4.10's and 35's?
05-04-2008, 08:07 PM
#11
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I too am running 35's w/4.10 on a 4-dr Rubi with auto-trans. On the freeway on-ramps I typically turn OD off to get the dog up-to speed. Off-Road it's fine. Based on a tire size/gear ratio calculator program I have, going to 4.56 for 35's will take you back to a stock tire/gear overall ratio and get your gas mileage closer to stock as well. I'm considering the higher gear sets as well....but with just a little more than 1K miles on my new rig, I'll wail and just pour more $ into bumpers and other expensive things like GAS!
05-05-2008, 04:55 AM
#12
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hey guys i have a 2dr "x" with 4.10 gears. i will be getting new tires soon and was wondering if 35's are going to make my jeep a dog on the highway. i currently have 33's but just want a bigger tire. does anyone have this setup and if so hows the mileage, acceleration, and any breakage yet?
To save you the hassle of looking. The over all consensuses is on than just this board is
5.13 for both auto & manual
But if you are worried about gas (not much dif)
5.13=auto
4.88=manual
05-05-2008, 07:09 AM
#13
JK Super Freak
I have a new stock '08 with a 6 spd and 3.73 gears - 4 dr - When on flat terrain, I can cruise at 60-70 mph in 6th even on slight hills, etc.
When in the mountains, ok, Pocono's.like Rousch Creek, etc...I have to floor it on grades and drop it a gear or two to maintain speed.
The torque peak for the V6 is closer to 4k than to the 2K or so the rpm would be at at reasonable cruise speeds.
So, the STOCK JK has to be downshifted to maintain speed on grades, to get the rpm up to where it can tackle the torque needed, etc....about two gears worth.
Of course, if I dropped in 5.13's to replace the 3.73's...
It would raise the rpm ~ 27.3%, or from ~ 2,000 rpm to ~ 2,546 rpm for the same speed in 6th.
That's roughly a one gear drop/RPM rise equivalent.
Of course, that also means that on FLATTER terrain, I'm ALSO essentially runnning a gear low...but have no gears left to shift UP with...so my MPG drops, etc.
____________________________________
What this means is that the JK's in Colorado, in the land of steep hills and thin air, are going to think flat landers are insane for thinking a gear choice is "OK"....and flat landers will have trouble figuring out why these other JK's need such low gearing, etc.
Those not familiar with smaller power plants, etc....who feel that if they have to down shift to maintain speed on a steep grade, etc, that the damn thing must be broken....will feel that it needs lowers gears, so that they do not have to down shift to maintain speed on grades, etc.
And that's STOCK.
Add taller tires, and holy moly, the discrepancy widens.
Me, taller tires tend to simply deepen the overdrive, improve MPG up to about 35's...then - the extra rotational masses, and lift related wind resistance, etc...tend to out weight the overdrive related benefits, and MPG plummets.
So, for a DD, 35's are a good limit. Of course, I LOVE taller tires OFF road, so a SECOND SET for play is a nice solution, that way, I can tool about for work, etc, on milder tires that are more street friendly....and swap on giant aggressive mudders for when things get serious and its time for some fun.
When using the paddle wheeled monster meats to commute, the lugs get worn down too quickly, and it tends to defeat the purpose...I get them BECAUSE of the big lugs, etc....but, I end up with funny looking racing slicks when trying to off road on them.
I just use the gps as a speedometer/odometer anyway.
When in the mountains, ok, Pocono's.like Rousch Creek, etc...I have to floor it on grades and drop it a gear or two to maintain speed.
The torque peak for the V6 is closer to 4k than to the 2K or so the rpm would be at at reasonable cruise speeds.
So, the STOCK JK has to be downshifted to maintain speed on grades, to get the rpm up to where it can tackle the torque needed, etc....about two gears worth.
Of course, if I dropped in 5.13's to replace the 3.73's...
It would raise the rpm ~ 27.3%, or from ~ 2,000 rpm to ~ 2,546 rpm for the same speed in 6th.
That's roughly a one gear drop/RPM rise equivalent.
Of course, that also means that on FLATTER terrain, I'm ALSO essentially runnning a gear low...but have no gears left to shift UP with...so my MPG drops, etc.
____________________________________
What this means is that the JK's in Colorado, in the land of steep hills and thin air, are going to think flat landers are insane for thinking a gear choice is "OK"....and flat landers will have trouble figuring out why these other JK's need such low gearing, etc.
Those not familiar with smaller power plants, etc....who feel that if they have to down shift to maintain speed on a steep grade, etc, that the damn thing must be broken....will feel that it needs lowers gears, so that they do not have to down shift to maintain speed on grades, etc.
And that's STOCK.
Add taller tires, and holy moly, the discrepancy widens.
Me, taller tires tend to simply deepen the overdrive, improve MPG up to about 35's...then - the extra rotational masses, and lift related wind resistance, etc...tend to out weight the overdrive related benefits, and MPG plummets.
So, for a DD, 35's are a good limit. Of course, I LOVE taller tires OFF road, so a SECOND SET for play is a nice solution, that way, I can tool about for work, etc, on milder tires that are more street friendly....and swap on giant aggressive mudders for when things get serious and its time for some fun.
When using the paddle wheeled monster meats to commute, the lugs get worn down too quickly, and it tends to defeat the purpose...I get them BECAUSE of the big lugs, etc....but, I end up with funny looking racing slicks when trying to off road on them.
I just use the gps as a speedometer/odometer anyway.
Last edited by TEEJ; 05-05-2008 at 07:17 AM.
05-05-2008, 07:37 AM
#14
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sheesh, after reading all these posts about bigger meats on stock gears I may just settle with a set of 33's. That is until I get enough $$ for gears, but that could be several years down the road.
Lastly, newb question. How come with bigger tires you won't be able to use O/D during certain situations?
Good info on this thread so, BUMP!
Lastly, newb question. How come with bigger tires you won't be able to use O/D during certain situations?
Good info on this thread so, BUMP!
05-07-2008, 05:18 PM
#17
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I have a manual Rubicon with 35's. It drives fine. You just shift at different points. It won't win any race, but it sure will climb a steep dirt hill in 4 low. All of you guys who want extreme acceleration, why did you buy a Jeep?
05-07-2008, 05:42 PM
#18
JK Super Freak
hey guys i have a 2dr "x" with 4.10 gears. i will be getting new tires soon and was wondering if 35's are going to make my jeep a dog on the highway. i currently have 33's but just want a bigger tire. does anyone have this setup and if so hows the mileage, acceleration, and any breakage yet?
05-08-2008, 04:47 AM
#20
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I dont car about acceleration,I care about being able to use my overdrive
and not have my Jeep screaming @ 3000 RPM with O/D off to go 65/70.
I live out in the country so I am always on back country roads and it really
sucks only being able to drive 55
In order to use my O/D.