A comparison of building for 33s and 35s

[Irun]

Good idea, and good list!

I may of missed it, but throw in some type of swaybar disconnects for both, and RCV axles for 35's.

Regarding the skids: I would say NOT needed for 33's, and Yes to 35's.
Plates and Skids are important, especially sliders when in a decent sized rock garden, or in the "rocks." But the frequency or likelihood of a 33 in the rocks vs a 35 in the rocks is lower. (In rocks where skids are needed)


Also, consider noting intangible concepts such as: wear and tear between 33 & 35 and COG.

Swaybar added! The RCVs isn't something I'd say was a need, much like a 1350 u joint up front. They are both subjects that bring out differing opinions. Whereas, installing 1541H shafts in a Dana 35 and 4340 shafts in everything else gets no argument.

 

[Irun]

How am I supposed to convince my wife I need all these upgrades for 35's ? Can we add this to your list? LOL

My wife is way smarter than me. Don't ask for my help here. You're on your own!

 

[Irun]

I know some do not like them but to get the most out of either build you really have to run a body lift. So with that in mind for 33s I would run 3 inch springs. Shock choice may be a bit more challenging but that one inch less in height gives you better control arm angles, less angle on the steering linkage making for less effort in maintaining drivability. Then put your effort into raising the belly and gas tank to their fullest extent which I think would offer better performance off road compared to doing a 4 inch suspension and no body.

I agree. Without a BL you can't maximize the belly height. This is especially true if you have the Rubicon, with a much larger 241OR. Thoughts from others here on whether the BL is essential?

 

[jjvw]

I agree. Without a BL you can't maximize the belly height. This is especially true if you have the Rubicon, with a much larger 241OR. Thoughts from others here on whether the BL is essential?

A body lift is essential for raising the gas tank. And a good raised belly still needs some tub clearancing for the 231 with a body lift. And I'm nearly sure that some of the PSC steering gears need a body lift to fit under the grill.

Introduce cutting and welding into the types of mods being done, and the body lift let's you do even more.

 

[Irun]

I don’t think either build needs a new front driveshaft. I’m not sure how much more optimal the build would be with one. If it works, and it should, it works.

I've personally seen a front shaft separated. However, that same Jeep lost a front spring. This sounds consistent with the comment from @jjvw about down travel. I can remove it, but would like others to chime in.

 

[Irun]

A body lift is essential for raising the gas tank. And a good raised belly still needs some tub clearancing for the 231 with a body lift. And I'm nearly sure that some of the PSC steering gears need a body lift to fit under the grill.

I left the BL out, but included the GTS, mainly with the thought you could install a Savvy skid with or without a BL. This however means you're not getting the most clearance. Personally, there are way more reasons to install a BL than not. I'm thinking it should just be a yes, yes?

 

[Sancho]

I've personally seen a front shaft separated. However, that same Jeep lost a front spring. This sounds consistent with the comment from @jjvw about down travel. I can remove it, but would like others to chime in.

You can go down a deep rabbit hole chasing an optimal build.

Personally, speaking for 33's, I wouldn't categorize front drive shaft as optimal preformance, but classify it as optimal protection.



Tho, you did define your list to account for underside protection. I feel you can have a trail worthy rig without it.

 

[jjvw]

I left the BL out, but included the GTS, mainly with the thought you could install a Savvy skid with or without a BL. This however means you're not getting the most clearance. Personally, there are way more reasons to install a BL than not. I'm thinking it should just be a yes, yes?

The 03-06 factory GTS can also be cut and raised up an inch after a body lift. It's free and more should do it. Which means more should do a body lift!

 

[jjvw]

You can go down a deep rabbit hole chasing an optimal build.

Personally, speaking for 33's, I wouldn't categorize front drive shaft as optimal preformance, but classify it as optimal protection.

Tho, you did define your list to account for underside protection.

It's a matter of optimal performance. We try to not use the drive shafts as a sliding surface the way we can with control arms. But we do like the drive shaft to last a long time, which means appropriate spline engagement following a spring lift.

 

[Sancho]

It's a matter of optimal performance. We try to not use the drive shafts as a sliding surface the way we can with control arms. But we do like the drive shaft to last a long time, which means appropriate spline engagement following a spring lift.

I get the idea, and support it as a mod, just not essential to a trail worthy rig. I am seeing a lot of scope creep here, and instinctually try to slow it down. (Admittedly,not my place to do do)


I'm just hung up on definitions here. I see a difference between performance and protection.

