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Discussion Starter #1
Hey everyone. We have a 16JKR currently with Mickey Tompson MTZ metric equivalent of 35’s. They measure right short of 34 when on the Jeep. Currently still have stock 4.10 with a manual. Eventually we are going to switch to 37 KO2. We wheel a lot and it is rarely on the highway but it is driven around town when not wheeling. Got a lot of stuff to do before 37’s. What if we went to 5.13’s early with current tires? Would it suck around town? I know I will like the slow crawl. Opinions?
 

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Around town as in City or little hick town driving.....no....on the highway...yes....at 72-75 mph in my jk on 35's and 4.56 I run around 2700-2900 rpms....so you'll be higher than that at highway speed....
 

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Fenders. Nemesis. It is their smaller ones with no bracing. nemesis inners too.

Thanks for the highway info. I am tired of the 4.10s with 35’s but don’t want to regear to 4.56 then 5.13’s when we get the 37’s. Could split the difference at 4.88’s but really want 5.13’s with 37’s.
 

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We have 4.88 gears with 37's. I wish we had 5.13 gears.
I think you would be OK for a while with 5.13 gears and 35's unless you do much high speed highway driving. Is it an automatic or manual trans?
 

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Not that my opinion matters, but you should be ok. I would run 'em, especially under the circumstances you drive and the standard. I run 35's and some days wish I had gone 4.88.
 

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Let me throw this out there... I had 40's and running a 5.13's on a '13 Auto. Stepped back to a 37" and now hate the 5.13's on there for the highway. Way to high on the RPM's. When guys come in the shop looking for gears with 37's, we always recommend a 4.88. Keep in mind though there is a lot of factors that go into picking a gear. How you drive, how the Jeep is outfitted, where you live... all that plays into it.

If we can help, feel free to PM, email, or call us at anytime!

-Jason
 

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5.13's on 35's and you will be screaming' down the freeway. But, 6th gear is pretty tall on the manual, and you can always just start out in 2nd...

At 70mph, 5.13 and 34" tire... you'll be at 2800RPM...

According to the master gear chart... 5.13 and 37's (when you get there) are on the 'off-road/altitude' side of the chart. 4.88 are kind of the sweet spot and cover your 34's up to 40's.
 

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Let me throw this out there... I had 40's and running a 5.13's on a '13 Auto. Stepped back to a 37" and now hate the 5.13's on there for the highway. Way to high on the RPM's. When guys come in the shop looking for gears with 37's, we always recommend a 4.88. Keep in mind though there is a lot of factors that go into picking a gear. How you drive, how the Jeep is outfitted, where you live... all that plays into it.

If we can help, feel free to PM, email, or call us at anytime!

-Jason
It is funny how everyone can see the same experience differently. I reckon part of it is where and how you drive. We live in the mountains of the east, even the low lands around us are hilly. Elevation isn't too high, but we do get up to around 3,000 feet on a regular basis. For us, on the highway rpms were around 3,000 rpm at 80 - 85 mph. And that is typically as fast as we go on the highway. Those rpms put the motor in a good spot, where it has enough power so it can make it up most hills without having to downshift (manual trans). That allows cruise control to work. With the stock gearing cruise control was useless where we live. Additionally, we like to go out west, to places with bigger hills and higher elevation. So for us the stock 3.73 gears, even with 32" tires, was horrible. The 4.88 gears and 37's (real size 35.5") work pretty well, but one more step in the right direction would, I think, be perfect.
Another aspect is what TC do you have. Most of the gain with gearing is on road, but clearly there is an impact on off road as well. If you have the 4:1 TC you may find that taller gears are less of an issue off road, where as we have the 2.72:1 TC so the 4.88 gears are a little tall for the off roading we do.
 

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Thanks for the opinions. We took it out to EJS this year and I struggled with slow enough crawl on a really hard obstacles. Specifically on Cliffhanger. That is the only time I have wished it was an automatic as even with the 4.1 T case. I was struggling with it stalling trying to get it going on tough stuff. Neither my wife nor I use it to commute with so I think if I do go with that gearing we should be fine until we can get the 37's on there.

I still want to wear out the 35's a bit more, change out the tie rod, truss the front D44, and possibly change the ball joints before we make the change. We have already have chrome molly shafts in the rear and just put a new drag link on the front.

Thanks again. I appreciate the feedback
 

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Thanks for the opinions. We took it out to EJS this year and I struggled with slow enough crawl on a really hard obstacles. Specifically on Cliffhanger. That is the only time I have wished it was an automatic as even with the 4.1 T case. I was struggling with it stalling trying to get it going on tough stuff. Neither my wife nor I use it to commute with so I think if I do go with that gearing we should be fine until we can get the 37's on there.

I still want to wear out the 35's a bit more, change out the tie rod, truss the front D44, and possibly change the ball joints before we make the change. We have already have chrome molly shafts in the rear and just put a new drag link on the front.

