Gears & RPM - highway driving
#11
Not to throw another wrench into the equation, but what about pinion strength? I'm going to regear my 6 speed probably at the end of the summer. 4.56s on 35s would put me almost exactly to the same place I was with 4.10s and the stock 32s. 4.88s would give me a little more oomph. But I saw a comparison of pinion strength somewhere a long time ago and if memory serves me right a 4.56 pinion is stronger than a 4.88 pinion. By the time you start talking 5.38s there was a pretty considerable difference.
I don't have the original article to reference so if someone has some real data on it, please post it up.
I don't have the original article to reference so if someone has some real data on it, please post it up.
#12
JK Enthusiast
Join Date: Dec 2007
Location: Rogers, AR
Posts: 494
Likes: 0
Received 0 Likes
on
0 Posts
May 30th a bunch of us are going to Pine Barrons, come out and wheel with us and I'll let you drive mine down the highway to see how 5:13's
https://www.jk-forum.com/forums/east-coast-51/wharton-trail-ride-sat-may-30th-80675/
was he running a hemi?
https://www.jk-forum.com/forums/east-coast-51/wharton-trail-ride-sat-may-30th-80675/
was he running a hemi?
#13
JK Super Freak
Join Date: May 2008
Location: Grand Junction, CO
Posts: 1,279
Likes: 0
Received 0 Likes
on
0 Posts
Well, I never said I was going to leave mine stock I was merely just trying to figure out why AEV would say that. I already have my 5:13's in my garage, just waiting on the rest of the project list to show up
As RedNeckJeep said, do your homework/research. I have done this for a bit now and 5:13's seem to be the "best" for me given my region of the country.
Not a sermon....just a thought
As RedNeckJeep said, do your homework/research. I have done this for a bit now and 5:13's seem to be the "best" for me given my region of the country.
Not a sermon....just a thought
#15
JK Newbie
Join Date: Feb 2009
Location: Everett, Washington
Posts: 47
Likes: 0
Received 0 Likes
on
0 Posts
What I really want to know is replacing my gears with 5.13's going to fix the problem of bogging down in speed when going up hill? I'll be crusing at 75 mph and hit a up hill grade and slow down to 50 mph and I hate that lease let me know.
#16
JK Enthusiast
Join Date: Jan 2009
Location: Doswell, Virginia--- Roanoke, VA
Posts: 144
Likes: 0
Received 0 Likes
on
0 Posts
Well, I never said I was going to leave mine stock I was merely just trying to figure out why AEV would say that. I already have my 5:13's in my garage, just waiting on the rest of the project list to show up
As RedNeckJeep said, do your homework/research. I have done this for a bit now and 5:13's seem to be the "best" for me given my region of the country.
Not a sermon....just a thought
As RedNeckJeep said, do your homework/research. I have done this for a bit now and 5:13's seem to be the "best" for me given my region of the country.
Not a sermon....just a thought
What part of VA are you in?
#17
JK Newbie
Thread Starter
Join Date: Jan 2009
Location: Gilbertsville, PA
Posts: 85
Likes: 0
Received 0 Likes
on
0 Posts
I appreciate the feedback and have been researching the heck out of this. I have looked on this forum as well as others and there is a considerable amount of contradictory information out there. The gist seems to be 4.88 or 5.13 depending on who answers the question. I figured I'd talk with someone who installs ring and pinions in the JKs for a living and in each case they thought that 4.88s was the answer. No offense to anyone, but the advice of two techs that do this for a living holds a lot of weight with me as I'm sure it would with many. Unfortunately it has only added to my confusion.
#18
JK Newbie
Thread Starter
Join Date: Jan 2009
Location: Gilbertsville, PA
Posts: 85
Likes: 0
Received 0 Likes
on
0 Posts
Here's another thread asking for a recommendation running d60s and 40" tires. Interestingly enough the recommendation from SLC is for 5.13. Once again someone that installs these things for a living. Now I am really confused.
https://www.jk-forum.com/forums/modified-jk-tech-2/what-gearing-40-inch-tires-86744/
https://www.jk-forum.com/forums/modified-jk-tech-2/what-gearing-40-inch-tires-86744/
#19
JK Freak
Join Date: Aug 2007
Location: Rancho Cucamonga, Ca
Posts: 505
Likes: 0
Received 0 Likes
on
0 Posts
I recently put 5.13s in and would been bummed if I went any lower (4.88 or less) I'm at about 2400 @ 72mph. I thought it was gonna be extreme. Nope. In fact I'd gone to 5.38 if I didn't think the pinion would get too small in a D44.
#20
JK Super Freak
Join Date: May 2008
Location: Grand Junction, CO
Posts: 1,279
Likes: 0
Received 0 Likes
on
0 Posts
I appreciate the feedback and have been researching the heck out of this. I have looked on this forum as well as others and there is a considerable amount of contradictory information out there. The gist seems to be 4.88 or 5.13 depending on who answers the question. I figured I'd talk with someone who installs ring and pinions in the JKs for a living and in each case they thought that 4.88s was the answer. No offense to anyone, but the advice of two techs that do this for a living holds a lot of weight with me as I'm sure it would with many. Unfortunately it has only added to my confusion.
I can tell you what non-techs JK owners, who apparently shouldn't be listend to, have told me. I haven't come across a single person with an auto, 35's or 37's and 5.13's who wished they had went with 4.88's - not a single one. On the other hand most every automatic owner who went with 4.88's wishes they went with 5.13's. Heck I went with 5.13's and wish I 5.38's had been available and that I'd have been smart enough to go with them.
Actually it seems there is little contradiction on gears for a JK with 35's. The consensus answer is 4.88's with a stick and 5.13's for an auto. Question - if 4.88's are good behind a stick with an OD of .84 who in their right mind would choose them over 5.13's when used with a tranny with an OD of .69?
I think you're overly impressed by "experts". My experience when dealing with shops is amazement that people can be in the business and remain so ignorant.