New locker what gear?

[KySilverado]

Guys, got a Detroit Truetrac in the garage. Figure I'll up the gears while at it. Being 4wd obviously double the trouble and cost so important to do it right. Presently 3.73's. Leaning toward 4.10's but 4.56 not out of the question. Not to many running 4.56's, guys that I have talked to say they can't hook them on street tires with similar power as mine even in 4wd. Wondering if anyone here has any experience with 4.56 in a 4wd for a track setup.

[daredevil350]

I would think 4:56's would be pretty good for your application. If you are concerned that it will turn your truck into a smoke machine go w/ 4:10's. But I think 4:56's would be a solid choice.

[RedHeartbeat]

Depends on tire size, anything under 32s go with 4.56, over 32s go with 4.88s.

[91_bowtie]

What size are your tires? What rpm are you hitting the traps at?

[KySilverado]

<div class='quotetop'>QUOTE(91_bowtie &#064; Dec 26 2006, 11&#58;20 AM) [snapback]77354[/snapback]</div>

What size are your tires? What rpm are you hitting the traps at?
[/b]

285/50/20 - 31.2" diameter. Trap about 4200 rpm now. With 4.56 about 5200 depending on wheel spin at the bottom end. More into the HP range in 3rd no doubt. On paper with the 4l60E gear ratio&#39;s and OD the 4.56 do look good. Still plenty of RPM to pull topend for a truck. Cruise 65 -70 mph in OD about 2500 rpm. Not to mention how much fun it would be to drive around town and have instant smoke on tap, probably anywhere through second gear.

Still its all about 1/4 mile improvements in a street trim. I have my doubts that I could hook 4.56&#39;s on street tires. I would probably loose E/T due to wheel spin.

[91_bowtie]

<div class='quotetop'>QUOTE(KySilverado &#064; Dec 26 2006, 12&#58;11 PM) [snapback]77364[/snapback]</div>

285/50/20 - 31.2" diameter. Trap about 4200 rpm now. With 4.56 about 5200 depending on wheel spin at the bottom end. More into the HP range in 3rd no doubt. On paper with the 4l60E gear ratio&#39;s and OD the 4.56 do look good. Still plenty of RPM to pull topend for a truck. Cruise 65 -70 mph in OD about 2500 rpm. Not to mention how much fun it would be to drive around town and have instant smoke on tap, probably anywhere through second gear.

Still its all about 1/4 mile improvements in a street trim. I have my doubts that I could hook 4.56&#39;s on street tires. I would probably loose E/T due to wheel spin.
[/b]

hmm... I&#39;m running 28" tires, and I trap at 5000 rpms, with 3.73&#39;s. I need to verify the tire size used in the tune though, because it was a little off at the time.

I don&#39;t see how you could hook with the 4.56&#39;s on street tires, but it&#39;d be nice to have the neck-snapping ability. I&#39;m getting drag radials this spring, so I&#39;m considering a gearing upgrade at the same rime. I&#39;m interested to see how this works for you. I think 4.56&#39;s would be insane.

[KY_BOB]

I don&#39;t have a problem hooking up with 4.56&#39;s and street tires but I&#39;m not making as much power as you, especially on the bottom end. I&#39;m also on 33/12.50 tires.

[KySilverado]

<div class='quotetop'>QUOTE(91_bowtie &#064; Dec 27 2006, 01&#58;57 AM) [snapback]77436[/snapback]</div>

hmm... I&#39;m running 28" tires, and I trap at 5000 rpms, with 3.73&#39;s. I need to verify the tire size used in the tune though, because it was a little off at the time.

I don&#39;t see how you could hook with the 4.56&#39;s on street tires, but it&#39;d be nice to have the neck-snapping ability. I&#39;m getting drag radials this spring, so I&#39;m considering a gearing upgrade at the same rime. I&#39;m interested to see how this works for you. I think 4.56&#39;s would be insane.
[/b]

A lot of guys on other forums are telling me to go 4.10&#39;s and do a track setup with smaller tires/wheels to change final drive ratio. You can see the difference between ours with just that small change in tire diameter. 4.10&#39;s would probably be the most you would want to do with those short tires.

I&#39;ve always been a little conservative with my choices. 4.56&#39;s would be a little to the wild side&#33;


<div class='quotetop'>QUOTE(KY_BOB &#064; Dec 27 2006, 12&#58;41 PM) [snapback]77476[/snapback]</div>

I don&#39;t have a problem hooking up with 4.56&#39;s and street tires but I&#39;m not making as much power as you, especially on the bottom end. I&#39;m also on 33/12.50 tires.
[/b]

This is becoming a damn tough decision. I have my mind set one way. Like 4.10&#39;s today and then guys like you come back and say "hey, I hook 4.56&#39;s".

You are right though, I probably make a little more power down low and those big ass tires and wheels you have. Put some stock tires and wheels on it sometime when you go to the track&#33; Think you would like it.

[KY_BOB]

<div class='quotetop'>QUOTE(KySilverado &#064; Dec 28 2006, 07&#58;39 AM) [snapback]77555[/snapback]</div>

You are right though, I probably make a little more power down low and those big ass tires and wheels you have. Put some stock tires and wheels on it sometime when you go to the track&#33; Think you would like it.
[/b]

I would love pick up a used set cheap. I&#39;m myself for selling my stockers.


One more thing about me hooking up with 4.56&#39;s, I&#39;m 700# heavier than you, (6100#+).

[KySilverado]

Going 4.10&#39;s. I bought a complete front NOS differential with 4.10&#39;s yesterday on ebay. Considering the cost of gears, install kit and the cost of having them installed or installing them myself I broke even or maybe saved a few bucks.