The Stovebolt Site Forums The Shop Area Engine Shop swapping 8 lug front end for 6 lug

okay, as many of you have done, I have a 66 3/4 ton 8 lug pickup that I need to make 6 lug. the rear end is an Eaton HO52 which NO ONE makes a ring and pinion for. Had I known that I might have waited for a 1/2 ton. It is currently a 4:56 ring/pinion. Not going to work as a daily commuter. I purchased a 12 bolt rearend from a 70 Chevy pickup with 3:07 rear end I am going to swap in soon.
first question, this looks like a direct bolt in, with exception of the panhand and driveshaft. Do I need to lengthen the driveshaft, if so how much? What will this swap entail?
second question and more importantly, what does it take to convert the front end to 6 lug? I do not want disc brakes. I was told that the easy thing is to swap out the whole front member, but I just dropped in a engine and tranny and do NOT want to pull it back out. Can I just run 1/2 ton spindles? Will my 3/4 ton ball joints work?
ANY info regarding the rear end swap or front end swap would be greatly appreciated! Any tips or time savers for me? Have a baby coming in 6 weeks and am trying to button this thing up. If nothing else, I am going to get the rear end in so I can drive it to work and back, and still keep the front 8 lug.
Thanks again fellas!

Driveshaft is not a problem, whatever needs to be done with it.
Install the rear axle and measure to see what you need. If the original driveshaft is to long or short take it and your measurement to a driveshaft shop and have the work done, also have it balanced too.

Grigg

Thanks Grigg,
might be tackling this thing over the 4th of July weekend!

The complete IFS crossmember will swap from a '63 to '87. Disk brakes started in '71, so you need a 1/2-ton '63 to '70. It APPEARS to me that they 1/2-ton, 3/4- and 1-ton all mount exactly the same, though I've never swapped them.

The crossmember is 14 bolts, but the motor mounts sit on it too.

I don't think there is an easy fast way to do this swap without a parts book in front of you to make sure things match up. Best bet would be to go to an online parts supplier and start comparing part numbers.

If the ball joints have the same part number you know you can swap the spindles... That kind of approach.

Anything short of the entire crossmember and you'll be dealing with the springs. Unless you have a spring compressor it might be easier to do the entire crossmember.

I'd suggest if time is limited you do one end at a time...

Balljoints are different, most likely in the stud sizes on the upper. Lower may have a different housing size, may need to measure the size to make sure it will pres into the control arm. Numbers (Moog) are K6024 Upper, K6023 Lower. 3/4 ton uses K680 Upper, K6025 Lower. Those numbers are for drum brake trucks.

Or you can put a 3/4 ton rearend out of a 1976-1981 chevy truck. Most of those came with 3.73 gears that are more highway frendly. This is what I am going to do to my 1946 chevrolet 3/4 ton It also has the same HO52 Eaton with 4.56 gears.