12 bolt question

[68shortwide]

Hey guys, quick question. I'm assuming my truck has a 12b truck rear in it. Whether It is 5 or 6 lug I'm not sure. I'm in a situation where the truck was given to me in may from a family friend and I've never really gone over the truck like id like. So my question is, for my build I'm going with a 3.73 posi rear. Would I be better off buying a whole 12 bolt assembly from say moser or strange or Currie or just buy the gears and axles and keep my diff housing? Thanks yall

[Grumpy old man]

I would guess your best bet would be to find out what you have to start with ?

[68shortwide]

Well grumpy ya seen what I'm startin with. You've seen the pics. I havnt had the time to go down and see it. Its sitting in said friends back yard 45 miles from me. I don't have time after school and my weekends have been filled with either marching band or working on the Camaro.

[Grumpy old man]

Well ... I think you should just sell it to me and I'll rebuild it ?

[68shortwide]

Lol. Nah I've got around 3k in parts for it. Mainly suspension stuff as I haven't seen the body up close. Really what I know about the truck is that's its a 68 lol so I've just been gettin stuff that's not rel specific. After the 18th I have every Saturday and every weekday after school to go get it and bust some ass on it. I just need a plan as to what I need and where to get it. Hence the thread.

[hugger6933]

well, Jack I know you said you haven't had time to go over it much and it is not with you have you got any pics of the truck in witch you can see the wheels? Count the lug nuts that will tell you 5 or 6 it is that simple. You won't need anything from the guys at Currie or Moser unless it is change over axles and that is only if you HAVE to change the lug count due to wheel availability and that is pretty unlikely. Your diff housing unless damaged by a wreck that is possible but unlikely as well can handle anything your gonna throw at it unless your planning on much over say a 1,000 HP. I didn't think so either. Now don't get me wrong I am NOT knocking the Moser or Currie Companies they are both great and I have used them both[tops in the industry,IMO] but that is money that could be spent elsewhere on your project. Now on the 3:73 gears I think they are good but if your not running a overdrive and also plan a lot of riding [and what school age young man isn't?] I would go with a 3:42 instead. Jim

[Ozzy2013]

Could be a dana 44 thats whats in my 68 GMC

[Fitz]

Originally Posted by 68shortwide

Hey guys, quick question. I'm assuming my truck has a 12b truck rear in it. Whether It is 5 or 6 lug I'm not sure. I'm in a situation where the truck was given to me in may from a family friend and I've never really gone over the truck like id like. So my question is, for my build I'm going with a 3.73 posi rear. Would I be better off buying a whole 12 bolt assembly from say moser or strange or Currie or just buy the gears and axles and keep my diff housing? Thanks yall

Take the pics below, go crawl under your truck and pick the diff cover that matches the outline in the pics. ID problem solved.

[68shortwide]

Fitz I wish it was that easy and I have that chart memorized over the years lol trucks 45 miles away until the 20th at the earliest.

Hugger I don't have pics of the wheels. And since I'm planning an ls swap I am runnin an od trans. That's why I'm goin with a 3.73 rear, it gives a good launch and still can keep the revs down on the highway.

Anyone who wants to see pics just add me on fb as I can't post pics from my phone. Pm for add

[Elliot949]

Well a Standard 12 Bolt GM rear end is going to handle at least 400 HP/ 400ft Lb of Torque just fine... now if you are going for a crazy amount of HP and Torque then you may want to look at a Performance Differential...

[Ozzy2013]

Not to steal the post but whats a dana 44 good for as far as hp?

[68shortwide]

Originally Posted by Elliot949

Well a Standard 12 Bolt GM rear end is going to handle at least 400 HP/ 400ft Lb of Torque just fine... now if you are going for a crazy amount of HP and Torque then you may want to look at a Performance Differential...

its not a question of will it hold up its just mainly do I buy a whole assembly or just the gears and axles. Also going front and rear disc brakes if that matters in the decision. I don't know at this point if its leaf or coil overs. I'm hoping to run down next Sunday and see it up close. And bring it home two weeks after that.

[68shortwide]

And guys I appreciate all answers. Seriously. I've grown up around cars and I know a lot. But when it comes to this kinda stuff I turn to the experts. Y'all. Throughout being on the forum I've been careful about how I say things. Its real easy for something to be taken the wrong way when not face to face. Without you guys I probably wouldve given up and passed on the truck, just due to inexperience. Anyway! Enough with the sappy stuff! Next answer!