what gears should I run in my 3/4 ton lifted gmc?

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ruedger455

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Well thank you for the great advice. So your saying that the 4.56s will probably be my best bet.
 

HotRodPC

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Well thank you for the great advice. So your saying that the 4.56s will probably be my best bet.

I'm actually saying any one of the 3 would be good for you, depending on the cash you want to spend or not spend. Cash not being a big issue, for you, yes the 4.56's would be good. You're not doing much highway speed driving, and running a tall tire.
 

ruedger455

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Yea I found a 4x4 shop that is close to me that will do the swap with g2 gears for 1400 out the door for both axles.
 

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If you're willing to spend $1400 for regearing, I'd do some shopping, watching and waiting and you can find a set of 4.56 CUCV 4.56 axles for that money. That's including a Dana 60 for the front and a Detroit Locker in the 14b Full Float rear axle. Those will bolt right into your truck and then you have the best of the best. Most of those CUCV's are also fairly low mileage considering they're 30 year old trucks.
 

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All this gear swap really will do for you is keep you higher in rpm (after your cruising) could be in your rpm band where your engine shines. What I would do is post up your cam specs so we can give you good gear set to go with.
 

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If you're willing to spend $1400 for regearing, I'd do some shopping, watching and waiting and you can find a set of 4.56 CUCV 4.56 axles for that money. That's including a Dana 60 for the front and a Detroit Locker in the 14b Full Float rear axle. Those will bolt right into your truck and then you have the best of the best. Most of those CUCV's are also fairly low mileage considering they're 30 year old trucks.

want to know why 80% of cucv trucks had such low miles, and most cucv blazers had higher miles? because the trucks had 4.56 gears and would scream anywhere they would go, so they resorted to driving the 3.08 gear blazers


but back on track, hotrod is right you can find a set of cucv axles for cheap, and between you and me some cucv sets of axles had a Trac lock posi front as well as the Detroit in the rear
 

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want to know why 80% of cucv trucks had such low miles, and most cucv blazers had higher miles? because the trucks had 4.56 gears and would scream anywhere they would go, so they resorted to driving the 3.08 gear blazers


but back on track, hotrod is right you can find a set of cucv axles for cheap, and between you and me some cucv sets of axles had a Trac lock posi front as well as the Detroit in the rear

You're right and right again. Those 6.2 Diesels didn't like those 4.56's at all. And yep, some of the CUCV's did have Trac Lock Limited slip in the front, and all the rears had Lockers.
 

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