Gearing axles bla bla bla

[OrlandoSonomazr5]

So i've been trying to figure out this whole rear ZR2 axle swap thing


Right now I have a 3:73 rear end with locker. Does that say anything about my front diff. And do I will I still benefit from the zr2 axle swap which I believe is just wider correct?

[RobsZRinAR]

Hi Orlando. I'm researching the same Q? myself and believe that as long as you stay 3:73 in the rear, it will jive with the front end. These have to match on BOTH ends.
You are correct that the ZR2 axle length is longer. It's not a 'fitment' problem from what I understand. Plug & Play?
There's a cool thread on here, somewhere, with more info. Did you look under the Mods tab on the homepage??

[_STUCKY]

I haven't personally done this swap, but as far as I know it should be a straight swap. May need a conversion u joint, may need to swap your brakes onto the new axle, but as long as you have a 3.73 geared truck, you are good to go. The zr2 axle has a bigger ring and pinion, I believe bigger axle shafts, and are a little bit wider. It's a pretty good upgrade if you are keeping the ifs front.

There's a good thread somewhere on the subject. Also somewhere is a list of the rpo codes in the glove box. I'd double check the gear ratio at the axle instead of going off the glove box.

[OrlandoSonomazr5]

Original owner was my mom so I have the window Decal from the dealership. Its definitely locked 3:73's, but its good to know the info straight forward

I've decided to keep my sonoma mostly stock and im building a Jeep XJ with a LS instead.

[ApproachMedium]

I did the zr2 swap on mine, because my axle was having some slight misbehaving with the V8 attached. I think after 270k+ it wasnt happy anymore. My zr2 axle came out of a pickup and was a direct swap. zr2s will have disc brakes on all of them if i recall, so swapping brakes is not necessary. I did on mine though because the zr2 had stock GM rotors and calipers while my axle had fairly new napa premium stuff.

[Torskdoc]

Axle swaps on the blazer/trucks are basically plug and play. The biggest thing is to check the RPO for the gear ratio. the pinion gear went in my 95 Jimmy (after humming for 119,000 and a few x-country trips). The Jimmy had the 3.42 in it. Went to the junkyard and found a 98 Sonoma with the same setup, and did the swap. The only thing NEW I put on was shackles. The lack of bumper mounts on the sonoma axle was rectified with some rubber blocks shackled to the axle. I was looking to do a straight 98 or newer disc brake axle swap but all the trucks/blazers that had disc brakes all had rotted off bcking plates and I didn't have the time to go looking for a good set, so I settled for drums.