Swapping up to the 4.10s

[Rusty PW]

Didn't think you could get 4.10s factory in a JT, I think they are all 3.73, even with max tow. (with a diesel)

All diesel JT's are 3.73.

Sponsored

 

[UTDieselRubi]

I hadn't had a problem staying in 8th with my Nitto Trail Grappler 35x12.5x17 on the 3.73 ( debated to 3.55 by the tire size ).

Going to the 4.10s only puts me at a .08 deficit from oem based on the simple math method of percentage of tire difference x 3.73.

It's completely situational , if I lived out West or was operating heavy due to a trailer or rtt & gear , I would have moved up to 4.56.

I only pull my boat trailer to my mechanic for service and he meets me at the ramp with his 1 ton every 100 hours.

Coolers loaded with ice and deer stands aren't enough weight to make me go to any higher ratio than what is closest to oem rpm range.

I have closed the chapter of life where I needed a full size tow rig for the boats and travel trailers I've had.

That towing was done with 3/4 & 1 ton crew cab diesels and I flat towed my 85 4Runner on 36s to hunt out of.

Fair. From the sounds of it, my internal debate is slowly leaning to 4.56s, in my situation, that is probably the best route. I load mine up enough and tow moderately, plus these damn mountains here ensure lower gears, pretty to look at and be in though. The real problem with going to 4.56s is then I'll have the voice in my head come back telling me I need 39s.....

 

[CrazyCooter]

Didn't think you could get 4.10s factory in a JT, I think they are all 3.73, even with max tow. (with a diesel)

That was my snarky point!

All these comments about gas rigs, manuals, and other platforms while the original question was whether to swap from the OE 3.73's to 4.10's in a diesel JT, yes?

 

[RudeJeepin]

Didn't think you could get 4.10s factory in a JT, I think they are all 3.73, even with max tow. (with a diesel)

As stated, 3.73 with all Jeep EcoDiesels, regardless of trim, Wrangler or Gladiator.
Also, there is no "max tow" diesel.

 

[UTDieselRubi]

That was my snarky point!

All these comments about gas rigs, manuals, and other platforms while the original question was whether to swap from the OE 3.73's to 4.10's in a diesel JT, yes?

Ah I gotcha, I misread that lol. Yes indeed your point was valid then.

 

[CrazyCooter]

For the record (as posted in the 100's of other threads that are just a search away), my preference is 3.73's up to 37's unless you tow heavy all the time in steep country and then 4.10's. Even then I felt 4.10's and 37's was a bit too deep. I did 4.10's and 38's to balance to difference.

 

['22JTRD]

For the record (as posted in the 100's of other threads that are just a search away), my preference is 3.73's up to 37's unless you tow heavy all the time in steep country and then 4.10's. Even then I felt 4.10's and 37's was a bit too deep. I did 4.10's and 38's to balance to difference.

And maybe now after 6 pages of this, would you think about letting me know what you think about having the 4.10s and 38s ?

 

[CrazyCooter]

And maybe now after 6 pages of this, would you think about letting me know what you think about having the 4.10s and 38s ?

Had you done a search prior to posing you will find many threads where I have expressed my thoughts at length.

I'm tired of answering the same questions for people who are too lazy to look for he info. I was one the first to make the swap as an early ecodiesel owner and a gear shop owner.......I have also towed some of the heaviest loads over the steepest terrain on the west coast.

Sometimes it's just more fun to troll the internet experts?

 

[RudeJeepin]

My only question is, why no 4.27?

 

['22JTRD]

Had you done a search prior to posing you will find many threads where I have expressed my thoughts at length.

I'm tired of answering the same questions for people who are too lazy to look for he info. I was one the first to make the swap as an early ecodiesel owner and a gear shop owner.......I have also towed some of the heaviest loads over the steepest terrain on the west coast.

Sometimes it's just more fun to troll the internet experts?

I guess you may really be crazy...

My OP wasn't asking any questions or looking for advice.

Maybe you should read it again.

I just posted that I had ordered 4.10s and why I decided to.

Really didn't expect so many folks to try and convince me I didn't do it like they would.

I did my homework before ordering and didn't come here asking for advice.

If anything maybe I thought someone on here may have done the same thing and chime in with a report.

Very similar to other posts that I have replied to a member looking for info.

I guess you decided it's classified Intel since nothing popped up you had posted that I found.

Based on you having already done the same setup and not chiming in telling me not to do it, I will just assume you are happy with it.

Sorry to bother you , Troll On

 

[JTdiRtyD]

I just posted that I had ordered 4.10s and why I decided to.

Really didn't expect so many folks to try and convince me I didn't do it like they would.

Gotta love forums!

Funny thing is, I don't find the gladi forums that bad in this regard, at least not compared to others. The Tacoma forums are really bad for this, but it's usually "why would you ever do that and void your warranty?! The factory stuff works just fine!" That and gas filler cap holders... wanna see a tacoma owner lose their shit? Tell them the truck needs a gas cap holder...

 

['22JTRD]

FYI, for the 4.10 / 38's on the EcoDiesel Naysayers...

My convo with Ryan at Exxodus

Hey Dale,

Since you are in Florida , I think you should be fine with the 4.10. Where we live out here , I would typically recommend 4.56.

