Supercharged 3:73 vs 4:10 vs 4:56

Hey guys. I have a 2005 dclb with a Magnuson s/c and stock gears with 33’s. Exhaust and headers, and the 2.85 pulley and tuned by @JustDSM. Just wondering who has went with a similar setup from stock gears to 4:10s or 4:56 and how did you like it? So far I like how I have a good amount of power through all gears and at high rpms. Also I don’t tow anything. I’m kind of just wondering how big of a difference it is to go to 4:10s. I would like a little more power and speed but maybe a smaller pulley and doing more mods is the way to go. How much speed do you lose with the 4:10s and 4:56s? Is the torque gains worth sacrificing the top speed?

 

Subbed. I'm working on a 4.10 swap, I've picked up a 4.10 front diff from a 4cyl truck at a salvage yard. but ECGS is building the rear carrier for me and they have a 6-8 week lead time. Right now its just a waiting game.

 

Currently runnin the S/C, 305/70r16s, front n rear steel bumpers, shell. Will at ECGS is setting me up with 4.88’s. Primarily due to weight. Log jam ahead of me so waiting until early August for gears to land.
Contact Will and tell him your situation

 

My truck is still together with the stock 3.73 gears. So I’m ok with the wait.

 

Are you a manual or an auto? Keep in mind over-gearing will give you great torque and a good crawl ratio, but will detract from acceleration and lead to high cruising RPMs. Top speed is a non-factor, the trucks are electronically limited (unless bypassed) and even then a lifted truck on oversized tires has no business at 110+ mph. I'd suggest 4.10s at most with 33s if looking for acceleration with the SC. I recommended the same to @White lightning boosted who made the swap on his truck, he could give you first hand insight.

 

@crashnburn80 made a suggestion according to my needs and was spot on. 4:10's and 33's are aces for highway use but offroad awesome. never a day i wished different.

 

crawler? id consider 4:56's if youre heavily weighted and its not a freeway frequent. mine is more of a methanol consuming freeway banshee. i like my 4:10's.

 

I'm SC on 35's with light armor running 4.56 auto V6 and this truck screams. I would go with 4.56 on your 33's if you're weighed down that way if you decide to go 35's in the future you wont need to mess with gearing. Highway turning 2250 rpms @ 70mph and absolutely no gear hunting on cruise control even on inclines.

 

Auto transmission with valve body mod. I'm not crawling or weighed down. Lots of highway and city driving. Its my daily. I just want to accelerate faster. Sounds like 4.56 would be good. I'm going to see what RPM's I'm pushing with the stock gears. I do kind of want to go up to 35's.

 

Decide on your tire size before your gears. If going to 35s 4.56 would be good. If staying on 33s, 4.56 will likely mean you rev a lot quicker, but those revs don’t translate to acceleration as effectively as 4.10, something to keep in mind. I’ve overgeared a truck before, awesome on the trail, lots of torque on the street but not as much acceleration. If you are only running a 2.85 pulley, you also have plenty of room to add more power for far cheaper than gearing. Swap to the pulleyboys quick change pulley, step down to a 2.7 or 2.6 pulley, add an enclosed cold air intake and swap to a higher output fuel pump. The power is noticeably improved and the CAI allows power to redline whereas the stock air box definitely maxes out in the mid-upper RPMs and the power falls flat.

 

I have the fuel pump already and the URD cold air intake. Why do you recommend enclosed cold air intake? Would it be better than the URD one?

 

this couldnt be written better. tire size, truck duty, and weight i believe are the considerations. or just boost the truck and add nitrous. joking....kinda. if i was armored id go 430's. 456's if it rarely saw highway. keep in mind my 410's from 373's make great freeway passing power but mileage reflects too. i just refuse to check my mpg's so i can sleep at night.

 

urd intake is great. but at times the sensor wanted to spaz out. ultimately you want the coolest, cleanest air delivery. the ecu will thank you.

 

Also consider your elevation and local highway speed limit. I drive montana highways at 5-7k feet above sea level. On 33s I won’t go over the 80MPH speed limit but kept stock gears since I didn’t want high RPMs while cruising the highway. Maybe someone local to you can give you a ride on their regeared truck. Good luck Op.

 

this is a valid point. i almost never exceed 70mph. but i love how fast i achieve it. 33's @60 is 2k rpm for me.

 

My average is like 14-15 right now on the 3:73s...not terrible. I’ve been justifying it by really taking advantage of fuel points.

 

yea I’m trying to get to 70 a little faster lol

 

smaller pulley, lower gears, and harder right leg exercise. im actually very happy with my setup. i never floor my truck. its that responsive.
https://youtu.be/XJzLTxVal6A these are e-load tires too with tool payload. 85mph as i enter freeway

 

Also if you want to accelerate faster, watch your wheel and tire weight. Running C-loads instead of heavy E-load and selecting lighter wheels will allow you to accelerate faster and get better MPG.

 

@Biscuits in the zone. happy 4th stranger.