Differential gear ratios, axles, and locker selection ?

Jeepster78

TJ Enthusiast
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Joined
Aug 8, 2021
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114
Location
Albuquerque, NM
I’m resurrecting a 2002 tj 4.0 and I’m ready to start upgrading/rebuilding my differentials Dana 30 front, Dana 35 rear soon. I have both diffs completely broken down and will be sandblasting and painting them soon. My current plan is to put a 4” Currie lift with 1” mml, sye, Currie drag link and tie rods, 1.25 savvy bl to fit 35” 12.5” x15 tires for moderate off roading not my daily driver, but will drive frequently. I have read about 1000 posts regarding gearing and 35” tires lifts ect you name it and I’ve probably read it hear, tons of info. To accommodate the 35” tires and beef up the diffs would a super 35 kit with 4.88 gears and 30 spline axels get the job done and be the best selection? I would also like to run some sort of locker most likely a lunchbox seems like a nice economical choice, but I'm open to suggestions. I would like to hear from you all the best approach without having to go to a Dana 44 and what axels, gears, lockers and reputable companies to buy said parts from are recommended for the Dana 30/35 running 35” tires.
 
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I did revolution s35 with Detroit auto locker. Also put a Detroit auto locker in the stock Dana 30 (not alot of snow in Ga). Will be upgrading the front safts at some point. I did 4.10 gears with the 32rh Trans.
 
It's strongly recommended that you NOT buy your own gears, carriers, shims, etc. Instead, have the shop that will be installing them provide ALL (!!!) of the parts so if/when something goes wrong with them during or after the install the installing shop will take care of all the issues. If you provided the parts, you might save a small amount of $$$ but the risk is that the shop will screw something up and use your parts as an excuse something isn't right.

X2 on the 5.13 since you live in Albuquerque which has a higher than typical altitude.

Yes indeed go for the Super 35 kit and X2 on the www.4LowParts.com recommendation, talk with Ricky @Garza who is a good guy and fellow Jeeper too.
 
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It's strongly recommended that you NOT buy your own gears, carriers, shims, etc. Instead, have the shop that will be installing them provide ALL (!!!) of the parts so if/when something goes wrong with them during or after the install the installing shop will take of all the issues. If you provided the parts, you might save a small amount of $$$ but the risk is that the shop will screw something up and use your parts as an excuse something isn't right.

X2 on the 5.13 since you live in Albuquerque which has a higher than typical altitude.

Yes indeed go for the Super 35 kit and X2 on the www.4LowParts.com recommendation, talk with Ricky @Garza who is a good guy and fellow Jeeper too.
You know this may be just me looking for an opportunity to say something but I think this is relevant...I make my living working on houses.

We provide all of the material that has any technical fitment, And we make decisions based on our positive experiences working with different situations over the last 20 years. We certainly factor in the job site and the finished product that we’re looking for.

We will not contract to do a job where we have no control over the material choices...We are going to use what we are trained to know how to work with and of the best quality because the body of work we creates becomes our total liability of warranty work- And in addition to the work that we produce we are also liable for damages to related components such as if a shower failed it ruins the living room hardwood behind it we’re on the hook.

I would be almost wary if the shop wanted you to provide the parts because you are giving them an out if anything goes wrong.

In addition to his input on this forum and counsel to several heads of state, Jerry has done most of his own wrenching and few people have a better grasp of understanding the parameters and nuances of making least thing to work....and the dealings that are involved in the process.
 
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I never thought of it like that, that's a very astute way to look at it. 💪
Laws vary from state to state but generally you don’t have to warranty anything that you didn’t furnish.

One day everyone will reflect back on my time here- It will look like one of those news reports when they go back to the small town of someone who tried to assassinate the president and ask people about them-

Was he dependable? Oh sure, showed up every day

Was he smart? Seemed that way sometimes

Was he courteous? Oh yes


Did he ever do anything that made you think he was a danger to himself and others? oh Absolutely, complete nut. Crazy. 😂😂😂
 
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Ya I’ve been debating weather to take on the regear myself or outsource it. I have watched a bunch of YouTube videos and have just about convinced myself to take the task on myself but who knows I may change my mind by the time I’m ready to pull the trigger and regear. Thanks for the responses this far. I will call 4low parts tomorrow and see what they have to offer.
 
Ya I’ve been debating weather to take on the regear myself or outsource it. I have watched a bunch of YouTube videos and have just about convinced myself to take the task on myself but who knows I may change my mind by the time I’m ready to pull the trigger and regear. Thanks for the responses this far. I will call 4low parts tomorrow and see what they have to offer.
I absolutely loved the positive results I got from regearing my TJ...If you’re going to run larger tires it is the only practical way to get the designed power train performance back.

I did not enjoy trying to do it myself.

I’m not trying to belittle the idea of watching a video but I’m going to make a comparison by saying that if someone watched the videos of open-heart surgery I still would not want them to operate on me.

A video just doesn’t help you when you’ve got an oily 40 pound carrier gear in your hands and shims are falling out. It goes from buddy time in the garage to more like emergency childbirth real fast.
 
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+1 on having the shop to provide the parts.

No offense to AndyG, but for the most part, mechanics and builders are in a sneaky and a stingy type of business that is ready to fuck you over anything and then blame you for everything. Give them the least amount of options to get out of the situation.

"best selection" is a vague, broad, bias and situational term. When you find that "best", please share, i would truly love to have a look at it. Other than that, yes, super 35 is a good and proven option.
 
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Ya I’ve been debating weather to take on the regear myself or outsource it. I have watched a bunch of YouTube videos and have just about convinced myself to take the task on myself but who knows I may change my mind by the time I’m ready to pull the trigger and regear. Thanks for the responses this far. I will call 4low parts tomorrow and see what they have to offer.
Go for it, thumbs up, i cheer for you.

Here is recent thread on it, it may motivate you.
https://wranglertjforum.com/threads/re-gear-advice.54131/#post-945094
 
+1 on having the shop to provide the parts.

No offense to AndyG, but for the most part, mechanics and builders are in a sneaky and a stingy type of business that is ready to fuck you over anything and then blame you for everything. Give them the least amount of options to get out of the situation.

"best selection" is a vague, broad, bias and situational term. When you find that "best", please share, i would truly love to have a look at it. Other than that, yes, super 35 is a good and proven option.
Yes- there is a lot of truth in that and probably the biggest weakness of a fixed cost type of contract is that it gives the shop or the builder the incentive to increase profit by cutting costs-

We developed a hybrid contract that has been very successful where the labor is known ahead of time, based on what we expect to work with, and then we help the client with selections and finalize the material costs and any added labor costs they incur, in writing. Works beautiful, but we still have to stress where cost increases are happening.
 
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Does anyone have a good ph number or email for 4low parts I’ve tried calling the Costomer service number and left a message 3days ago but can’t get ahold of anyone to ask a few questions before ordering the correct parts.