Build Advice Please

flyinfish

Woke Is A Joke!
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2004 Rubicon 25k miles and is stock except a Warn Rock Crawler rear bumper. Moab 16x8 Wheels

I'm looking to put 35x12.5 Tires on it and after a ton of reading on this forum(thanks to everyone), I started purchasing the items I know I need.

The main issue I'd like to get figured out, can I or is it not advisable to run 315/75/R16 KM2 BFG Tires on the 16x8 Moab rims. The tire spec is Dia 34.8, Width 12.3, Rim Range 8-10, Measured Rim 8.5, Load D
If I have to purchase wheels I can do that but I like the Moab wheels. I know I should probably be running beadlocks. If I do purchase wheels should I buy 17" or 15" dia. for good air down.

My other area of concern is regearing. The front and rear are both Dana 44's running 4.10 gears and a 241 transfer case. I have a 42RLE Automatic. Do I need to regear both front and rear and are 4.88 gears the best or should I go lower. I don't want to have to run the hell out of it to do highway speeds.

If anyone has an opinion, I'm all ears and would appreciate it. Below is my build list and will start Installing the lift Monday.

Purchased so far:
Currie CE-9801HS 4" complete lift kit with Currie front Anti-Rock Sway Bar.
Extended Brake Lines

To Purchase:
Currie Currectlync (Tie Rod/Drag Link System)
Body Lift - Savvy Aluminum Body Lift 1.25″
Double Cardan Driveshaft (Tom Woods)
RS5000X or RS9000XL Shocks
Wheels?
Front Bumper
Winch-Warn Zeon 10-S Platinum
 
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I see no issues running those rims.👍 Other than the 5" offset that most likely will not be in any aftermarket rims you buy. So a bit of rubbing near full lock.🧐 Easy enough to deal with. If you like those rims then why pay money to get something you don't like as much?
Re-gearing...get the 35's put on and see what you think. There are guys that have 3.07's and 35's and say they are happy.🤯 So everyone is different. I've got 4.10's and 32's on a 6 speed and am happy. Don't think I would be happy on 35's though.
 
View attachment 115074
2004 Rubicon 25k miles and is stock except a Warn Rock Crawler rear bumper. Moab 16x8 Wheels

I'm looking to put 35x12.5 Tires on it and after a ton of reading on this forum(thanks to everyone), I started purchasing the items I know I need.

The main issue I'd like to get figured out, can I or is it not advisable to run 315/75/R16 KM2 BFG Tires on the 16x8 Moab rims. The tire spec is Dia 34.8, Width 12.3, Rim Range 8-10, Measured Rim 8.5, Load D
If I have to purchase wheels I can do that but I like the Moab wheels. I know I should probably be running beadlocks. If I do purchase wheels should I buy 17" or 15" dia. for good air down.

My other area of concern is regearing. The front and rear are both Dana 44's running 4.10 gears and a 241 transfer case. I have a 42RLE Automatic. Do I need to regear both front and rear and are 4.88 gears the best or should I go higher. I don't want to have to run the hell out of it to do highway speeds.

If anyone has an opinion, I'm all ears and would appreciate it. Below is my build list and will start Installing the lift Monday.

Purchased so far:
Currie CE-9801HS 4" complete lift kit with Currie front Anti-Rock Sway Bar.
Extended Brake Lines

To Purchase:
Currie Currectlync (Tie Rod/Drag Link System)
Body Lift - Savvy Aluminum Body Lift 1.25″
Double Cardan Driveshaft (Tom Woods)
RS5000X or RS9000XL Shocks
Wheels?
Front Bumper
Winch-Warn Zeon 10-S Platinum
Your build is very close to mine, and you have picked all very good quality products. I think you will be very happy, mine drives, handles, and off road's great.

I am also running

Currie CE-9801HS 4" complete lift kit with Currie front Anti-Rock Sway Bar. SAME
Extended Brake Lines SAME
Currie Currectlync (Tie Rod/Drag Link System) SAME
Body Lift - Savvy Aluminum Body Lift 1.25″ 1" BL
Double Cardan Driveshaft (Tom Woods) STOCK
RS5000X or RS9000XL Shocks RS9000XL
Wheels? 15 x 8 WHEELS w/ 35's
Front Bumper BESTOP HIGHROCK
Winch-Warn Zeon 10-S Platinum WARN ZEON 8S

I switched to 15" wheels more tire choices and a lot less money for the same 35" tires. And yes I would recommend a re-gear, I am not sure what gears you need as mine is a 6 speed manual but I switched to 4:88's and yes you have to re-gear both front and rear. I would also recommend removing the steps and the factory steel plates and add a nice pair of rock sliders
 
I see no issues running those rims.👍 Other than the 5" offset that most likely will not be in any aftermarket rims you buy. So a bit of rubbing near full lock.🧐 Easy enough to deal with. If you like those rims then why pay money to get something you don't like as much?
Re-gearing...get the 35's put on and see what you think. There are guys that have 3.07's and 35's and say they are happy.🤯 So everyone is different. I've got 4.10's and 32's on a 6 speed and am happy. Don't think I would be happy on 35's though.
Thanks for the reply!

