Looking for new rearend...for truck:)

[pcmcobra]

I currently have an 86 silverado that has a 10 bolt w/ 2.73
I want to put a 12 bolt w/ 3.73
What year axle assy will bolt right up? Have been searching the "boneyards" for donors.
Just wanted to know what to look for.
Actually, a 12 bolt will do, I can buy the gears I guess.
thx all.

[piecesparts]

We put a 12 bolt rear axle from a 79 Chevy four wheel drive under my Son's 86 two wheel drive truck and took out the 10 bolt. The axle had 3.73 gears with a posi carrier. We had to replace the axles with five bolt axles and then later wwe updated the carrier to a new Eaton unit, because of a cracked center plate in the posi. The axles interchanged directly and I just put new brake shoes on the replacement axle, that way all I had to do was unbolt one and slide the new one into it's place. The driveline had to changed in length, since the carrier housing on the 12 bolt is slightly different length, than the 10 bolt.

anyone need a complete 3.08 geared 10 bolt with good brakes and drums?

[lilpup69chevy]

any 73-81 12 bolt 1/2 ton rearend for a 2wd will work and like piecesparts said you can use a 4wd rear if you switch the axles, lot of the 73-81 trucks 2wd in the junkyards with the 12 bolt, the reason why i say 81 i know its the different body style as i have one but mine has the 10 bolt but i have heard that the 12 bolt was available in 81 as well i know it was offered until 80 cuz my 80 stepside had the 12 bolt factory with 3.73 gears

[HOGDADDY]

FYI all Chevy 12 bolts aren't created equal and I am referring to cars vs. trucks. The truck 12 bolt is not the same HD rear that comes in pass. cars. The pinion diameter is smaller than that of a 10 bolt rear and some people don't believe they're as strong as a 10 bolt rear. I would just put in a new set gears in that 10 bolt if it were mine screw the 12 bolt. jmho.

[ocbaud]

Originally Posted by HOGDADDY

FYI all Chevy 12 bolts aren't created equal and I am referring to cars vs. trucks. The truck 12 bolt is not the same HD rear that comes in pass. cars. The pinion diameter is smaller than that of a 10 bolt rear and some people don't believe they're as strong as a 10 bolt rear. I would just put in a new set gears in that 10 bolt if it were mine screw the 12 bolt. jmho.

qft

we had this discussion a couple years back when i was more frequent on here. the car 12bolts are about as strong as a 9inch.

here is what i remember:

the truck 12bolt has a smaller pinion diameter but has larger axles than the 10 bolt.

[Slonaker]

I was considering a swap to a 12 bolt (same gear ratio, non-posi just like my 10 bolt) when a member offered me one for free. I talked to a friend about it. He is a GM mechanic, and he owned a junkyard back when these trucks were new. He said that the 12 bolt is no stronger, the swap would not gain me anything, and that parts for 10 bolts are more available i junkyards if I ever break something like an axle. I stuck with what I have.

Slonaker

[Captkaos]

If you are switching from a 10bolt truck to a 12bolt truck for strength reasons, you are wasting money. They are just as strong. Just get a new set of gears.

[pcmcobra]

thx for the advice!
I'll stick with the 10 bolt and just swap gears.
thx all!