gear swap ?

[kleedus]

i have a front dana 60 and a rear 14 bolt with 4-10 gears the dana 60 has a arb locker in it and the rear has a detroit locker

i want to drop the ratio to 456 gears and need to know if my arb will work for the 456 gears. the rear is not a real big deal if i have to change the carrier the detroit can just be swapped to the new carrier but the arb is my concern.

i just dropped alot of money locking these axles and was planning on getting a 203/205 doubler and running 38'' tires. but now i am running 44'' tires and think i will need lower gears than 4-10

will the 4-10 arb work with 456 gears is my question

 

[HotRodPC]

I am almost certain on the 14B FF, that the cut off is 4.10 and down to taller gear, and then 4.56 and up for shorter gear. Honestly, for the big bucks you'd spend to do this for not even a half of a turn or broke down like this to put it into perspective for you, There is 8 half turns in your 4.10's and going to be 9 half turns in your 4.56's, break that down into a percentage, it's about 11-12% lower gear, I woudln't even consider spending the money. If it's broke, don't fix it. With an ARB up front and a Locker in the rear, you've got the ultimate set up IMO. I'd leave it alone as is and be happy as a pig in poop with the 4.10's. JMO.

 

[HotRodPC]

BTW, The doubler would be where to spend the money for the best gain. What transmission are you running? I just don't see the benefit from 4.10 to 4.56. With 44's you might consider 5.13 or 5.38 gears, but I'm farily certain, you'd have to buy new lockers.

 

[kleedus]

ya thats what i am afraid of i was just hoping to go lower gears with what i have already bought

the truck these are in is my mud truck its a 83 blazer chassis with a 64 chevy body it will have a 500 horse 454 turbo 400 205 combo for now till i can get the doubler

i may just have to start over with another set of axles and get a new arb and a rear carrier for the lower gears

i do have another set dana 60 14 bolt just not looking forward to dropping that much money down for a new arb

my thinking is to keep a mellow axle gear and let the doubler do the work its not a rock crawler so i wont need a way low gear
in the mud i will need the wheel speed without having to run my motor on the red line of the tach constantly

 

[HotRodPC]

Yeah, I think I'd just keep the 4.10's and go for that doubler. One thing nice about that disadvantage of the NP205 and not quite a full 2.0 crawl ratio, for the purpose of easy math, if its just a mud truck, run that thing in 4 Lo, and it would be equal to running 8.20 gears in the rear end with those 44's. Then when you need that deep crawl ratio, the doubler will give you the Lo doubled again, equal to 12.30 to 1 in the rear end with the doubler. That's pretty damn deep. To keep the lockers and not spend another fortune on lockers and new gears, I think I'd just do the doubler and call it good.

 

[bucket]

I wouldn't mess with changing ratios if your only going to bump it one notch steeper. I'd go with 5.13's or even 5.38's with 44's. Correct me If I'm wrong, but 4.56 gears are available for the 4.10-down carrier, I'd assume the same is true for 5.13's.

 

[HotRodPC]

I wouldn't mess with changing ratios if your only going to bump it one notch steeper. I'd go with 5.13's or even 5.38's with 44's. Correct me If I'm wrong, but 4.56 gears are available for the 4.10-down carrier, I'd assume the same is true for 5.13's.

I woudn't swear without looking it up again, but I think it's 4.10 and down numerically, and 4.56 and up numerically is the cutoff. Then, you can get 5.13's for either or. C4 should know for certain. He just regeared his truck with 5.13's but now that I think about it, I beleive those 5.13's for the 4.10 up carrier was for Front Dana 60 only. Now I'm confusing myself.
As I said, and bucket obviously agrees, I wouldn't do the 4.56 swap from 4.10's. Just not much gain for the big expense.

 

[bucket]

I woudn't swear without looking it up again, but I think it's 4.10 and down numerically, and 4.56 and up numerically is the cutoff.

You're right. But I think you can get 4.56 gears for a 4.10 and down carrier, through the aftermarket. The ring gear is thicker.

 

[HotRodPC]

You may be right. I know you can get 4.56 in 2 different thicknesses.