Here we go again - 3.73 with 35s - how bad is it really?

[JerseyMark]

It probably won't be quite as much a difference as the change from the stock light 31s to the relatively heavy 33s especially if you go with a light 35 as others have mentioned.
So, overall, if you are ok with your current performance, it won't be that bad going to a 35.

Having said all of that, a regear is typically one of the most satisfying modifications to make. I have some experience with your exact question - My brother had a sport S JT and did the same thing, he ended up with 4.88s and relatively light "35s"(BFG KO2 315 C rated Raptor tires). When he had the 3.73s and the 35s, it felt sluggish. When he went to the 4.88s with the same tires, it was one of the most fun trucks I have driven, chirped the tires even. Also, the regear improved his mpg and he got 18-19mpg consistently on both city and highway compared to 16-17 with the 3.73s. Probably due to the use of the full 8 gears and the engine being in a more efficient range most of the time. He sold the truck due to having a 3rd kid and moving to a full size. He still talks about how much he misses it with that tire/gear combo.

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[jmdusza01]

It's getting to that time where I'm interested in doing another Jeep mod no my 22 Sport S.

I currently run Falken Wildpeak At3w's 285/70/17 with a Teraflex 1.5 level - but am looking to beef up the tires to a 35.

I do have the Sport S - so I have the 'dreaded' 3.73 gear ratio.

I don't go off road. I live in Wisconsin and see rolling hills from time to time....

I use my JT as my DD - primarily driving to work and back (15mins).

I don't do any heavy hauling/towing - just the typical weekend camping / hunting trips,

I'm currently averaging about 18mpg with primarily city driving...

I'd like to know for those who have had 35s and 3.73 - how bad of an idea it would be to pursue a setup like this? I have the ability to recalibrate tire size into the JT computer. But how bad will it be in the city? How bad will it be on the freeway? I am not a speed demon nor do I have a heavy foot....

I'm not sure what 35in tire to go for at the moment, but it will NOT be the AT4w due to the weight. I would like to find something that is rated well, but not overly heavy....

I have read everything form the JT will be a "dog" to "fine" when searching through the forum. I'm sure it is an individualized judgement, but I'd like a little more clarity before dropping big moolah on tires....

Thanks!

 

[TheSolarWizard]

Idk how Yall are running 4.88s on 35s
Even 4.56s on 37s is slightly more gearing than the JT has stock for a sport

(31s/3.73s on left 37s/4.56 right)

That chart makes 4.88s seem like the obvious choice.

Personally I think the gas V6 is gutless and wants to live on the moon rpm wise just to not be that guy in traffic. That can be solved via the transmission tap dancing all over its ranges or you can do it in the diffs.

OP: find some bronco 35 take offs. They are light weight, junk offroad but look decent and shouldn’t be more than $600 for a set with low miles.
And start saving for gears

 

[arosen1997]

That chart makes 4.88s seem like the obvious choice.

Personally I think the gas V6 is gutless and wants to live on the moon rpm wise just to not be that guy in traffic. That can be solved via the transmission tap dancing all over its ranges or you can do it in the diffs.

I would just be worried about overspeeding/overheating the pinion bearing.
The one I ripped out when I did the regear on mine already shows signs of overheating. I mean, I have suspicions of mine not being assembled correctly from the factory anyway, but going with 4.88s on 35s is already 20% higher pinion speed than stock for the same given driving speed. I'd rather the transmission that has active cooling rather than the passive cooling on the diff pick up those extra RPMs and load.

 

[Wheelin98TJ]

I would just be worried about overspeeding/overheating the pinion bearing.
The one I ripped out when I did the regear on mine already shows signs of overheating. I mean, I have suspicions of mine not being assembled correctly from the factory anyway, but going with 4.88s on 35s is already 20% higher pinion speed than stock for the same given driving speed. I'd rather the transmission that has active cooling rather than the passive cooling on the diff pick up those extra RPMs and load.

People have been running 4.88 with 35" tires for a very long time. Pinion bearing issues due to pinion speed are not a thing.

 

[arosen1997]

People have been running 4.88 with 35" tires for a very long time. Pinion bearing issues due to pinion speed are not a thing.

The bearing setup changed from older axles when Dana swapped to the Advantek. The pinion bearing changed from a tapered roller bearing to a double row angular contact ball bearing. So while yes they have, the bearing setup currently in the Advantek axles is only ~6 years old.

