Squarebody Differentials.

[bucket]

Right, no K30's before '77. IIRC, it even says "The new K30" in the '77 brochure.

 

[4thgentruck]

Ok this may be a dumb question but what does corporate mean? And what would my 12 bolt out of my.77c10 be?. It origionally had the inline 6 in it.

 

[HotRodPC]

Ok this may be a dumb question but what does corporate mean? And what would my 12 bolt out of my.77c10 be?. It origionally had the inline 6 in it.

Not a dumb question. It's GM Corporate. Meaning GM made their own. It's not a Dana brand, or Eaton brand like other Truck manufactures use. Your 12 bolt will be a GM Corportate Truck rear end. Probably the best choice for a stock to mild performance powertrain on street tires.

 

[4thgentruck]

Oh ok i got you. Thats why I love this forum constantly learning stuff. Esp right before my ground up resto. I know you do alot of commenting on alot of post and quite a few of mine. Ty

 

[Rollin_Thunder]

So how much HP and TQ can a stock 14 bolt corporate handle? I'm planning on a 600 HP 1,000 TQ Cummins.

 

[HotRodPC]

So how much HP and TQ can a stock 14 bolt corporate handle? I'm planning on a 600 HP 1,000 TQ Cummins.

Go For it !!! Try to break it. Let us know if you can !!!

 

[HotRodPC]

Doh, Wait a minute... Are you talking Full Float of Semi Float?? Go with the Full Float 10.5 inch.

 

[Driver4r]

What 12bolt carriers can hold up to 4.88s?

 

[HotRodPC]

Are you asking as in what brand, or what the cut off is for gear ratio? All brands will hold up to 4.88 gears.

Usually in 12 bolts in both Passenger Car and Truck 12 bolts, it's going to depend on the the deck height on carrier. In a Truck, you're probably looking for a 3.73 and up, as in up numerically, but lower in gear ratio. All depends on where the carrier carrier break is. For 12 bolt trucks there is 3 different carriers, and also for 12 passneger cars there is 3 more carriers.

 

[Rollin_Thunder]

Go For it !!! Try to break it. Let us know if you can !!!

Ok. I'll give it a shot. Are full floating stronger?

 

[HotRodPC]

Ok. I'll give it a shot. Are full floating stronger?

Sure enough. Go ahead. Just do it. Try to break it. It'll hold up just fine. Provided it's in good shape, and most are up to about 500,000 miles or more if kept full of good oil, you'll break a transmission or transfer case before you break the rear end in a 14b Full Floater. Yes, the Full Float is stronger. About equal to a Dana 70.

 

[Rollin_Thunder]

Well that's good to know. I'll have to make sure it's a full floater.

 

[HotRodPC]

Well that's good to know. I'll have to make sure it's a full floater.

If it's a K30 then it already is. 3/4 ton came with either 14bolts in the 80's.

 

[elstm3]

well i would try to avoid the gov-loc diff in the 14 bolt. get an open diff and get a TAD

 

[HotRodPC]

well i would try to avoid the gov-loc diff in the 14 bolt. get an open diff and get a TAD

I agree. I'd TRY to avoid the G80 Gov Lok aka Gov Bomb. But, if it's what you have right now, then I'd just go with it. The Gov Lok in 14B Full Floats is apparently stronger than the other Gov Lok models. And when the Gov Lok breaks, you've lost your locking diff feature, but you're not stranded with a broken gov lok. It'll work like a standard open diff. Bad thing about the Gov Lok, it is what it is and you can't install your own limited slip or locker or your choice without swapping to an open carrer first.