4.8l With A 4.10 Gear Ratio

jeremymike2 · December 17, 2010

I have recently just purchased a 4.10 gear for my 2007 GMC sierra 4.8L truck. For now until the gear gets here, i have a 3.23(which doesnt make any sense why they would put that gear in there) but I was wanting to know what could i expect from this upgrade? I have aftermarket 20 inch wheels, done some engine mods and had the truck tuned. Any feedback would be appreciated, thank you.

jro909 · December 17, 2010

it will have alot more bottom end grunt...suck more gas on the highway...overall they are worth having on 4.8s with the 4 speed trans...i wish i would of gotten atleast 3.73s

December 17, 2010

I have recently just purchased a 4.10 gear for my 2007 GMC sierra 4.8L truck. For now until the gear gets here, i have a 3.23(which doesnt make any sense why they would put that gear in there) but I was wanting to know what could i expect from this upgrade? I have aftermarket 20 inch wheels, done some engine mods and had the truck tuned. Any feedback would be appreciated, thank you.

I'm curious to know this myself. Especially how it affects your RPM's at highway speeds. I am planning this same swap here soon...

I know that right now, with 3.42 gears, I can cruise 70mph @ 1950 RPM. That's awesome!

From the online calculator on Richmond Gears website ( http://www.richmondgear.com/101032.html ), the best I can tell a 4.10 gear will turn is about 2330 RPM @ 70mph with a 4L60E in overdrive.

Doug_Scott · December 17, 2010

I have recently just purchased a 4.10 gear for my 2007 GMC sierra 4.8L truck. For now until the gear gets here, i have a 3.23(which doesnt make any sense why they would put that gear in there) but I was wanting to know what could i expect from this upgrade? I have aftermarket 20 inch wheels, done some engine mods and had the truck tuned. Any feedback would be appreciated, thank you.

I'm curious to know this myself. Especially how it affects your RPM's at highway speeds. I am planning this same swap here soon...

I know that right now, with 3.42 gears, I can cruise 70mph @ 1950 RPM. That's awesome!

From the online calculator on Richmond Gears website ( http://www.richmondgear.com/101032.html ), the best I can tell a 4.10 gear will turn is about 2330 RPM @ 70mph with a 4L60E in overdrive.

The calculator is right. Mine is just under 2500 rpm at 120 km/h with the 245-17 tires. It is a bit lower when I have the 265-17 tires on. Huge difference from a dead stop compared to the 3.23. Fuel mileage averages about 16l/100km on mine in mostly city driving. I have seen 11l/100km (avg over a 200km highway trip) on the highway driving at 100km/h.

December 17, 2010

The calculator is right. Mine is just under 2500 rpm at 120 km/h (74.5 MPH) with the 245-17 tires. It is a bit lower when I have the 265-17 tires on. Huge difference from a dead stop compared to the 3.23. Fuel mileage averages about 16l/100km (14.7 MPG) on mine in mostly city driving. I have seen 11l/100km (21.38 MPG) (avg over a 200km (124.27 Miles) highway trip) on the highway driving at 100km/h (62.14MPH).

^^^^ Fixed it for ya ^^^^

Doug_Scott · December 17, 2010

The calculator is right. Mine is just under 2500 rpm at 120 km/h (74.5 MPH) with the 245-17 tires. It is a bit lower when I have the 265-17 tires on. Huge difference from a dead stop compared to the 3.23. Fuel mileage averages about 16l/100km (14.7 MPG) on mine in mostly city driving. I have seen 11l/100km (21.38 MPG) (avg over a 200km (124.27 Miles) highway trip) on the highway driving at 100km/h (62.14MPH).

^^^^ Fixed it for ya ^^^^

You still got it wrong for the mileage numbers. I am in Canada where we have the real gallon.... your mileage numbers are about 80% of what they should be.

December 17, 2010

You still got it wrong for the mileage numbers. I am in Canada where we have the real gallon.... your mileage numbers are about 80% of what they should be.

It's all greek to me...

rodram · December 17, 2010

With the 4.10 rear gears now, if you are towing anything, you will notice the difference in taking off from a dead stop and in the response when driving ... the 3.23 gears are put in there to be an economy light duty truck option ... but really not any suitable torque for handling larger tires or towing any loads ...

you will lose some fuel mileage at whatever your usual highway cruising speed is, but if you just slow down a little and keep the tach close to 2000 rpm then you can compensate for that ...

Arg · December 17, 2010

I had 4.10 rear in my 2008 Avalanche with the 6.0l. It would pull a house down. They are correct on the fuel. It would burn thru it. I know the 6.0l didn't help but I have since sold that and bought a 2011 Yukon XL Denali and it has the 6.2l AWD and it is better on gas than the avalanche. I pulled my deck boat(5000ib+) with that 4.10 rear end and you never knew it was back there the way it pulled off the line.

jdubya · December 17, 2010

I am curious to see your results on this upgrade. I am also wondering what it takes to perform this upgrade. Did you but the gears from GM or are they aftermarket?

Doug_Scott · December 17, 2010

I am curious to see your results on this upgrade. I am also wondering what it takes to perform this upgrade. Did you but the gears from GM or are they aftermarket?

I bought aftermarket gears, and one thing you need to know, the dealer cannot alter the ECM to account for the gear change on a 2010 for sure. Blackbear can do it though when you get the tune.

jeremymike2 · December 18, 2010

Im getting mine from Randy's ring and pinion. I got the 4.10 yukon ring and pinion because the cheaper ones would of created a gear whine. It wasnt to bad 303.00 for the ring and pinion and the installation kit. Not bad for having to save money. I really appreciate the feedback. Its going to be interesting, i'll comment when i get it tuesday.

desrtrat · December 18, 2010

with 275-55-20's with 410 gears and 4L65E trans i turn 2300 rpm at 70 mph..3.73 are about 250 rpm difference at 70. i myself would go 4.10

good luck

mkimber · December 25, 2010

I did this to mine 3 years ago. Best mod I've ever done period. My gas mileage stayed about the same except on long highway trips. Constant city driving mpg improved because it takes so much less effort to get it going off the line. City-hwy mix stayed the same. It runs about 2000rpm at 70 with 33" tires. It was around 1700 before if I remember right. I also put in a truetrac at the same time. The truetrac really I have a Wait4me tune already so I sent it back to get the speedo corrected.