Re-gearing

I have an '05 with 6spd, 231, on 35's currently running 4.88.
I run about 2800 rpm at 70 mph.
 
06 LJ, 6-speed, 35" MT/Rs...

My suggestion would be 5.13's.
 
There seems to be a lot of varying opinions on the internet for the ideal gear ratio for a jeep with 35s and the 6 speed. I guess it also depends on the added weight, any towing, elevation/terrain. I don't have a right answer but some research is about all I can provide at this point until I regear myself.

The thread below from 2012 has quite a few people recommending 4.56 and 4.88. Savvy in the thread below is recommending 4.56s with 35s and the 6 speed if you drive on the road much. Mentioning they actually switched from 4.88 back to 4.56 which is interesting. Granted it's an older thread.

I have a 6 speed lj, 35s and 3.73 and don't use 6th much unless I am running 75 or higher. I want to regear eventually though and thinking 4.88s would be good since the math works out to about 4.71 ratio for a Rubicon 6speed to get back to stock with 35s.

Those that have or currently run 4.88s and 6 speed manual, was it enough gearing? The final overdrive gear is only .84 on the 6 speed I believe.

I have a buddy with an ax15 and 4.56 with 35s that does well on and off road.

https://www.jeepforum.com/forum/f9/...d-rubicon-unlimited-1424083/index2.html?amp=1
 
Longwhitejeep said:
There seems to be a lot of varying opinions on the internet for the ideal gear ratio for a jeep with 35s and the 6 speed. I guess it also depends on the added weight, any towing, elevation/terrain. I don't have a right answer but some research is about all I can provide at this point until I regear myself.

The thread below from 2012 has quite a few people recommending 4.56 and 4.88. Savvy in the thread below is recommending 4.56s with 35s and the 6 speed if you drive on the road much. Mentioning they actually switched from 4.88 back to 4.56 which is interesting. Granted it's an older thread.

I have a 6 speed lj, 35s and 3.73 and don't use 6th much unless I am running 75 or higher. I want to regear eventually though and thinking 4.88s would be good since the math works out to about 4.71 ratio for a Rubicon 6speed to get back to stock with 35s.

Those that have or currently run 4.88s and 6 speed manual, was it enough gearing? The final overdrive gear is only .84 on the 6 speed I believe.

I have a buddy with an ax15 and 4.56 with 35s that does well on and off road.

https://www.jeepforum.com/forum/f9/...d-rubicon-unlimited-1424083/index2.html?amp=1
Click to expand...
Lots of things to consider like you said, and really a lot of people will recommend what they have simply because it's what they have and know.

Right off the bat, I would recommend dropping 4.56 from consideration. It is about equivalent with the 5 speed and 4.88s all else being equal. That was a good ratio for a long time and for a really long time, was simply the lowest option. Then 5.13 came around and slowly people started wondering if maybe it would be even better. Many have gone to 5.13's with 35's and 5 speeds and been very pleased. And as such, they adjusted the 33's to happily run 4.88's as well. Even just 3-4 years ago, 5.13/35/5MT was pretty unpopular. Over time, people have started taking the plunge and I haven't seen anyone be disappointed.

Now for the 6 speed, the 4.88 you are considering is about the same as 5.13 & 5 speed. Tires being equal (34" actual measurement), the 6 speed with 4.88 is actually 30 rpm higher at 70 than 5 speed with 5.13. So if they 5 speed guys are happy that way, you can assume you would be too.

Now taking the 6 speed to 5.13 with 35's, that is basically another gearing step lower, almost as if a 5 speed were running 5.38. Not a lot of people have that combo but there are definitely a handful (the guys in this thread to start) and they are happy too.

Overall I don't think you would go wrong either way, but I do think 4.56 would be somewhat a mistake. The guys back in 2012 regeared backwards as you said, and maybe they liked it that way, but it could have just been the era. Back then 4.88 was real popular with the 5 speed so many were used to that rpm level (the same as 6 speed & 4.56), so maybe they just wanted to go back to what they were used to. I don't see anybody on this forum, 9 years later, regretting 4.88 or 5.13, so I think mainly it's about what you're used to, and what you have, and what you need it for.

It also just depends on the situation on how you got your gears. Some people buy axles and run what they have in them. Some swap across different builds they do, etc. If I were set on 4.88 and found axles with 5.13, guaranteed I'd just run the 5.13s.

For you, I think you could go 4.88 or 5.13 and be happy with it either way. 5.13 if you deal with more hilly stuff or more crawling, or really like to enjoy lower gear pep.
 
  • Like
Reactions: Longwhitejeep
machoheadgames said:
Lots of things to consider like you said, and really a lot of people will recommend what they have simply because it's what they have and know.

Right off the bat, I would recommend dropping 4.56 from consideration. It is about equivalent with the 5 speed and 4.88s all else being equal. That was a good ratio for a long time and for a really long time, was simply the lowest option. Then 5.13 came around and slowly people started wondering if maybe it would be even better. Many have gone to 5.13's with 35's and 5 speeds and been very pleased. And as such, they adjusted the 33's to happily run 4.88's as well. Even just 3-4 years ago, 5.13/35/5MT was pretty unpopular. Over time, people have started taking the plunge and I haven't seen anyone be disappointed.

