Am I SOL?

[rubicon91]

3.73 are standard with autos, 4.10 with manuals, last time I checked. Auto Rubi? Yuck. I don't see the $800 4.10 option, under the options list. The auto trans option, might have overridden the 4.10 listed under standard equipment, and bumped you back to 3.73. Can't the trailer tow pack option, bump you back to 4.10's?

But like others have said, do what you're going to do, regear waaay beyond 4.10 if you feel the need to. If avoiding regearing at all cost, stick with 33" tires. I doubt you'd be happy with 4.10/35's in a Jeep.

If automatic trans, just set parking brake, put in drive to remove slop. Put a ziptie on driveshaft. Gas it to drive forward while someone watches the shaft.

Does your ECM have a gear setting like a Ford? Scan it and check what it says. But be aware, sometimes incorrect gear settings, and incorrect tires settings are purposely entered, to tune the speedo accurately.

I have 410s auto Rubicon with 35s. I never had any issues at all with my 410s and auto. And I came from a manual with 456s in it. I couldnt be happier. I do have some 488s sitting in the garage just in case I decide to go to 37s but that is a whole different story for another time. Also my upgraded 410 gears were only a $495 upgrade on the options for my 2017.

 

[rubicon91]

That's because the AT & MT are geared differently, which is why I suggested mounting what you want and see how it drives before fretting about regearing.

I've had this come up a few times over the years when Jeep folk were touting how much better their truck was than my Non-Jeep simply because theirs had "4.10 gearing". I don't know anything about it, but it sounds cool, so all off-road vehicles should have 4.10 gearing, right?

4.10 can work well on a Jeep, but what's important is how an engine and all of the gearing works together with the tyre circumference. 4.10 isn't a magic, universal ratio that works for everything, and it would be unsuitable for my truck. It may be perfect for yours, or another ratio may be better. Mount those 35s and see how it goes. You may find that the new tyre circumference, weight, and height of your Jeep makes it prefer a new ratio, but you'll be better off finding out what ratio you need once you get the rest figured out.

I agree here. Hell I know plenty who rock 35s with 321 gears in their Jeeps and dont mind it at all. I would see how it goes first and go from there.

 

[bdp1978]

Ive been running 35's on 3.73's all Summer without too much issue. Its not a racecar but its done fine. That being said I am going at least 4.88's this winter....possibly 5.38's.

The one thing I can ABSOLUTELY tell you is that if you really want 35's.....and you go with 33's you'll regret it everytime you look at the Jeep.

 

[Jurfie]

That's because the AT & MT are geared differently, which is why I suggested mounting what you want and see how it drives before fretting about regearing.

I've had this come up a few times over the years when Jeep folk were touting how much better their truck was than my Non-Jeep simply because theirs had "4.10 gearing". I don't know anything about it, but it sounds cool, so all off-road vehicles should have 4.10 gearing, right?

4.10 can work well on a Jeep, but what's important is how an engine and all of the gearing works together with the tyre circumference. 4.10 isn't a magic, universal ratio that works for everything, and it would be unsuitable for my truck. It may be perfect for yours, or another ratio may be better. Mount those 35s and see how it goes. You may find that the new tyre circumference, weight, and height of your Jeep makes it prefer a new ratio, but you'll be better off finding out what ratio you need once you get the rest figured out.

I appreciate the feedback; I do know that autos and manuals are different, and I did do my research (5 years ago) when I was Jeep shopping. I wanted the 4.10s based on staying in the green zone of this chart. With 35s, I'd now be in the yellow zone and this is a DD and mild trail rig in BC. As suggested, I'll just do it and see how it performs. My daily driving is near sea level so I'm sure it will be fine, but it might lug when I'm in the Rockies (I just got back from a cross-country trip to New Brunswick and plan to do it again next year).



Chart Credit: https://prodigyperformance.com/blog/jeep-wrangler-gear-ratio-calculator/

 

[Jurfie]

Auto Rubi? Yuck.

 

[Jurfie]

The one thing I can ABSOLUTELY tell you is that if you really want 35's.....and you go with 33's you'll regret it everytime you look at the Jeep.

You're right, of course. I'm just disappointed that I made a dumb mistake. Live and learn!

 

[(none)]

Man up, jack up one wheel and check it yourself by rotating it a few times.

All in all, it doesn't matter. 35s with 3.73s or 4.10s suck. I don't care what anyone claims. The only reason they claim otherwise is because they haven't driven with 4.88s.

