Recommended re-gear for 31" tires?

Also - the other question I had was that with my H&R springs.. will it throw off my alighnment of my track bar if it's not an adjustable track bar? I know 1-1/5"'s may not seem like a lot but it's something I want to consider as well.
I replaced mine with an OEM style - Moog DS1235, the same one you linked above. If the axle is off center at all from the 1.5" of lift, I can't tell.
 
Hi everyone,

First time poster and long tim reader of the forum. I will be doing some upgrading to my Jeep tj and wanted to get some advice from you guys on what route I should go.

my current Jeep is a 1998 Sahara 4.0L manual 5 spd. It’s currently 3.07 gears. My current tires are 225/75/15 with no lift. I’m looking to upgrade to 31 inch tires with no lift, but was thinking that I should regear as even with the current tires I feel that the Jeep can be a little sluggish, especially uphill.

from posts I’ve read it looks like a lot of people recommend regearing to 4.10 for my Jeep.. do you guys think this is the right way to go? Will I see a noticeable difference when I regea?

thank you in advance to everyone
I'VE BEEN RUNNING 4.56. GEARS W/ AIR LOCKERS AND 35 AND 37 INCH TIRES SINCE 2000 ON MY 2000TJ W/ NV3550 5 SPEED. IT'S BEEN FAULTLESS.
 
Also - the other question I had was that with my H&R springs.. will it throw off my alighnment of my track bar if it's not an adjustable track bar? I know 1-1/5"'s may not seem like a lot but it's something I want to consider as well.
I replaced mine with an OEM style - Moog DS1235, the same one you linked above. If the axle is off center at all from the 1.5" of lift, I can't tell.

I'm glad to hear that. Did you replace the back at all? If so, which part did you use?
 
Also - the other question I had was that with my H&R springs.. will it throw off my alighnment of my track bar if it's not an adjustable track bar? I know 1-1/5"'s may not seem like a lot but it's something I want to consider as well.
I replaced mine with an OEM style - Moog DS1235, the same one you linked above. If the axle is off center at all from the 1.5" of lift, I can't tell.

I'm glad to hear that. Did you replace the back at all? If so, which part did you use?
 
Also - the other question I had was that with my H&R springs.. will it throw off my alighnment of my track bar if it's not an adjustable track bar? I know 1-1/5"'s may not seem like a lot but it's something I want to consider as well.


I'm glad to hear that. Did you replace the back at all? If so, which part did you use?
No, I didn't replace the rear track bar, still running the stock one.

From what I recall, the amount the axle will shift on a lift that's 1"-1.5" is something in the 1/4" to 1/2" range. I'm no expert, but I don't think it affects front end alignment; possibly a little bit on the alignment of front to rear, but mine was all within spec after I finished.
 
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That one looks good - but I'm not sure if I'm gonna get 1.5"'s of lift (or if it even matters). I did see this rough country one, which is for 0-3.5 inches of lift. Let me know what you think..

https://www.amazon.com/dp/B00OPEUP4I/?tag=wranglerorg-20
No, I didn't replace the rear track bar, still running the stock one.

From what I recall, the amount the axle will shift on a lift that's 1"-1.5" is something in the 1/4" to 1/2" range. I'm no expert, but I don't think it affects front end alignment; possibly a little bit on the alignment of front to rear, but mine was all within spec after I finished.

Yeah I think I’m gonna go with the Moog.. sounds like a good option and I think my Jeep needs a new one
 
Hi everyone,

First time poster and long tim reader of the forum. I will be doing some upgrading to my Jeep tj and wanted to get some advice from you guys on what route I should go.

my current Jeep is a 1998 Sahara 4.0L manual 5 spd. It’s currently 3.07 gears. My current tires are 225/75/15 with no lift. I’m looking to upgrade to 31 inch tires with no lift, but was thinking that I should regear as even with the current tires I feel that the Jeep can be a little sluggish, especially uphill.

from posts I’ve read it looks like a lot of people recommend regearing to 4.10 for my Jeep.. do you guys think this is the right way to go? Will I see a noticeable difference when I regea?

thank you in advance to everyone
I am one of the few who will recommend a taller gear over a lower gear. I have a Rubi and it is a daily driver. I go off road in BC to access that perfect beach or mountain cliff to camp on but I never even consider climbing a waterfall. I love watching competitions over boulder fields but my TJR will never go there. So gearing, I had a YJ with 33s and 3.07s for 15 years and never used 5th gear but 4LO was like driving a Mustang on forestry roads, which is my passion. 60mph in 4LL on a billy goat trail.

You don't say where you drive, how you use your TJ. But for me, 33s on a daily driver, the practical ratio is 3.73. If you go deeper I hope you are not daily driving and I hope you are looking for more extreme adventures, like the Rubicon and similar trails often.