So if I stack three wheel spacers together I can reduce the backspace ;) Joking!

I'll just buy some wheels and do it right.

Since I have the 2004 Rubicon 42RLE I'll probably end up at 5.38 gears

Your build is very close to mine, and you have picked all very good quality products. I think you will be very happy, mine drives, handles, and off road's great.

I am also running

Currie CE-9801HS 4" complete lift kit with Currie front Anti-Rock Sway Bar. SAME
Extended Brake Lines SAME
Currie Currectlync (Tie Rod/Drag Link System) SAME
Body Lift - Savvy Aluminum Body Lift 1.25″ 1" BL
Double Cardan Driveshaft (Tom Woods) STOCK
RS5000X or RS9000XL Shocks RS9000XL
Wheels? 15 x 8 WHEELS w/ 35's
Front Bumper BESTOP HIGHROCK
Winch-Warn Zeon 10-S Platinum WARN ZEON 8S

I switched to 15" wheels more tire choices and a lot less money for the same 35" tires. And yes I would recommend a re-gear, I am not sure what gears you need as mine is a 6 speed manual but I switched to 4:88's and yes you have to re-gear both front and rear. I would also recommend removing the steps and the factory steel plates and add a nice pair of rock sliders

Nice setup you have! Thanks for the reply!

Yes, rock sliders are on my list for sure! Steps going too!
I'll probably go with 5.38 gears Did you only do the rear or both?
 
Thanks for the reply!

So if I stack three wheel spacers together I can reduce the backspace ;) Joking!

I'll just buy some wheels and do it right.

Since I have the 2004 Rubicon 42RLE I'll probably end up at 5.38 gears



Nice setup you have! Thanks for the reply!

Yes, rock sliders are on my list for sure! Steps going too!
I'll probably go with 5.38 gears Did you only do the rear or both?
You'll need to regear both front and back. They need to be the same ratio.
 
Have you wheeled it stock yet? Do you know what type of terrain you are building for? Your list may be overkill for what you actually end up using it for. Just trying to save you some money, if it matters.
 
Thanks for the clarification. I assumed so because if they weren't, the transfer case would be ruined in 4 wheel drive.


The same gears are needed front and back, but won't necessarily ruin the transfer case. 20 some years ago I ended up with mis-matched differentials. It pretty much worked fine off road but 4 hi and 4 low both acted like being in park when not moving. I always planned on correcting that but six or seven years later I sold it to someone and included the correct front axle still needing rebuilt. That gut never fixed it. It went through a number of hands after him and was raced for 18 years. Now that I have it back both 4wds acts like park. I'm not sure if it's because it's been raced with different sized tires front and back, which it still has, or maybe it still has the same axles. Why have I had it for 1 1/2 years now and never checked? I really can't say.
 
Have you wheeled it stock yet? Do you know what type of terrain you are building for? Your list may be overkill for what you actually end up using it for. Just trying to save you some money, if it matters.
I haven't four wheeled this TJ stock yet. I just bought it three weeks ago.
My four wheeling will be in the Pacific Northwest. Oregon Coast Range, Cascade Range and Eastern Oregon. I shouldn't have the large boulders and rocks like other places like Utah.
Ground clearance is important and is why I was thinking 35's otherwise 33's might be the way to go. I do want the jeep to still drive good on the road as I'd be driving on highways to get to wherever I go four wheeling.
I have a 1973 CJ-5 with a 304 in it and used it for hunting and four wheeling. The TJ should be a big improvement with coil springs, fuel injection and all the Rubicon extras that the CJ-5 doesn't have.
 
The same gears are needed front and back, but won't necessarily ruin the transfer case. 20 some years ago I ended up with mis-matched differentials. It pretty much worked fine off road but 4 hi and 4 low both acted like being in park when not moving. I always planned on correcting that but six or seven years later I sold it to someone and included the correct front axle still needing rebuilt. That gut never fixed it. It went through a number of hands after him and was raced for 18 years. Now that I have it back both 4wds acts like park. I'm not sure if it's because it's been raced with different sized tires front and back, which it still has, or maybe it still has the same axles. Why have I had it for 1 1/2 years now and never checked? I really can't say.
That's amazing you ended up getting it back!
I'll be doing both for sure.
 
I always recommend wheeling it as is first. You might be surprised at what it can do. It may change your build plans. Big difference in cost between 33s and 35s. Other than coils and shocks, I'm pretty much stock (Rubicon) on 33s. Goes everywhere I need it to (so far).

I'm curious about the extended brake lines you bought. Do you know that you need them, or is because your CJ needed them. I had the same thought when I upgraded from a CJ.
 