 

[Sandman 4x4]

It's getting to that time where I'm interested in doing another Jeep mod no my 22 Sport S.

I currently run Falken Wildpeak At3w's 285/70/17 with a Teraflex 1.5 level - but am looking to beef up the tires to a 35.

I do have the Sport S - so I have the 'dreaded' 3.73 gear ratio.

I don't go off road. I live in Wisconsin and see rolling hills from time to time....

I use my JT as my DD - primarily driving to work and back (15mins).

I don't do any heavy hauling/towing - just the typical weekend camping / hunting trips,

I'm currently averaging about 18mpg with primarily city driving...

I'd like to know for those who have had 35s and 3.73 - how bad of an idea it would be to pursue a setup like this? I have the ability to recalibrate tire size into the JT computer. But how bad will it be in the city? How bad will it be on the freeway? I am not a speed demon nor do I have a heavy foot....

I'm not sure what 35in tire to go for at the moment, but it will NOT be the AT4w due to the weight. I would like to find something that is rated well, but not overly heavy....

I have read everything form the JT will be a "dog" to "fine" when searching through the forum. I'm sure it is an individualized judgement, but I'd like a little more clarity before dropping big moolah on tires....

Thanks!

If weight is a concern, as well it should be, then don’t go any bigger than 17” wheels, preferably a forged aluminum alloy if you must replace the wheels. Although I have a Sport S myself with the dark grey 17x9 alloy wheels that I consider just fine. Although not sure of their weight, but pretty sure not much heavier than any aftermarket reg cast aluminum wheels available. The difference in weight between a high end forged and reg cast aluminum wheel could be around 5 lbs less for the forged each! Plus the 17” tires are more price worthy than anything bigger, plus bigger wheels and tires weigh considerably more. The width of a tire also adds weight. So try to consider a tire size like 255/80-17 at 33.1” a nice compromise. Anything wider/bigger will effect your mileage more.

 

[wannajeep]

I wouldn't do 35 with a 3.73.

I've owned several Jeeps in various configs since 2010. I think these rigs are already "on the edge" from the factory, in the name of fuel economy and cost savings (for the manufacturer). There's not much buffer left. Motors run leaner and hotter; gears run taller; hp and torque are good when you're not loaded down with passengers or cargo.

If you bump up tire size and then find yourself never using the highest gear, that's a sign.

My JT Rubicon was bone stock with 33s and a 4.10, and manual 6-speed, and it did well. Absolutely loved it but in 2WD It did not have much power or torque to spare.

 

[Bjeepz]

Hey OP, how do you like this big waste of time you have on your hands lol! Get the tires, you're gonna be fine!

 

[Trauma PA]

So a month later how are you feeling with the setup? Does it feel normal and just fine now?

It honestly does. Mind you I do live in a part of Florida which is pretty much flat minus bridges and overpasses. One of my previous JTs was a Rubicon with 4.10 gears and 35s and my current set up feels equally as good if not better. I think what has helped was choosing a lighter wheel + tire combo. Does it mean I will never re gear? No it doesn’t but there is no urgency.

 

[Doum]

It's getting to that time where I'm interested in doing another Jeep mod no my 22 Sport S.

I currently run Falken Wildpeak At3w's 285/70/17 with a Teraflex 1.5 level - but am looking to beef up the tires to a 35.

I do have the Sport S - so I have the 'dreaded' 3.73 gear ratio.

I don't go off road. I live in Wisconsin and see rolling hills from time to time....

I use my JT as my DD - primarily driving to work and back (15mins).

I don't do any heavy hauling/towing - just the typical weekend camping / hunting trips,

I'm currently averaging about 18mpg with primarily city driving...

I'd like to know for those who have had 35s and 3.73 - how bad of an idea it would be to pursue a setup like this? I have the ability to recalibrate tire size into the JT computer. But how bad will it be in the city? How bad will it be on the freeway? I am not a speed demon nor do I have a heavy foot....

I'm not sure what 35in tire to go for at the moment, but it will NOT be the AT4w due to the weight. I would like to find something that is rated well, but not overly heavy....

I have read everything form the JT will be a "dog" to "fine" when searching through the forum. I'm sure it is an individualized judgement, but I'd like a little more clarity before dropping big moolah on tires....

