Gear upgraded, 3.08 to 4.10

[EnzoColorado]

I just upgraded the gear in my Suburban from 3.08 to 4.10! Still need to go to a speedo shop to get the speedometer calibrated. First drive today, it's feels quite a bit more responsive though it's funny to see 95 mph on the speedo while still on the freeway entrance ramp. Can't wait until next camping trip in September to New Mexico to see how much better it tows.

[TurnThePage]

I took my old F150 4.6L from 3.55 to 4.10. It made a HUGE difference. Unloaded highway mileage took a 1 mpg hit, but city driving and towing both had improved mileage. Not only that, I could suddenly maintain speeds towing in the mountains, and not have to worry about the truck grinding to a halt on long, steep climbs, which nearly did happen previously. It could suddenly cruise on the highway without dropping out of overdrive because a slight headwind or incline. The truck was so much more enjoyable to drive too. In short, it's the best mod I ever did to that truck, and I did a lot of them.

[BenK]

Gearing is only one component of getting torque to pavement...

Another, but NOT limited to, is the ICE and it's architecture

Then the two main computers controlling the ICE and automatic...of course their software n any tune(s) that might be there

Finally the driver...

That has too many components and software now takes much of the decisions away from the driver...but...often, too often, folks come here asking HOW2 override the algorithm (s)...

Since most of today's automatics are close ratio with double OD...many say don't need higher numeric diff ratios...ok for most, but those close to...at...or over their OEM spec...a higher numeric diff ratio benefits them...if they understand...

Most common ask is TOW/HAUL...should I use it...should I turn it off...and the common advice/recommendation/etc is to turn it off for better MPG...

Pretty soon the OEMs will take that option to turn it off away...betcha after one too many warranty claims...which will increase the cost/price cuz they will put in a strain gauge on the receiver...and then highly integrate that into even more computer controls...plus they will now know how much tongue weight vs trail model that will tell...tell lots n lots...

[Dave_H_M]

Yaaa, I did take physics courses and by golly got an A in one. We did all the lever calc stuff.

Now getting down to my approach rather than theory, can someone come up with any results with empirical data from road testing that would shoot holes in my thoughts.

Rubber on the road.

[dodge_guy]

larry barnhart wrote:
two brothers stopping at the alpenlite factory on their trip south. Both had the same fifths and trucks but one had the 4.10 and one had the 3.73.
The 4.10 always used 5 more gallons of gas at every fill up.

chevman

Yes, but it hauled the same load easier. I'll take 5 extra gallons over struggling to stay in a gear.

[larry_barnhart]

two brothers stopping at the alpenlite factory on their trip south. Both had the same fifths and trucks but one had the 4.10 and one had the 3.73.
The 4.10 always used 5 more gallons of gas at every fill up.

chevman

[BenK]

Agree...kinda sorta gave up trying to help folks understand that there is no difference between a longer lever arm (longer 2x4 on the same fulcrum) on a higher numeric gear set.

Add that too many just look at one component of the gear box system between the ICE and pavement. Most just look at the tranny (gearbox) gear ratios, or just the diff ratios (another gear box)...

What matters are the final gear ratio from ICE to pavement and the ICE's torque/HP curve (in rev's) in reference to that final gear ratio at pavement...

[dodge_guy]

Dave H M wrote:
I agree with the RFC man.

I have 4.30's in my 2012 F250. I listened to all the hype about gearing down for towing.

If I had it to do over again, i would be running the 3.73 and dropping down to 5th when towing.

I personally think that those tow ratings are set up for the folks that just drop it in D and leave it there. It helps the manufacturer out some with warranty issues and psycho issues with the drivers that run all the time in D.

I'm guessing some people don't understand physics. A longer lever makes things easier to lift. Same goes for lower gear ratio. I run mine in D and shift it when and if necessary. It's all about making things easier not harder.

[dodge_guy]

EnzoColorado wrote:

kw/00 wrote:

dodge guy wrote:
Since you need to get the speedo addressed, why not get a custom tune from Black Bear? That will really wake up that 5.3 especially with how well it will change the shift strategy!

Bingo! Could not have said it better myself. I have the EFI Live tune and love it. The tune is worth the time and investment to look into it.

Okay now I'm curious. Other than shift strategy, what else does a Blackbear tune do? I don't want to use higher octane fuel. Right now I use 85 here in Colorado.

You can specify any octane you want. You will only gain approx 10-15 HP same for TQ. Nothing to write home about but it does help. And the new shift strategy will be night and day better.

[EnzoColorado]

Dave H M wrote:
I agree with the RFC man.

I have 4.30's in my 2012 F250. I listened to all the hype about gearing down for towing.

If I had it to do over again, i would be running the 3.73 and dropping down to 5th when towing.

I personally think that those tow ratings are set up for the folks that just drop it in D and leave it there. It helps the manufacturer out some with warranty issues and psycho issues with the drivers that run all the time in D.

The 3.08 worked fine for me on rolling hills and even lower elevation mountain passes. It's the higher passes that give me issues. People are correct to point out some of overall ratios between 3.08 and 4.1 with my 6 speed overlap. The new 4th gear ratio is essentially the same as the old 3rd gear's. However the new 3rd gear's over ratio is 6.29, vs. the old 2nd gear's 7.27.