Thanks again. I appreciate the feedback
I have 35's (that are actually 33.5" tall) with 4.56 gears and the manual transmission. I run trails in Moab. Mine is a sport and the 2.72:1 t-case it came with made it useless for actually crawling. I just couldn't take even moderate obstacles without stalling. So I upgraded the t-case.

The 4.3 in the Atlas is like a "one lower" gear in effect. i.e. 2nd gear with the Atlas 4.3 low is really close to 1st gear with the 2.72:1 stock t-case. And that made a difference. But what really made it a dream was going with the 4 speed Atlas. That extra low range taking my 4.3:1 down to 11.7:1 makes crawling effortless. I just point it and go. No stalling, no bouncing, no problems.

If it were my Jeep and I was going to put a manual trans Rubicon on 37's, I wouldn't do anything less than 5.13s. I would even consider 5.38's if I rarely drove it on the highway. Don't be afraid of high freeway RPMs. The engine is designed to run at higher RPMs and it won't complain a bit. 4.88's are good for mountain rock crawling on 35's. 5.13's are good for 37's. Anything less and you won't really be happy with the crawling ability unless you go super low in the t-case.
 

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I ran 5.13's and 35's(BFGs) for 2 years ('13-JK 3.6/6spd/Rubi). Was almost perfect.
A little busy at 75mph, perfect at 70mph(most common cruising speed for me), 1st gear was rarely used on the street, but was not quite low enough in the really tough stuff.
I recently moved up to 37's(BFGs), and, now I feel 5.13's "not enough" on the street.
2nd gear is just a little too tall to let out without slipping the clutch, 1st is ok, a little short, and every other gear now just lacks the "omfff". I mean it's good, but not as good as it was.

Once you get accustomed to the 5.13's on 35's... you will be disappointed with 5.13's on 37's.
I now long for 5.38's.
 

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I ran 5.13's and 35's(BFGs) for 2 years ('13-JK 3.6/6spd/Rubi). Was almost perfect.
A little busy at 75mph, perfect at 70mph(most common cruising speed for me), 1st gear was rarely used on the street, but was not quite low enough in the really tough stuff.
I recently moved up to 37's(BFGs), and, now I feel 5.13's "not enough" on the street.
2nd gear is just a little too tall to let out without slipping the clutch, 1st is ok, a little short, and every other gear now just lacks the "omfff". I mean it's good, but not as good as it was.

Once you get accustomed to the 5.13's on 35's... you will be disappointed with 5.13's on 37's.
I now long for 5.38's.
That right there is likely the only reason not to run 5.13 with 35's if you plan on moving up to 37's down the road.
 

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no one mentioned the smaller pinion gear size on the 5.13 that gets susceptible to shearing dues to its reduced diameter. And of course the resale value ....5.13 = rock crawler absolutely no highway..... I am on 4.88 right now and am at 3k rpm at 68mph on 35's occasional offroading and highway. When on the highway often wish had 4.56.....as everyone has mentioned above 4.88 is the sweet spot.....but then again it all depends on how you use your toy......study the master gearing chart well cause once you get it done you cannot go back....
 

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I plan on 4.56 with 35” tires with this new Jeep. Currently 4.10’s with stock 32” mud terrain. I drive mostly highway
 

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no one mentioned the smaller pinion gear size on the 5.13 that gets susceptible to shearing dues to its reduced diameter. And of course the resale value ....5.13 = rock crawler absolutely no highway..... I am on 4.88 right now and am at 3k rpm at 68mph on 35's occasional offroading and highway. When on the highway often wish had 4.56.....as everyone has mentioned above 4.88 is the sweet spot.....but then again it all depends on how you use your toy......study the master gearing chart well cause once you get it done you cannot go back....
You've either got the smallest 35's of all time, aka less than 33", or your speedo is not calibrated, or, the shop put 5.13's in your rig and told you they are 4.88's.
With 35" BFG km2s (33.25" on the gear setting to dial the speedo correctly) and 5.13's I ran 2850rpm at 70mph... 2950rpm at 72mph and 3100rpm at 75mph.
I put 26k miles on my Jeep in 8 months, all highway driving, and averaged over 18mpg's and the rig never missed a beat.
I also think the small pinion argument is internet myth made up by people to justify not going deeper, and now believed by the masses. If you are stripping gears/breaking pinions you are going out of your way to abuse your vehicle, or, simply don't know what bind is and trying to power through it. Either way you are going to snap u-joints before you strip teeth off the gear or break a pinion.
 

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no one mentioned the smaller pinion gear size on the 5.13 that gets susceptible to shearing dues to its reduced diameter. And of course the resale value ....5.13 = rock crawler absolutely no highway..... I am on 4.88 right now and am at 3k rpm at 68mph on 35's occasional offroading and highway. When on the highway often wish had 4.56.....as everyone has mentioned above 4.88 is the sweet spot.....but then again it all depends on how you use your toy......study the master gearing chart well cause once you get it done you cannot go back....
I think the pinion size is still ok with the rubi D44. Its the D30 where 5.13 becomes an issue with pinion size. Similarly i think 5.38 in the D44 is where the pinion starts getting small.
 
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