A Body 12 Bolt in a G Body? The Ultimate Improvement for the Rear End!

The El Camino has reached a crossroads, the 7.5” 10 is on its last legs and is about to leave me with a pile of broken parts and a car that’s very hard to move. So that leaves me with options, rebuild the 10 bolt for the 4th time, or upgrade it with a 9” Ford or something else that won’t break. As luck would have it, I met someone local that would have my solution and even had it under another G body. So I knew that this was going to be a great option.

The solution came in the form of a very well built 12 Bolt from a 1970 Chevelle. This 12 bolt came to me with C Clip eliminators, 35 spline Moser axles, 4.11 gears, Spool, Lakewood Anti hop bars with several points of adjustment, and all the parts to make this work under my El Camino. This was from someone that I met racing at Flying H Dragstrip, it’s always a good idea to take time and build relationships that matter.

So, this 12 Bolt already has given me a slightly unfair advantage in being practically set up. I started to remove the nearly broken 7.5” 10 bolt and it hit the ground and came out from under the car without much drama, I was able to undo the hardware and pretty much everything fell out.

I had previously used upper and lower control arms from Dick Miller Racing to run the upper control arm relocation brackets, which actually had double adjustable upper control arms that were a really good fit for this new set up. The offset was nearly right with the Lakewood anti hop bars and my upper control arms.

When it came to the driveshaft, the original G body uses a 1330 style U joint and the pinion yoke on the 12 bolt is a 1310 set up. Napa has a conversion U joint under the part number UJ372 that adapts this over. I didn’t step up to a 1350, because that would need a new driveshaft, transmission and pinion yoke. It’s on my list to make this upgrade, just not right now. The Conversion U joint was $35 vs who knows what it would cost the other way. 

After the U joint was taken care of the rest of install went pretty smooth, the geometry was set up to match what I had,  and the brakes were bled leaving me with a car that now moves and stops. I’m looking very forward to getting this car back out to the track to see how this new 12 Bolt works out!