Choose your vehicle:: Jeep Gladiator
What model and year?: 2022 JTRD
What can we help you with?: Mopar 2" Bilstein Lift
Teraflex 1.5" Leveling Kit
Teraflex 2" Front Shock Mount Extension
Teraflex 1.5" Carrier Bearing Drop Kit
Clayton Adjustable Front Trackbar
Clayton Adjustable Bent Rear Trackbar
37.75" measured spare fits under bed
Nitto Ridge Grappler 38x11.50r17
( They measured 37" on the ground )
Rugged Ridge Arcus Front Bumper
Badland Apex 12k Winch
LOD Destroyer Frame Mount Sliders

Originally from Mesquite, Texas
Live in Flat Earth Florida now
I don't tow or plan to add extra weight of Overland gear or RTT

Looking to see if you have done a swap from the oem 3.73 to the Spicer 4.10 ratio and if so what was your opinion

Doing the simple math using oem tire at 33" , New 37" and 3.73.

That drops the 3.73 to an effective 3.33 with a new ratio of 4.18 needed to return the to oem.

Several online Calculators and charts point to the 4.10 giving a slightly under gear ratio.

The next size being 4.56 gives it a higher amount of over gear.

Being that I have no plans on anything other than getting up out of the water and mud while hunting here and maybe a bucket list trip out West with moderate offroad use do you feel that the 4.10 will be adequate ?

Thanks for your experienced information.

If I was still in Texas I would definitely be dropping it off to you for the work and tubing The Guadalupe again.

 

[Advntrbound]

Pulled the trigger today and ordered the Spicer 4.10s from the gasser and Master Install kits.

Don't want to lose the top end highway mpgs that would come from upping to the 4.56s.

Since adding the Mopar 2" lift and going up to Nitto Ridge Grappler 38x11.50r17 last Saturday, I have felt the need to bring the power band back closer to oem spec.

The actual 37" tire on the truck dropped the ratio to 3.3 and effected what I feel is unacceptable fuel consumption at launch from stop.

I ran Nitto Trail Grappler 35x12.5x17 for the last 3 years and felt the 3.73 ( 3.55 due to 35" tire size ) was adequate since I don't tow and live in Flat Earth Florida

Tire Size Gear Calculator sez 4.22 to get back to oem spec, so it will end up being. 12 underdriven with 4.10s.

That small amount of underdrive should be acceptable at launch and give a fraction better highway mpgs.

Dale, keep us posted on what you think about the 4:10s. I have a gasser with a MT and 35s. I never use 6th gear and rarely hit 5th. Now that we have a camper and live in the Ozarks, I'm affraid some of the hills will have me climbing them in 2nd or 3rd at a turtle's pace. SO a re-gear will most likely be in the future.

 

[Blade1668]

4.10 if you don't tow & 4.56 if you're heavy is how I see it sorted out.

4.10 a fraction better mpgs at Highway speeds and suitable for everything else.

4.56 a fraction worse at highway speeds and a fraction more grunt under load.

Pick your poison, we're still driving bricks

As a apples compared to watermelons or carrots. I can understand your selection. As no skin in this the chart is a guide. Years ago with my XJ used it as a guide too. Factory tire size of 215-225 tires and 3:55 I re-geared to 4:56 and 33-35 tires with gasser 4.0 I actually got better performance and mpgs with 4:56 gears with lockers. In no way do I disagree with your choice. It makes sense to me especially with a diesel and a double overdrive transmission that our gladiators have. You know what you need and want and it makes sense. I was going for performance and lower gearing and got better mileage as a bonus even towing. My 05 Wrangler Unlimited with 3:73 gears and the same 33 is a dog running that same set of tires in some ways "heavy ass MT tires" that would likely feel like stock with 4:10's and lighter weight 33's.
I think some don't know or understand the overdrive and slippage of auto transmissions plus likely different valving and shift points.

 

[VA6489]

And maybe now after 6 pages of this, would you think about letting me know what you think about having the 4.10s and 38s ?

interesting reading. I am running BFG 39s on my 2021JTRD. From a drivability stand point it spent a lot of time down shifting at every little hill. Lower RPMs did help out with fuel mileage over the 3.73. I do not live in a Flat state and do wheel my rig. After much discussion and research ( Currie, East Coast Gear) I now have 4.56 gears. Yes it runs a bit higher in RPM but I do not spend a lot of time running over 70 MPH.
I find it easier to drive, the motor doesn't seem to work as hard to launch and maintain. Roll on passes do not require a down shift and easily launch you to 75-80MPH if not careful. I do tow a small trailer so deeper gears are a benefit there too. I realize this is not a 6 Liter Diesel making 1000#ft of torque so my expectations are tempered understanding I have 1/2 the torque to get stuff done.
My test track is a 121 mile round trip to work in a mix of driving conditions from 65MPH to stop and go. For this run over 5 days I average 21MPG. Without the rack and topper I was seeing 24-25 mpg with the occasional 27 on a good day. Rpm range is 1400-1700, shifts at 1900-2100.
Notes:
- Flat fenders up front
- BFG 39 inch MT
- Softtopper cap
- Destin exo rack

The JT is a streamlined hay barn not made for Hi-mileage. If you are never running outside of Flat Florida 4.10 would be a good choice. If you tow or head for the hills 4.56 would be a better choice.

Cheers

Sponsored