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Topic Review (Newest First)
04-17-2012 05:30 AM
mynewjeep Jeep - Build My Own - Vehicle Summary

I did not choose the 4.10 . All I did was choose the 5 Speed Automatic. The 4.10 was standard. I also did not choose the Max Tow Package.
04-16-2012 09:36 PM
mynewjeep I think they ordered it wrong ! Go on the Jeep site and build a Rubicon.
04-16-2012 11:47 AM
Comac90
Quote:
Originally Posted by jeepkingtn View Post
BuildHis date or 9-09-11 9:02am
I'm officially stumped ... Maybe they had a pricing change????

T
04-16-2012 12:05 AM
mynewjeep Sorry. When I mentioned that my JKU has a 3.73 with the Max Tow Package, I forgot to mention that I do not have a Rubicon. I have a Sport.
I you go on the Jeep site and build a Rubicon, I seems as though the 4.10 is standard, even it you don't choose the Max Tow Package. I believe that you have to actually choose the 3.73 option to get it.
04-13-2012 07:22 PM
mynewjeep Got my build plan and it has:

> DMEP 3.73 Rear Axle Ratio

My jeep has an Automatic Transmission with Max Tow Package . I believe that if you have the Automatic transmission on the JKU with the Max Tow Package, it automatically upgrates the Rear Axle Ratio to 3.73 .
04-12-2012 06:40 AM
jeepkingtn Sorry for the double post!
04-12-2012 06:15 AM
jeepkingtn Build date is 9-09-11 9:02am. The mileage rating is also lower with 4.10 gearing.
04-12-2012 06:10 AM
jeepkingtn BuildHis date or 9-09-11 9:02am
04-12-2012 05:41 AM
Comac90
Quote:
Originally Posted by jeepkingtn View Post
My window sticker says the same thing.
Out of curiosity, whats the build date? I'm thinking you have one of the first ones built since the very first 2012 rubicons with autos built DID have 4.10s at no charge. Whats gonna be odd is if its not July/2011.

T
04-11-2012 08:35 PM
jeepkingtn My window sticker says the same thing.
04-11-2012 03:02 PM
Matador
Quote:
Originally Posted by alang_z33 View Post
Be sure your not seeing the "4:1 Rock-Trac Part-Time 4WD System" listed in the standard equipment section and confusing that with 4.10 gears. This is referring to the transfer case ratio.

Your window sticker should explicitly say "4.10 Rear Axle Ratio" under optional equipment. I had to look around for a while to find an auto with this.

Exactly.
Here is a copy of my window sticker

04-11-2012 03:01 PM
12JKUR My 12 rubi came w/4.10s at no charge. Not sure ive seem a rubi w/out. My sticker shows 4.10s.

If you don't mind 15mpg, they are the way to go, if not, order one w/3.73's
04-11-2012 03:00 PM
-JC- I'm not sure if this relates to what is being said, but I have a '12 Rubi JK with 4.10, manual tranny. 1st gear is almost unuseable on flat ground. IT essentially just gets the jeep moving, at 10mph I'm at 3000rpm. On flat ground, I usually start in 2nd. More than enough power.
04-11-2012 02:56 PM
bkap305 My 6 speed standard Rubi came with 4:10 and I wouldn't have it any other way. It is quick off the line, shifts at a comfortable rpm, and gets between 18 and 21 mpg. It is a 2012.
04-11-2012 02:44 PM
Comac90
Quote:
Originally Posted by Thracks View Post
This is false. Taller gears puts a higher load on your engine because it has a less usable range with the gears being further apart. Low gears allow your engine to work less while producing more wheel torque since the power is multiplied that much more.
I don't totally follow you on the 'less usable range with the gears being further apart comment.' ... what do you mean? What gears? Diff gears between 2 different rigs? Drive ratios between each gear in the tranny?

It sounds like you're saying that at a given RPM, 3.73s put higher stresses on the engine than 4.10s because the engine is operating outside of it's optimal RPM range. By that logic, 5.88s would put a lot less wear and tear on an engine than 3.21s ... which doesn't make sense to me.