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If it were me, I would do a 3-4” suspension lift with 32-33” tires. Save money on all those extra parts you would buy for 35s and direct the funds towards a tummy tuck. Between the lockers, 4:1 transfer case, and tummy tuck, you’ll have a rig that could go almost anywhere.

Really the only benefit to bigger tires is higher axle clearance and more sidewalk when aired down, like if you’re doing crazy bouldering. The rest of your rig can be raised with a suspension lift.

A Rubicon is already extremely capable in stock form. A few modest mods like listed above make it damn near unstoppable.

Also if you want to ditch the 16” wheels and to keep to Moab look, you can pick up JK 17” Moabs for super cheap because the market is flooded with JK takeoffs. I got a set of 5 with 32” BFGs for $200. You’d need spacers anyways to change the lug pattern so you could cover your issue of tire rub there too.
 
I always recommend wheeling it as is first. You might be surprised at what it can do. It may change your build plans. Big difference in cost between 33s and 35s. Other than coils and shocks, I'm pretty much stock (Rubicon) on 33s. Goes everywhere I need it to (so far).

I'm curious about the extended brake lines you bought. Do you know that you need them, or is because your CJ needed them. I had the same thought when I upgraded from a CJ.
I have a Currie 4" lift coming tomorrow and the extended brake lines are due to the 4" lift. I used the link provided by Chris (Admin) for the Raybestos extended brake lines.
I appreciate the input, that's exactly what I need!
If it were me, I would do a 3-4” suspension lift with 32-33” tires. Save money on all those extra parts you would buy for 35s and direct the funds towards a tummy tuck. Between the lockers, 4:1 transfer case, and tummy tuck, you’ll have a rig that could go almost anywhere.

Really the only benefit to bigger tires is higher axle clearance and more sidewalk when aired down, like if you’re doing crazy bouldering. The rest of your rig can be raised with a suspension lift.

A Rubicon is already extremely capable in stock form. A few modest mods like listed above make it damn near unstoppable.

Also if you want to ditch the 16” wheels and to keep to Moab look, you can pick up JK 17” Moabs for super cheap because the market is flooded with JK takeoffs. I got a set of 5 with 32” BFGs for $200. You’d need spacers anyways to change the lug pattern so you could cover your issue of tire rub there too.
Great input!
I think 33's with a 4" lift looks great and proportional. I'm not stuck on the stock wheels.
The one thing I'm finding is that load range C is usually only available in 15" wheels. I've read until my eyes were cross-eyed on Load C, Load D and Load E. The Load C is less sidewall plys and supposedly the smoothest.
Which width is better 12.5 or 10.5? I'm sure theirs pro's and con's of each.

I think 33's on a 4" lift, tummy tuck, gear change (due to auto 42rle) is the right track.

Thank you both, much appreciated!
 
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Great input!
I think 33's with a 4" lift looks great and proportional. I'm not stuck on the stock wheels.
The one thing I'm finding is that load range C is usually only available in 15" wheels. I've read until my eyes were cross-eyed on Load C, Load D and Load E. The Load C is less sidewall plys and supposedly the smoothest.
Which width is better 12.5 or 10.5? I'm sure theirs pro's and con's of each.

I think 33's on a 4" lift, tummy tuck, gear change (due to auto 42rle) is the right track.

Thank you both, much appreciated!
If it were me I would go with the 10.5 width. Unless you need all of that tread when airing down, narrower tires work better as an all-purpose tire, IMO. I went from 33x12.5r15 BFG ATs to 255/70r17 BFG MTs (32x10”) and the handling /comfort improved tremendously. I do forest roads and open plains kind of wheeling so I have no need for anything big and bulky. Less width also means less weight and less tire for the engine to turn. Going down half an inch in diameter and 2.5” in width made an unbelievable difference in response. It also looks better without those fat tires sticking out of the side by 2”.

As for load ranges. That used to be the case until the JK came out with a 17” wheel. Before that you would only find that size wheel on a full size rig which would need a D/E range tire. However the JK is so light compared to it’s SUV counterparts that manufacturers realized they could make $$$ by providing a C range tire in a 17” wheel. This has been carried on to the JL wrangler, which actually come stock with 33” BFGs (285/70r17).

15” or 17” is up to you. Both are now a popular size in the Jeep world so prices should be pretty similar. 17” will definitely provide for comfort while sacrificing sidewall if you need that much (spoiler alert, I don’t need it 😉). 15” is vise versa. It all depends on your application and what you’ll use your Jeep for.
 
I have a Currie 4" lift coming tomorrow and the extended brake lines are due to the 4" lift. I used the link provided by Chris (Admin) for the Raybestos extended brake lines.
I appreciate the input, that's exactly what I need!

My point is slow down. Just like wheeling it first. Put your lift on, cycle your suspension, check your brake lines.
I've heard most don't need extended lines, or just move the brackets down, or use (cheaper) YJ lines.

All just suggestions, which is what you came looking for.
 
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Thanks to all who took the time to stop by and comment. It all helps me build the best jeep for my application.