Advice on 2.5" lift build

Irohk

Irohk

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St. Vincent and the Grenadines
I drive a 98 4.0L manual tj on 31"x10.5R15 with a 2" budget boost kit.
My father has some 2.5" RC springs and I'm looking to install them, I currently have some Rancho rs5000x (2-3 in) shocks on the way and have a few questions concerning a 2.5" lift.
Would I need a SYE/new driveshaft or can I can away with a transfer case drop, the jeep would be mainly daily driven with a small amount of trail driving. I had plans to do the SYE but I also want to regear to 4.10, so I'm wondering if a transfer case drop would work for what I use the jeep to do since I would rather spend the money on regearing.
I have done a bit of research on both regearing and the SYE, so I know that I can handle the SYE but regearing is out of the question for me. I plan to buy the revolution gear Dana30/Dana 35 4.10 regear kit with Koyo bearings (I've already found one on amazon).

I would appreciate some advice, so I don't run into any unnecessary problems.
 
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Irohk said:
I drive a 98 4.0L manual tj on 31"x10.5R15 with a 2" budget boost kit.
My father has some 2.5" RC springs and I'm looking to install them, I currently have some Rancho rs5000x (2-3 in) shocks on the way and have a few questions concerning a 2.5" lift.
Would I need a SYE/new driveshaft or can I can away with a transfer case drop, the jeep would be mainly daily driven with a small amount of trail driving. I had plans to do the SYE but I also want to regear to 4.10, so I'm wondering if a transfer case drop would work for what I use the jeep to do since I would rather spend the money on regearing.
I have done a bit of research on both regearing and the SYE, so I know that I can handle the SYE but regearing is out of the question for me. I plan to buy the revolution gear Dana30/Dana 35 4.10 regear kit with Koyo bearings (I've already found one on amazon).

I would appreciate some advice, so I don't run into any unnecessary problems.
Click to expand...
Your plan should work. You may not need a full transfer case drop and may be able to just add in some washers between the skid plate and the frame to drop it just enough to keep the vibes away. As you are aware though, the SYE and DC driveshaft with adjustable rear uppers would be the best way to go.
 
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The consensus seems to be that the Monroe 0”-2” lift shocks will work on 2.5” and maybe even 3”. The next size up needlessly shorten the up travel of the suspension. Cycling the suspension is recommended to set the proper height stops.
 
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Irohk said:
I drive a 98 4.0L manual tj on 31"x10.5R15 with a 2" budget boost kit.
My father has some 2.5" RC springs and I'm looking to install them, I currently have some Rancho rs5000x (2-3 in) shocks on the way and have a few questions concerning a 2.5" lift.
Would I need a SYE/new driveshaft or can I can away with a transfer case drop, the jeep would be mainly daily driven with a small amount of trail driving. I had plans to do the SYE but I also want to regear to 4.10, so I'm wondering if a transfer case drop would work for what I use the jeep to do since I would rather spend the money on regearing.
I have done a bit of research on both regearing and the SYE, so I know that I can handle the SYE but regearing is out of the question for me. I plan to buy the revolution gear Dana30/Dana 35 4.10 regear kit with Koyo bearings (I've already found one on amazon).

I would appreciate some advice, so I don't run into any unnecessary problems.
Click to expand...
I installed a 1 inch MML with my 2 inch lift and it smoothed it right out. No need to drop the TC
 
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imahnu said:
Your plan should work. You may not need a full transfer case drop and may be able to just add in some washers between the skid plate and the frame to drop it just enough to keep the vibes away. As you are aware though, the SYE and DC driveshaft with adjustable rear uppers would be the best way to go.
Click to expand...
Okay nice, yes I know the SYR and DC are the way to go. I have plans to do it in the future
 
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roverhi said:
The consensus seems to be that the Monroe 0”-2” lift shocks will work on 2.5” and maybe even 3”. The next size up needlessly shorten the up travel of the suspension. Cycling the suspension is recommended to set the proper height stops.
Click to expand...
Ohh, I assumed the 2-3 in would be ideal for 2.5” shocks
 
Irohk said:
Ohh, I assumed the 2-3 in would be ideal for 2.5” shocks
Click to expand...
To get detailed, it depends on the shocks compressed and extended lengths and the length of your shock mounts at ride height that determine what works best.

So if your shock length at ride height is say 15” and you’re getting a 8” travel shock then you’d want one that compresses to 11” and extends to 19” since that’ll give you an even split between up and down travel. If you want to get that detail you will have to measure your mounts once you install the RC springs. Then you can pick the shocks that give you closest to an even split.

Manufacturers give those ranges to make it quick and simple to know what shocks should work best for you. The downside of that way is that you might find you’ll have a less than ideal travel setup. Like 3” up and 5” down or vice versa.
 
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imahnu said:
To get detailed, it depends on the shocks compressed and extended lengths and the length of your shock mounts at ride height that determine what works best.

So if your shock length at ride height is say 15” and you’re getting a 8” travel shock then you’d want one that compresses to 11” and extends to 19” since that’ll give you an even split between up and down travel. If you want to get that detail you will have to measure your mounts once you install the RC springs. Then you can pick the shocks that give you closest to an even split.

Manufacturers give those ranges to make it quick and simple to know what shocks should work best for you. The downside of that way is that you might find you’ll have a less than ideal travel setup. Like 3” up and 5” down or vice versa.
Click to expand...
Okay I get you, I’ll look into that then. Cheers
 
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imahnu said:
To get detailed, it depends on the shocks compressed and extended lengths and the length of your shock mounts at ride height that determine what works best.

So if your shock length at ride height is say 15” and you’re getting a 8” travel shock then you’d want one that compresses to 11” and extends to 19” since that’ll give you an even split between up and down travel. If you want to get that detail you will have to measure your mounts once you install the RC springs. Then you can pick the shocks that give you closest to an even split.

Manufacturers give those ranges to make it quick and simple to know what shocks should work best for you. The downside of that way is that you might find you’ll have a less than ideal travel setup. Like 3” up and 5” down or vice versa.
Click to expand...
I have another question, would I need new sway bar links for the 2.5”?
 
Small update, I received all the parts I originally ordered. However I had to order some new springs because the ones I have are for a 4 door JK so they’ll give too much lift.

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