 

[KenC]

use this site to find build sheet using VIN https://fcacommunity.force.com/RAM/s/equipment-listing

just did for 05 TJ Rubicon. Received 5 pages.

 

[Little Foot]

I’ve driven JK’s with all sorts of different gear ratios and tire sizes. 35” with 3.73 is totally fine. It’s just not that fast. 4.10’s is much better but not the end all. Just don’t do 37’s with 3.73’s. It’s horrible haha


Sent from my iPhone using Tapatalk

 

[shade]

I appreciate the feedback; I do know that autos and manuals are different, and I did do my research (5 years ago) when I was Jeep shopping. I wanted the 4.10s based on staying in the green zone of this chart. With 35s, I'd now be in the yellow zone and this is a DD and mild trail rig in BC. As suggested, I'll just do it and see how it performs. My daily driving is near sea level so I'm sure it will be fine, but it might lug when I'm in the Rockies (I just got back from a cross-country trip to New Brunswick and plan to do it again next year).

View attachment 535624

Chart Credit: https://prodigyperformance.com/blog/jeep-wrangler-gear-ratio-calculator/

I didn't mean to imply that you hadn't done any research, which you clearly have.

I think you have a good plan. Go forth and modify!

 

[jadmt]

Remember most 35’s are really and ko2 tend to run small.

 

[Happy Joe]

Don"t Micky mouse around; pull the cover (probably off the back) diff and either count the gear teeth or look at the numbers and use a calculator; then if you really want 35 inch tires (remember that most tires' diameters are not what you see on the sidewall/in advertisements (use a tape measure).
...Get out the dial indicator, along with the bearing pullers, & etc. Buy some gears then install the ratio that you want.

I completely agree; 4.10 auto Rubi; YUK!!! (Boooring). Got one; pretty disappointed; ..it needs a 4:1 first geared 5 speed manual (Fun). it is OK with 30-31s on the street but 35s , no way!, at least for me... 33's would be very marginal (street drive-ability wise, IMO. (Mine also needs upgraded brakes, anti-sway bars and carriers (ARB's) in the axles, along with roll cage reinforcement, to be really fit for off road entertainment).
My last 35 inch tired JEEP worked very well with a 4:1 first, 5 speed and 4.56 gears (& ARBS)... the 4.10 auto Rubi is a step in the wrong direction, IMO. Although it (the Rubi) is a step up from a stock, bread an butter/grocery getter jeep product.

Enjoy!

 

[Buliwyf]

If I drop $3000+ to regear, I'm going all the way into the blue zone on that chart.

3.73 to 4.30 isn't worth the cash.

 

[shade]

If I drop $3000+ to regear, I'm going all the way into the blue zone on that chart.

3.73 to 4.30 isn't worth the cash.

That was kind of my point, too. If @Jurfie has decided on a lift & tyres, picking the right ratio after the lift makes the most sense, IMO. Unlike installing a lift before larger tyres have clearance, this is a change that can be delayed and made as part of a progression. Helps with financing it, too.

I can understand frustration borne of (possibly - ought to get that figured out to establish a baseline) buying a Jeep with different differential gearing than expected, but I'd imagine it'd be far worse to change the OEM gearing, only to realize it didn't deliver the desired result.

 

[Jurfie]

I can understand frustration borne of (possibly - ought to get that figured out to establish a baseline) buying a Jeep with different differential gearing than expected, but I'd imagine it'd be far worse to change the OEM gearing, only to realize it didn't deliver the desired result.

To clarify: this is exactly my point. I thought I had 4.10s, but turns out I have 3.73s; I was wrong. Not the end of the world, but 4.10s would have been a better ratio (for me) than 3.73s as a starting point. Just like 3.73s would be better than 3.21s as a starting point. The closer I am (or thought I was) to the sweet spot would have meant not needing to regear, or at least have it not as bad to allow me to live with it for now. Realistically, 4.56 is probably what I would be considering to regear to at this point.

I appreciate the helpful comments; I learned something I didn't know (i.e. auto option replaces the 4.10s). Those who feel the need to bash the transmission choice: not so much. To each their own; it's my Jeep and I don't care if you like it. I've seen lots of configurations/modifications/bolt-ons that don't float my boat, but I don't make a point to ******** on someone else's choices. But hey, maybe I'm not as cool as you guys.