Thanks!

I am running 35 on my 2020 with 2 inch lift plus spacer leveler . I am doing 13 in town and 20 mpg highway at speed limit. If it's windy lol well this thing has the sand aerodinamic than a sea container

 

[Doum]

It's getting to that time where I'm interested in doing another Jeep mod no my 22 Sport S.

I currently run Falken Wildpeak At3w's 285/70/17 with a Teraflex 1.5 level - but am looking to beef up the tires to a 35.

I do have the Sport S - so I have the 'dreaded' 3.73 gear ratio.

I don't go off road. I live in Wisconsin and see rolling hills from time to time....

I use my JT as my DD - primarily driving to work and back (15mins).

I don't do any heavy hauling/towing - just the typical weekend camping / hunting trips,

I'm currently averaging about 18mpg with primarily city driving...

I'd like to know for those who have had 35s and 3.73 - how bad of an idea it would be to pursue a setup like this? I have the ability to recalibrate tire size into the JT computer. But how bad will it be in the city? How bad will it be on the freeway? I am not a speed demon nor do I have a heavy foot....

I'm not sure what 35in tire to go for at the moment, but it will NOT be the AT4w due to the weight. I would like to find something that is rated well, but not overly heavy....

I have read everything form the JT will be a "dog" to "fine" when searching through the forum. I'm sure it is an individualized judgement, but I'd like a little more clarity before dropping big moolah on tires....

Thanks!

I have 2 inches lift mopar plus leveler on 35 with 3.73 I do 21.4 mpg on hiway if I follow speed limit. In town I do 15.7 I average 13.5 with that set up in the last 13500km ots comfortable personally love the ride. All my under parts in front are well maintained. No death wobble ever. I have zero movement on my stearing wheel. And I feel the ride is quit good not that over noisy. I don't know if it's the lift but i do t hear anything I run on k02 and it's quitte there is no road noise. On hard wind of course it is still a sea co tainer shape lol

 

[Doum]

I am running 35 on my 2020 with 2 inch lift plus spacer leveler . I am doing 13 in town and 20 mpg highway at speed limit. If it's windy lol well this thing has the sand aerodinamic than a sea container

Correction I mean 21.4 on highway ..

 

[Jccook777]

Recently put 35” Mickey Thompson ATs on my sport S with 3.73 gears and a 2.5” metalcloak lift. I see about 15.5mpg in Oklahoma. I swapped from 33” Patagonia ATr’s, I was only seeing 15.9mpg on those….

power is fine for me, will regear at some point but only to go to 37s. I would have went 37s on 3.73s but from what I understand I wouldn’t be able to pull my camper with it. Ultimately chose 35s.

 

[JDK]

It's getting to that time where I'm interested in doing another Jeep mod no my 22 Sport S.

I currently run Falken Wildpeak At3w's 285/70/17 with a Teraflex 1.5 level - but am looking to beef up the tires to a 35.

I do have the Sport S - so I have the 'dreaded' 3.73 gear ratio.

I don't go off road. I live in Wisconsin and see rolling hills from time to time....

I use my JT as my DD - primarily driving to work and back (15mins).

I don't do any heavy hauling/towing - just the typical weekend camping / hunting trips,

I'm currently averaging about 18mpg with primarily city driving...

I'd like to know for those who have had 35s and 3.73 - how bad of an idea it would be to pursue a setup like this? I have the ability to recalibrate tire size into the JT computer. But how bad will it be in the city? How bad will it be on the freeway? I am not a speed demon nor do I have a heavy foot....

I'm not sure what 35in tire to go for at the moment, but it will NOT be the AT4w due to the weight. I would like to find something that is rated well, but not overly heavy....

I have read everything form the JT will be a "dog" to "fine" when searching through the forum. I'm sure it is an individualized judgement, but I'd like a little more clarity before dropping big moolah on tires....

Thanks!

I went with some 315 Goodyear Territory MT (great deal from Discount Tire). Same tire on the Bronco’s. It’s a relatively light tire for a 315. Wouldn’t want to abuse them on rocks, as I don’t think they would holdup.
I was surprised at how little difference I’ve notice in my acceleration and MPG, maybe 1mpg difference. More noticeable under braking.

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