Now for the 6 speed, the 4.88 you are considering is about the same as 5.13 & 5 speed. Tires being equal (34" actual measurement), the 6 speed with 4.88 is actually 30 rpm higher at 70 than 5 speed with 5.13. So if they 5 speed guys are happy that way, you can assume you would be too.

Now taking the 6 speed to 5.13 with 35's, that is basically another gearing step lower, almost as if a 5 speed were running 5.38. Not a lot of people have that combo but there are definitely a handful (the guys in this thread to start) and they are happy too.

Overall I don't think you would go wrong either way, but I do think 4.56 would be somewhat a mistake. The guys back in 2012 regeared backwards as you said, and maybe they liked it that way, but it could have just been the era. Back then 4.88 was real popular with the 5 speed so many were used to that rpm level (the same as 6 speed & 4.56), so maybe they just wanted to go back to what they were used to. I don't see anybody on this forum, 9 years later, regretting 4.88 or 5.13, so I think mainly it's about what you're used to, and what you have, and what you need it for.

It also just depends on the situation on how you got your gears. Some people buy axles and run what they have in them. Some swap across different builds they do, etc. If I were set on 4.88 and found axles with 5.13, guaranteed I'd just run the 5.13s.

For you, I think you could go 4.88 or 5.13 and be happy with it either way. 5.13 if you deal with more hilly stuff or more crawling, or really like to enjoy lower gear pep.
Click to expand...
Thanks! I agree with you. I figured things might have been updated since that thread was created. It's just something that pops up during research. That is why I like this forum!

I definitely prefer the technical crawling so might NM look into the 5.13s. I did swap in a 241or to help slow this thing down offroad.

Anyone noticing any strength differences for the dana 30 with the different ratios properly set up?
 
Longwhitejeep said:
I want to regear eventually though and thinking 4.88s would be good since the math works out to about 4.71 ratio for a Rubicon 6speed to get back to stock with 35s.
Click to expand...
Something to consider is the increased weight and rolling resistance of bigger tires and any additional weight added when building your TJ. IMO, it's better to err on the side of more gear rather than less.
 
  • Like
Reactions: Longwhitejeep
L J said:
Something to consider is the increased weight and rolling resistance of bigger tires and any additional weight added when building your TJ. IMO, it's better to err on the side of more gear rather than less.
Click to expand...
100% agree. It also seems people use to not recommend anything higher than a 4.88 for the dana 30 due to strength issues.
 
  • Like
Reactions: L J
Longwhitejeep said:
It also seems people use to not recommend anything higher than a 4.88 for the dana 30 due to strength issues.
Click to expand...
Not a problem at all using 5.13 in the Dana 30, it's done all the time and everything holds up fine. Everyone was saying the same thing when 4.88 gearing came out for our axles, many were claiming our axles weren't strong enough for them either. 5.13 is very commonly installed into our TJ Dana 30 axles, especially those with the 42RLE transmission.

P.S. Ratio-wise, 5.13 is a lower ratio than 4.88 is.
 
  • Like
Reactions: Longwhitejeep
Jerry Bransford said:
Not a problem at all using 5.13 in the Dana 30, it's done all the time and everything holds up fine. Everyone was saying the same thing when 4.88 gearing came out for our axles, many were claiming our axles weren't strong enough for them either. 5.13 is very commonly installed into our TJ Dana 30 axles, especially those with the 42RLE transmission.

P.S. Ratio-wise, 5.13 is a lower ratio than 4.88 is.
Click to expand...
Thanks Jerry. I did mean a lower ratio, numerically higher. Didn't mean to confuse anyone.

Everyone also seems to be recommending tons for any axle changes lately. "Could've gone to tons for that price"
It's always interesting to see what the real world shows overtime vs what the internet says 😆.
 
Longwhitejeep said:
Thanks Jerry. I did mean a lower ratio, numerically higher. Didn't mean to confuse anyone.

Everyone also seems to be recommending tons for any axle changes lately. "Could've gone to tons for that price"
It's always interesting to see what the real world shows overtime vs what the internet says 😆.
Click to expand...
My bet is many who are recommending "tons" are running stock axles on easy trails but who want to sound cool. If I win the lottery I'll be installing them and 40's but in the mean time, my axles are holding up very well to 35's, lockers, and tough trails.
 
Jerry Bransford said:
My bet is many who are recommending "tons" are running stock axles on easy trails but who want to sound cool. If I win the lottery I'll be installing them and 40's but in the mean time, my axles are holding up very well to 35's, lockers, and tough trails.
Click to expand...
Keyboard warriors for sure. Barnes 4wd just did a video on it the other day. How everything doesn't need 1 tons to go wheeling.

 
Longwhitejeep said:
Thanks Jerry. I did mean a lower ratio, numerically higher. Didn't mean to confuse anyone.

Everyone also seems to be recommending tons for any axle changes lately. "Could've gone to tons for that price"
It's always interesting to see what the real world shows overtime vs what the internet says 😆.
Click to expand...
I have "tons" on order now. Not cost effective at all. If you aren't going bigger than 35's ignore any "ton" comments.
 
Top Bottom
Back