will be cheap.

Moser seems to be one of the few places that will do it cheap.
 

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Discussion Starter #14
Ya shipping from idaho would kill me.
Joel thanks for the heads up on the 8in but i would like to keep this all chevy,don't know why just think its right.What would your body charge to shorten?
 

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I've done it before with a sawsall and stick welder. You don't need a fancy Jig, just alot of patience to measure twice and cut once...... Or measure many times, cut, measure many times again, tack, measure again, weld, measure again, weld some more...

Go measure any stock axle out their now and see what their tollerances are, you have plenty of room.

If your burning up bearings or something you probably have some other problem going on other than the axle being warped a few thousands.
 

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Discussion Starter #16
I think I'm just going to pull out the old sawzall and welder and get it done:devil: The rear end only cost me $60 from the local pull and save.

Thanks for all the help,I'll let ya'll know how it went. Dave.
 

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It might be easier (and cheaper) all around to just start with a correct width diff to begin with. I *think* some 7.5" S10 diffs are the right width, and the Versailles (ford) 9" with discs is correct too.

Or, find someone with a 1st gen Nova diff for sale. Pretty sure I saw a couple go by in the FS area here on the site.

If you have the stock 4-lug diff, and all you're trying to do is go to 5 lugs, the cheap way out is to take the axles to a machine shop and have them drilled for 5 lugs.
 

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Discussion Starter #18
Well the stock 4 lug was welded, no fun on the street.
So is the 2x4 s10 rears shorter then the 4x4? I keep hearing that it is but no real mesurement.
 

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If your burning up bearings or something you probably have some other problem going on other than the axle being warped a few thousands.
Mine worked just fine...at first. It would eat up an axle bearing about every six months for a couple years, then I got sick of it. Met a guy who worked for a chassis shop and he agreed to fix it for me. He put it on a jig and measured how far off it was. It wasn't much but ever since he fixed it six years ago I've been using the same axle bearings. Not saying this can't be done without a jig but speaking from experience, it doesn't take much to make your life a living hell.
 
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