Gear Gear ratio Overall Ratio
3.08:
*************************
1 4.03 12.4124
2 2.36 7.2688
3 1.53 4.7124
4 1.15 3.542

4.10:
************************
1 4.03 16.5633
2 2.36 9.6996
3 1.53 6.2883
4 1.15 4.7265

So the new 3rd gear split the huge gap between the old 2nd and old 3rd nicely. I can use the 3rd to climb passes like Monarch pass now at 50 mph with nice breeze to cool the engines/tranny, and going down, the new 2nd gear will hold speed far better than the old 2nd gear (which I had to use the brake every 2 to 3 curves). Sure either gear still has me below my max tow rating but the new one should be far easier to drive.

[EnzoColorado]

kw/00 wrote:

dodge guy wrote:
Since you need to get the speedo addressed, why not get a custom tune from Black Bear? That will really wake up that 5.3 especially with how well it will change the shift strategy!

Bingo! Could not have said it better myself. I have the EFI Live tune and love it. The tune is worth the time and investment to look into it.

Okay now I'm curious. Other than shift strategy, what else does a Blackbear tune do? I don't want to use higher octane fuel. Right now I use 85 here in Colorado.

[EnzoColorado]

AJBert wrote:
No real need to go to the "speedo shop". A very basic tuner will allow you to change the gears for probably less than a shop will charge you and take less than ten minutes.

BTW, you will LOVE the difference while towing! However, expect you daily driving mileage to drop considerably.

I just called a local shop that does speedo recalibration. They told me they only do the old mechanical style speedo. So I guess I'm on my own for this.

I looked online last night for tuners and seem like the cheapest are over $200. What's a "basic tuner" cost? I may have looked at high end ones. Really have no knowledge about tuners.

[EnzoColorado]

GordonThree wrote:
Nice! How hard was it to find a shop to do the work?

Don't forget to update your signature 🙂

I called a couple of the local 4x4 shops and got quotes between 1800 to 3300. I end up going with the 1800 since they seem to know what they are talking about regarding the carrier and locker issue and they have good reviews. Took them a day and so far the burb drives great.

[Dave_H_M]

I agree with the RFC man.

I have 4.30's in my 2012 F250. I listened to all the hype about gearing down for towing.

If I had it to do over again, i would be running the 3.73 and dropping down to 5th when towing.

I personally think that those tow ratings are set up for the folks that just drop it in D and leave it there. It helps the manufacturer out some with warranty issues and psycho issues with the drivers that run all the time in D.

[Huntindog]

dodge guy wrote:

RCMAN46 wrote:

dodge guy wrote:

RCMAN46 wrote:
After first gear you may not find much difference.

The 4.1 gives nearly the same gear ratios as going down one gear with the 3.08 after first gear and you lose the overdrive.



3.08 4.1 Equlivant

2.97 3.95 1st
2.31 3.08 2nd
1.57 2.09 3rd
1.18 1.57 4th
1 1.33 5th
0.75 1.00 6th

Note how close the gear ratios above first gear are.

Not even close! Each ratio becomes more efficient at towing a heavier load. Dropping a gear does nothing!

You do not see the same numbers that I do.

6 th gear with 4.1 is the exact same ratio as 5 th gear with 3.08.

4 th gear with 4.1 is also exact same ratio as 3 rd gear with the 3.08.

The others are very close except of course 1 st gear which is almost never used beyond 5 mph.

The 6 speed auto with a torque converter has more than enough torque in first gear regardless the axle ratio.

I know what you are saying, but going with a lower ratio ring and pinion you effectively make each gear more efficient! It changes the overall ratio of each gear. What you are saying is the same as starting out in 2nd gear instead of using first.

There is a reason that tow ratings most always increase with a lower rear axle gear ratio.

Despite what some think... It matters. Many auto engineers that set the ratings agree.

Maybe the internet experts know better,:B

[dodge_guy]

RCMAN46 wrote:

dodge guy wrote:

RCMAN46 wrote:
After first gear you may not find much difference.

The 4.1 gives nearly the same gear ratios as going down one gear with the 3.08 after first gear and you lose the overdrive.



3.08 4.1 Equlivant

2.97 3.95 1st
2.31 3.08 2nd
1.57 2.09 3rd
1.18 1.57 4th
1 1.33 5th
0.75 1.00 6th

Note how close the gear ratios above first gear are.

Not even close! Each ratio becomes more efficient at towing a heavier load. Dropping a gear does nothing!

You do not see the same numbers that I do.

6 th gear with 4.1 is the exact same ratio as 5 th gear with 3.08.

4 th gear with 4.1 is also exact same ratio as 3 rd gear with the 3.08.

The others are very close except of course 1 st gear which is almost never used beyond 5 mph.

The 6 speed auto with a torque converter has more than enough torque in first gear regardless the axle ratio.

I know what you are saying, but going with a lower ratio ring and pinion you effectively make each gear more efficient! It changes the overall ratio of each gear. What you are saying is the same as starting out in 2nd gear instead of using first.