Do you have some references or something to back that up?
04-11-2012 01:28 PM
alang_z33 Be sure your not seeing the "4:1 Rock-Trac Part-Time 4WD System" listed in the standard equipment section and confusing that with 4.10 gears. This is referring to the transfer case ratio.

Your window sticker should explicitly say "4.10 Rear Axle Ratio" under optional equipment. I had to look around for a while to find an auto with this.
04-10-2012 11:43 PM
Thracks
Quote:
Originally Posted by JohnT11 View Post
Another way to look at a numerically lower ratio is that it's less wear and tear on your engine since you'll be at lower RPMs.
This is false. Taller gears puts a higher load on your engine because it has a less usable range with the gears being further apart. Low gears allow your engine to work less while producing more wheel torque since the power is multiplied that much more.
04-10-2012 10:28 PM
Comac90
Quote:
Originally Posted by jeepkingtn View Post
I have 4.10's on my 2012 JKUR Automatic. Didn't cost extra, are great off-road too!
You may want to double check your window sticker. Assuming there has not been some mid-year pricing change that I'm unaware of, if 4.10s are not specifically listed under optional equipment as "4.10 Rear Axle Ratio" for a $50 charge, then I would question whether you actually have 4.10s.

The only exception that I know to this is on the Rubicons (autos AND manuals) that hit D1 status prior to or around 7/6/2011 ... all Rubicons that hit D1 prior to ~7/6/2011 had 4.10s. On those first few, I have no idea what the window sticker said .... anyone??? UpHillBill may chime in and be able to shed some more light - he had to go through quite a bit of work, as I recall, to get his changed from the then standard 4.10s to 3.73s.

Bottom line as has been said: for Rubicons, 4.10s are standard on the manual, 3.73s are standard on the auto and 4.10s are optional on the Rubicon auto for a $50 charge (again, assuming there hasn't been some mid-year pricing change I'm unaware of).

T
04-10-2012 08:29 PM
jeepkingtn I have 4.10's on my 2012 JKUR Automatic. Didn't cost extra, are great off-road too!
04-10-2012 08:11 PM
subunix
Quote:
Originally Posted by MrMagoo View Post
Very misleading window sticker. I think it would it be a reasonable conclusion to think you were getting the 4.10 if that were the only ratio listed. I wonder how many potential owners will be mislead to thinking they're getting the 4.10s with the automatic.
AGREED! Im currently dealing with this on my '12 Rubicon, I was told by the dealer that I had 4.10's, didn't find out until i got my build sheet that i actually have 3.73's (didn't know to check that first, first jeep) called them today (dealership) and they still swear I'm supposed to have 4.10's , something to do with me having the max tow package... ill post an update when i hear back... incredibly frustrating... anyone know if there are seperate part numbers on the rear axle for 3.73 vs 4.10? i snapped a pic of my rear axle part number if anyone has any info
09-26-2011 11:53 AM
panthermark
Quote:
Originally Posted by MrMagoo View Post
Very misleading window sticker. I think it would it be a reasonable conclusion to think you were getting the 4.10 if that were the only ratio listed. I wonder how many potential owners will be mislead to thinking they're getting the 4.10s with the automatic.
I agree...
That is very poor communication on Jeeps part. If I walk up and look at the window sticker...and is says 4.10's standard.....with the automatic tranny marked as optional....I would assume it has 4.10's. I know buyers need to do their homework....but a buyer should not have to go through the history of the JK to figure out which models years and options were offered as what....just to find out if the a Rubi has 4.10's or 3.73's.
09-26-2011 11:14 AM
JohnT11 I got the 3.21s (against my will), and I'm not disappointed in the least. Does it have the pickup of my old 400 V8 GTO? No. But when you stomp on the gas, it takes off, so I'm good.