No matter what you do, go here first and figure out what rpm you are comfortable with.

http://www.grimmjeeper.com/gears.html
 
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4.0 - 6spd runnin 31's with 265-75-16 & 3:07's NO POWER issues at all. If your doing any highway driving at all 4:10's will scream at 60 mph or less with a 5spd & suck gas better and faster then any woman you know can suck !!! ;)
Agreed 100%, with my TJR, 4.10s and 33s, Im always wishing for another gear. At 65mph on a straight, flat highway there zero need for 2300rpm on the Interstate. 1900 would be perfect..... which was what my YJ turned in 4th gear. in 5th it wanted 1600rpm which was waayyy too low.

Use the Grimm Jeeper gear ratio calculator, and the input from this thread, and drive your Jeep, figure out your priorities, this is a big investment, get it right.

Get it right for how you use your Jeep.
 
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I must be a total retard because that GRC is way past me to figure out what goes in most of those spots
 
No, I didn't replace the rear track bar, still running the stock one.

From what I recall, the amount the axle will shift on a lift that's 1"-1.5" is something in the 1/4" to 1/2" range. I'm no expert, but I don't think it affects front end alignment; possibly a little bit on the alignment of front to rear, but mine was all within spec after I finished.

I went ahead and purchased the Moog track bar. Did it come with all the necessary hardware for you to install?
 
Have someone help you do a steering test. Turn the wheel back and forth with the engine off just enough to barely start moving the tires. You look at the suspension/ steering while they move the wheel. Look for anything that moves that shouldn't or looks loose.
Completely agree but one step further- look at each joint and if you can safely put your hand on both sides at the same time you will feel even more than the eye will detect.
 
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Also - the other question I had was that with my H&R springs.. will it throw off my alighnment of my track bar if it's not an adjustable track bar? I know 1-1/5"'s may not seem like a lot but it's something I want to consider as well.
It may, but it’s unlikely being that it’s one inch. Someone who has them would need to chime in.

The only thing that you can do if it does move, is to purchase one that is adjustable.
 
I will be doing some upgrading to my Jeep tj and wanted to get some advice from you guys on what route I should go
Well....you could take this route.

RioRanchoCommute.jpg
 
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Hey Guys, just wanted to give you an update on the progress. Worked on the car yesterday all day with my father-in-law. He’s very experienced with cars and works on all of his cars by himself, so I’m a little lucky to have had that help.

What we finished yesterday:

1. Installed H&R springs and Rancho RS5000X shocks in both the front and back. Luckily after spraying all the bolts two days prior to Saturday the back upper bolts and all the other ones came out fine.The main issue we ran into was the front upper nuts.. so rusted that the shock just spins when trying to unscrew it. We ended up just cutting those off.

2. Next, we installed my Moog front suspension kit which included the tie rods and track bar (sold separately). That was another animal - not only removing the old rusted parts (we had a pickle fork but some of the ends and screws wouldn’t budge) - but also installing the new moog parts was a headache. The track bar was a fairly simple installation though. The tie rod ends and sleeve were extremely difficult to put on the new moog tie rod. Not sure if this was a product issue or what was going on with it. On one side the tie rod end went on smoothly, but the other side with the sleeve and end was a long and hard fought battle to get that thing on there.

All that’s left uninstalled from the kit is the ball joints for the front (4 total) which need to be pressed in I believe. We left that for another day.

Overall, the Jeep drives so much better!! The Plan is to have the new tires installed on Tuesday (31x10.5R15) while having the alignment done. After this is all complete, the Jeep is going back in the shop for a regear to 4.10 gears from 3.07.
 
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Hey Guys, just wanted to give you an update on the progress. Worked on the car yesterday all day with my father-in-law. He’s very experienced with cars and works on all of his cars by himself, so I’m a little lucky to have had that help.

What we finished yesterday:

1. Installed H&R springs and Rancho RS5000X shocks in both the front and back. Luckily after spraying all the bolts two days prior to Saturday the back upper bolts and all the other ones came out fine.The main issue we ran into was the front upper nuts.. so rusted that the shock just spins when trying to unscrew it. We ended up just cutting those off.

2. Next, we installed my Moog front suspension kit which included the tie rods and track bar (sold separately). That was another animal - not only removing the old rusted parts (we had a pickle fork but some of the ends and screws wouldn’t budge) - but also installing the new moog parts was a headache. The track bar was a fairly simple installation though. The tie rod ends and sleeve were extremely difficult to put on the new moog tie rod. Not sure if this was a product issue or what was going on with it. On one side the tie rod end went on smoothly, but the other side with the sleeve and end was a long and hard fought battle to get that thing on there.

All that’s left uninstalled from the kit is the ball joints for the front (4 total) which need to be pressed in I believe. We left that for another day.

Overall, the Jeep drives so much better!! The Plan is to have the new tires installed on Tuesday (31x10.5R15) while having the alignment done. After this is all complete, the Jeep is going back in the shop for a regear to 4.10 gears from 3.07.

props to this guy for stimulizing the economy!!