Swaping out rear end

So i am having to take my rear end off as my e break snapped off and wrapped around my axle completly distroying my axle housing. So my question is what do i need to look for when picking another rear end from a salvage yard?

Im asuming that i will need another with a rev-loc limited slip differential to put into my truck and im also asuming that if i find a truck with the same stuff in the rear end and its the same year i wont need to figure out my gear count. Please correct me if im misstaken

I don’t have a definitive answer for you. But usually trucks have various optionable Rear ended ratios. As far as limited slip, do you need it? That might limit your options.

Perhaps you could have your rev-lock transferred into a replacement rear ended housing.


I wasnt sure if a housing without rev-loc slip differential would have the space for one.

And yes sadly its a must have i live on a road that is pure clay. I dont think i would ever make it home with out it

The axle housings are the same for rev loc and open diffs. You need to look for the correct axle ratio and a rev loc. Salvage yards will list the range of years snd models that have an axle that will swap into your truck. And you DO want to swap the whole axle assembly complete. It is the easiest, cheapest and most reliable way to fix this.

You will usually see something like … 88 to 93 Chevy 1500 pickup, 3.45 posi, drum brakes listed

GM made millions of half ton trucks, there is a used axle out there for you.

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While the locker and open diffs both fit in the same housings, the housings were different between 2wd and 4wd. You likely have an 8.5" ring gear axle, though there is a slight chance it is a 9.5". Count the number of bolts on the diff cover. 10=8.5", 14=9.5".

Look for the rear axle option code in the RPO list that should be in the glove compartment. Possible options include GU2, GU4, GU6, GT4, and GT5 (these codes give the gear ratio). G80 is for the locking diff. The option code for your truck, along with whether 8.5" or 9.5" and 2wd or 4wd is all the info a salvage yard should need to match it up.

There may also be a tag under one of the diff cover bolts that gives pertinent info.

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I’d sure want to replace the whole axle, and not try to swap out the parts. That can require special tools and setting exacting clearances .

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To get the Ratio of a rear end, put a horizontal chalk mark on the driveshaft and jack up one rear wheel or if the wheels are gone, one side of the axle housing so one wheel can turn and the other can’'t.

Mark the wheel or axle with chalk and turn the free wheel two full turns while seeing how many rotations the driveshaft turns, 3 and 1/4 is 3.23, 3and 1/2 is 3.55 etc.