Another way to look at a numerically lower ratio is that it's less wear and tear on your engine since you'll be at lower RPMs. It probably won't be noticeable, but you never know.
09-26-2011 12:39 AM
MrMagoo Very misleading window sticker. I think it would it be a reasonable conclusion to think you were getting the 4.10 if that were the only ratio listed. I wonder how many potential owners will be mislead to thinking they're getting the 4.10s with the automatic.
08-30-2011 07:35 PM
panthermark ^^^Agreed with both of the above. It is one of the reasons why I keep going back and forth between 3.21's and 3.73's since this will be my daily driver (with a lot of highway miles) with very light off-roading since I'm looking at an auto. I think the 3.73's might be a tad low for my particular use (strictly because of highway travel)....but they are very good option for most Wrangler's out there.
08-30-2011 06:47 PM
Up Hill Bill ^^^ Comac90 pretty much hit it square on the head. I'm not going to lift and will go no larger than 33" tires. The 2012 auto with 3.73s is geared plenty low! Very peppy, Loves climbing hills! Perfect match with stock tire size.

If your going to go to 35" tires, get 4.10s. If your going to tow max loads on steep grades at altitude, get the 4.10s. If your building a dedicated rock crawler with big tires, 4.10s might not be low enough.
08-30-2011 06:35 PM
Comac90
Quote:
Originally Posted by penberth View Post
I am looking at a Rubi with Auto Tranny.

This is what I thought, but just wanted to confirm it. I will also ask for a build sheet.

I guess I need to figure out if the 3.73s would be fine, or if I hold out for the 4.10s.
There are a couple of recent threads on this ...

The quick answer is do 4.10s and be done with it.

Most, will want 4.10s because it's peppier off the line. For 'me' (and I'm in the minority), 4.10s with the auto, 4 to 1 T-case, and stock 32" tires is geared too low in my opinion. 1st gear, low range can be un-usable in low traction situations ... and I'm willing to sacrifice on-road peppy-ness for off-road ability, so if I was staying stock, I'd do 3.73s. .... or better yet, just get the manual with 4.10s - then your problem is solved.

That said, I didn't stay stock ... with the new auto, 3.73s and the stock 32" tires, final drive calculates out to nearly the exact same as 4.10s with 35" tires.

point: if you're increasing tire size at any time in the future, opt for the 4.10s.
08-30-2011 03:51 PM
JohnT11
Quote:
Originally Posted by penberth View Post
I am looking at a Rubi with Auto Tranny.

This is what I thought, but just wanted to confirm it. I will also ask for a build sheet.

I guess I need to figure out if the 3.73s would be fine, or if I hold out for the 4.10s.

Depends on what you want to do with the Jeep. If you're just going to drive it around on the street, I doubt you'd be unhappy with 3.73s. If you're going off-road, hold out for the 4.10s.
08-30-2011 12:07 PM
penberth
Quote:
Originally Posted by panthermark View Post
^Yup....I think that is it.
4.10's are standard when you set the standard manual Rubi.
3.73's are standard when you get the optional auto Rubi.
I am looking at a Rubi with Auto Tranny.

This is what I thought, but just wanted to confirm it. I will also ask for a build sheet.

I guess I need to figure out if the 3.73s would be fine, or if I hold out for the 4.10s.
08-30-2011 12:00 PM
Comac90
Quote:
Originally Posted by panthermark View Post
^Yup....I think that is it.
4.10's are standard when you set the standard manual Rubi.
3.73's are standard when you get the optional auto Rubi.
Correct ...

That said ... Didn't all (manual and auto) Rubicons that hit D1 before 7/6/11 get 4.10s as standard (unless you had them changed like UpHillBill)?

T
08-30-2011 11:56 AM
panthermark
Quote:
Originally Posted by Lighting Guy View Post
I could be wrong, but I think the 4.10's are listed as standard, because they ARE standard with a manual... which is also standard. It is when you change the tranny to auto, that it brings the gears down to 3.73, unless you add it separately for $50. (and maybe with a tow package, that part I can't confirm, dunno if anyone can, haha.)
^Yup....I think that is it.
4.10's are standard when you set the standard manual Rubi.
3.73's are standard when you get the optional auto Rubi.
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