I know that a limited slip axle is obviously superior to an open differential, but I was wondering what perks there are to having an open differential???? A friend of mine was telling me one handles better than the other but I wouldn't know. I do plan on installing a LS later on but I already have all the parts and tools to do the swap to 4.10's open. I'm just wondering if there are any upsides to not having a LS?

Thanks!

 

The only advantage that I can think of where an open diff would be advantageous over one that is not is on a situation where a 4wd truck has large tires and an undersized axle. A traction aid may put additional stress on a wheel with traction and cause some carnage, where the open diff owuld simply spin the wheel with the least amount of traction, but it looks like you do not fall into this category.
You do know that even though your rear axle does not have a carrier break, it will stil require you to set up your gears again after you buy a new LS carrier. To me doing that type of work twice is not so much fun, and wating for a LS carrier makes a little more sense.
Other than that, I can't think of any other reasons where an open diff has an advantage over a LS. (Even when the vehicle is driven in the snow)

 

Okay I have another question I didn't think to ask.

Right now my gearing is 3.08 and I can hold at over 100 MPH easily. What will my top speed be once I go to 4.10's? My motor has EFI so maybe that will help??

 

Interesting you should ask that. There has been some discussion regarding this exact topic, and perhaps we will use your truck a real world example.
My position on this, is:
You will still be able to achieve your 100 plus mile an hour runs for any period of time you wish, as top speed will not be affected by your ratio, your rpm's will be higher at that speed. You will accelerate to that speed much quicker than you did with the 3.08 gears, but not be limited by the gears.
Your driveshaft / pinion is making one more revolution per rotation of the ring gear, and one revolution will help by creating a deffinate mechanical advantage with regards to acceleration, but not be so drastic that you will be unable to turn enough rpm's.
Torque and horsepower are the results of speed. Sure there are variables such as resistance, but in your truck, the resistance variable remains unchanged since you are keeping the same tires, weight, cab heigth etc.
Your truck is turning how many rpm's now when you are driving at wide open throttle?
Does it not go faster because you are out of rpm? Its out of puppy power right? More power can push harder on the crank and turn higher rpms creating more speed.
Could you install a 2.0:1 rear gear and reach a higher speed? That answer is no, and it would take you a bunch of miles just to get the truck up to speed.
Your 4.10:1 gears will net the same MPH, simply at a higher rpm, an quicker acceleration.
That being said, we have pulled the pin on the grenade, so now lets se what other responses are available.

 

the only other advantage is if an "inexperianced" driver is driving in the snow or rain when they accelerate around a turn with a lsd the back end could and probobly would kick out and they could sping around and hit a car or run off the road where as with an open diff it would just sping the wheel with least traction but would stay controlable

as for the mph thing i use the calculators on this site

http://wildcatent.freeyellow.com/zookmods/calc.htm

to determine rpms with any tire gear mph combo

it says at 100mph with 3.08 and 29in tire youd be at 2800rpms in od assuming you have the e4od trans

but with 4.10 youd be at 3800rpms thats a big step in the wrong derection for gas mileage but if you dont care about that it should improve your acceleration

 

Alright, now armed with this knowledge I am even more eager to put the gears in. I won't be able to until after Christmas though. When I do I will be able to put my own two cents in.

Let me make sure I have this correct. Because the 4.10 gears are lower and thus raises my RPMs which in turn equals a faster tire spin and faster acceleration, right?

Okay, so if this is correct, why does everybody tell me the lower the gear the slower the acceleration? Also I have worked around and with an F550 with a Powerstoke. The beast was slow but could pull a house down. It has twice the horsepower my truck has but my truck could run circles around it. The reason is the gearing, right? So if this is true everything you said is incorrect.

I think I'm confusing myself!

 

well, if u get TOO low geared, you wil run out of rpms very quickly, and need to shift. in general lower gears will be QUICKER, but higher gears will be faster. theres a difference, in ecceleration and top speed.

ofcourse it all depends on the engine. that f550 is prob geared WAY higher than you truck. but it runs out of rpms around what 3k or less?

 

About 3K, yes. So what you're saying is although I might be able to accelerate quicker, my top speed may not be as high as it was? I like the thoughts of having a better pickup speed!

The F550 wasn't supposed to go much over 60 mph. Although we ran her at 70+.. Which is probably why the transmission gave out. We always had it redlined. What a tough truck though

 

that depends on what limited your top speed before. if it was rpms then yes you wont be able to go as fast.
if it was hp, but still had rpms left before redline, u might actually have a slightly higher top speed.
like i said, it all depends on the engine.

 

Ah, I think I understand now. Thanks!

 

see some people confuse what higher gears means so let me try to explain

lets look at what your doing going from 3.08 to 4.10

some people would call this going higher because it is "numerically" higher

but some would also call this lower because it is infact a lower ratio like when a manual trans has a "granny low" its a numerically high 1st gear

some people consider going the oppisite like going from 4.10 to 3.08 higher because you have more speed potential or better hyway gearing

kinda confusing but you should be able to understand now

 

I already understood all of that, I just wasn't sure exactly what the lower gears were going to do to my accerlation / speed. What I'm wanting to do is build a "flag ship" truck for pulling with an inline six.

Thanks to everyone for your imput, I'm sure I'll have more questions a little later! Also since I'm here, what do you all think of Uniroyal Liberator AT tires? I guess they're only sold at Wal Mart. Decent tire? Bad? What what what?

 

The pinion depth will not change by just changing carriers. He would only need to set the back lash which is simple. So he wouldn't need to completely set up the gears again. Setting pinion depth is the most time consuming thing in setting up gears.

 

LS will fish tail far easier at speed and more likely to kick out and hit a pole or tree when crawling in mud or snow at low speed,more fun and better traction.An open will use the non driven wheel as an anchor point and be easier to control but more likely to get stuck.The speed limiter will be out 25% so top speed will drop.No need to reset the gears if you go with a true-track or similar gear driven style LS
The 4:10s on factory 29s make for a fun truck.You need a speedo gear for 98s and older to get back to stock
cheers