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4.10s to 4.56s?

4.10s or 4.56?

  • Keep the 4.10s

    Votes: 8 72.7%

  • Upgrade to the 4.56

    Votes: 3 27.3%
  • Total voters
    11
  • Poll closed .
Chevy305

Chevy305

6 Lug 14bsf Status
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Posting this thread as the "Might as Well" has gotten to me. I need to tear down the front axle on my truck and replace the inner axle seals and pinion bearing and yoke. So I figured I'd do ball joints while it was all apart. Well I have all those parts waiting for when the truck comes out of storage in the spring. In this downtime I'm my own worst enemy and have been contemplating when its apart swap to 4.56 gears. I'm trying to decide if its worth it.

It's not a big gear change but it'll net me about 200-250 rpm on the highway. The current setup is a built 355, NV4500, 4.10s and 35" tires. Its a good setup and works well but I've been thinking a little more gear would be nice when starting out in 2nd and a few more RPMs will make 5th gear a little more useful around town. On the highway, I currently turn about 2000 rpm at 70mph with the 4.10s. With 4.56s that'd be more like 2200rpm which is a little more in the engine's sweet spot. If money was no object, I think the choice would be easy, but pricing out gears and install kits for a front 10bolt and rear 14bsf is running in the neighborhood of $5-600. That's enough to make me hesitate and really think, is it worth $600 for a few more rpms? Help me decide.
 
I would at least consider 4.88s also. 11% vs 16%.

IMHO your truck is to that dailing it in stage. I do think the investment is worth it
 
say it again

if over drive go DEEP 5.13 if over 35" tires . that's what over drive is for .

you prob wont even notice a difference in 4.10 to 4.56 other than time / money gone .

play with this . http://www.grimmjeeper.com/gears.html

and doing deep gears in 1/2 tons is waste of time if you go off road at all. or beat on stuff a bit . pinion gear to small and rips apart under heavy use .
 
It's a SF 14 in the back. So for a mild off roader I think he is set axle wise.

I do agree though you really need to investigate everything above your current gearset
 
about 250 rpm at 70mph the board with 4.10 - 4.56 swap .

and 4.10 - 4.56 is 194 more rpm at 10mph 2nd gear .

and 4.10-5.13 is 300 rpm at 10 mph 2nd gear . and just under 500 more rpm at 70 mph .
 
Easy guys, I'm not going 5.13s or even 4.88s this truck is far more mall crawler now than off roader. I made it too pretty... :doah:

Yes its a 10b front with a lock right and a 6 lug 14bSF rear with a Detroit. I'm not interested in swapping axles either. I've already got too much into these.


I'm just looking for your opinions on whether this slight gear change would be worthwhile enough to justify the money.
 
Chevy305 said:
Easy guys, I'm not going 5.13s or even 4.88s this truck is far more mall crawler now than off roader. I made it too pretty... :doah:

Yes its a 10b front with a lock right and a 6 lug 14bSF rear with a Detroit. I'm not interested in swapping axles either. I've already got too much into these.


I'm just looking for your opinions on whether this slight gear change would be worthwhile enough to justify the money.
Click to expand...


So is that a no on the LS swap?
 
I'm sorta in the same boat as you. Least you have 4.10s and the 4500, I have 3.73 and 4L60. (barf) For now at least it will stay an auto, but needs regear BAD. I do plan to wheel it, but drive it as well. I also have 2 different tires, 35s and 38" boggers. Boggers for wheeling obviously, and don't think I'll need OD for wheeling, I guess one nice thing bout the '60 is low 1st gear. I'll be SAS'n prolly in the spring, so got time to figure out what gear to run. But it can frustrating figuring which way to go. You think 4.10 to 4.56 is a big jump, but when do the math, it's barely a couple 100 RPM. But also don't want the tach bottoming out on the highway just to pass grandma....As for swapping gears, find a good mechanic that just charges labor, not gear installs. I had gears installed in a Dana 60 (which told can be a bitch) for $100. Its good to have connections.
 
Thanks for the insight guys.

I went with 4.10s originally because I didn't have OD with the SM465. With a 35" tire that still nets a bearable highway rpm while not being a dog around town. If I had OD at the time I'd have done 4.56s from the start. But you know, our trucks evolve over time and you end up spending money 2 or 3 times on the same thing... :doah:
 
I think you made the right choice. I also have a 465 and 4.10. Was 3.73. Not a ton of difference but you do feel it some. With od I'd have gone 4.88 but one ton rear I got had 4.10 so I redid the front to match. That 600 can be used elsewhere I'm sure.
 
Chevy305 said:
Posting this thread as the "Might as Well" has gotten to me. I need to tear down the front axle on my truck and replace the inner axle seals and pinion bearing and yoke. So I figured I'd do ball joints while it was all apart. Well I have all those parts waiting for when the truck comes out of storage in the spring. In this downtime I'm my own worst enemy and have been contemplating when its apart swap to 4.56 gears. I'm trying to decide if its worth it.

It's not a big gear change but it'll net me about 200-250 rpm on the highway. The current setup is a built 355, NV4500, 4.10s and 35" tires. Its a good setup and works well but I've been thinking a little more gear would be nice when starting out in 2nd and a few more RPMs will make 5th gear a little more useful around town. On the highway, I currently turn about 2000 rpm at 70mph with the 4.10s. With 4.56s that'd be more like 2200rpm which is a little more in the engine's sweet spot. If money was no object, I think the choice would be easy, but pricing out gears and install kits for a front 10bolt and rear 14bsf is running in the neighborhood of $5-600. That's enough to make me hesitate and really think, is it worth $600 for a few more rpms? Help me decide.
Click to expand...


How about a BBC swap instead of a gear swap?

You'll pick up a lot of bottom end TQ that will make the truck feel more "lively" off the line... And 2000RPM on the highway (with your existing 4.10s) would be just about perfect for a BBC...


:thinking:

Also......think of the cookies.



-G
 
Greg72 said:
How about a BBC swap instead of a gear swap?

You'll pick up a lot of bottom end TQ that will make the truck feel more "lively" off the line... And 2000RPM on the highway (with your existing 4.10s) would be just about perfect for a BBC...


:thinking:

Also......think of the cookies.



-G
Click to expand...
Makes for a good burrito warmer as well. Lol. I vote big block now. Haha
 
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