Though separate concepts, they are correllated, and both needed for optimal builds.

 

[toximus]

You can get a 1/4" wall driveshaft made and beat it up but suffer from parasitic loss, or you can get a normal 0.120" wall shaft and build your rig to try and keep it out of the rocks.

There's trade offs to everything.

 

[jjvw]

I get the idea, and support it as a mod, just not essential to a trail worthy rig. I am seeing a lot of scope creep here, and instinctually try to slow it down. (Admittedly,not my place to do do)


I'm just hung up on definitions here. I see a difference between performance and protection.

Though separate concepts, they are correllated, and both needed for optimal builds.

Maybe read the opening post a third time. This isn't about cutting corners and building something on the cheap just because you can get away with it. Nor is it an all out, leave nothing on the table build discussion. The idea is to build something well for these two tire sizes in a way that is mostly accessible to anyone with ambition and can work a wrench. That includes suggesting that a driveshaft be an appropriate length.

 

[Irun]

Maybe read the opening post a third time. This isn't about cutting corners and building something on the cheap just because you can get away with it. Nor is it an all out, leave nothing on the table build discussion. The idea is to build something well for these two tire sizes in a way that is mostly accessible to anyone with ambition and can work a wrench. That includes suggesting that a driveshaft be an appropriate length.

Many of us have learned the hard way that cutting corners will come back to bite you. We should view this list as the consensus of folks that have experience to share with others. As @toximus said, you can cut corners, but there are tradeoffs. This list is meant for those that are truly serious about building a rig that will not disappoint or leave you stranded.

 

[Sancho]

Maybe read the opening post a third time. This isn't about cutting corners and building something on the cheap just because you can get away with it. Nor is it an all out, leave nothing on the table build discussion. The idea is to build something well for these two tire sizes in a way that is mostly accessible to anyone with ambition and can work a wrench. That includes suggesting that a driveshaft be an appropriate length.

Go ahead, scope creep the list Into a $20k vehicle mod just for 33's.

 

[jjvw]

Go ahead, scope creep the list Into a $20k vehicle mod just for 33's.

By suggesting a properly sized driveshaft and encouraging a free raised gas tank skid. Got it.

 

[Wildman]

IMO a body lift is a must.
Can run a MM lift to help with driveshaft angles before you can afford the SYE. But if you do the body lift then the cable shifter becomes necessary. I hated crawling under mine to either shift it to 2WD or reconnect the linkage once it separated.

While I can agree with most of your list I also know that you can build a capable rig with a lot less. But it won't be optimal for on and off road.

 

[Irun]

By suggesting a properly sized driveshaft and encouraging a free raised gas tank skid. Got it.

You and @TheBoogieman are children of the Devil. We're going to need a Jeep exorcist here!

 

[freedom_in_4low]

It depends on the amount of down travel combined with a few other things. I am aware of a few fairly standard 35" builds with about 5.5" of down from ride height where the stock front driveshaft had very little spline engagement at full shock extension. Most are not checking for this the same way most are not checking the rear driveshaft for bind at full droop.

Are these midarm builds? The arc of 16" shortarms pulls backward more quickly vs down travel than the arc of a 41"ish driveshaft. I agree with needing to look at the front shaft because I had to replace mine - not from being too short though, it was from being too long. The splines bottomed out before the shocks were at full extension and the weight of the front axle plus a couple of inches worth of spring rate was resting on the transfer case. I now have a TW shaft with XC splines that rides just slightly extended so it has room to compress.


This is with 11" ranchos 5 up/6 down and a high pinion, which does exacerbate the arc discrepancy.

 

[jjvw]

Are these midarm builds? The arc of 16" shortarms pulls backward more quickly vs down travel than the arc of a 41"ish driveshaft. I agree with needing to look at the front shaft because I had to replace mine - not from being too short though, it was from being too long. The splines bottomed out before the shocks were at full extension and the weight of the front axle plus a couple of inches worth of spring rate was resting on the transfer case. I now have a TW shaft with XC splines that rides just slightly extended so it has room to compress.


This is with 11" ranchos 5 up/6 down and a high pinion, which does exacerbate the arc discrepancy.

All I know is that it exists and there are several factors that play into the stock front driveshaft being too short after a 4" spring lift. Beyond that, I don't care much about mathing it out when it is easy enough to check on the actual rig.

At the end of the day, it is what it is. And this is one of those things that should be paid some attention to when building a rig.

 

[toximus]

The power steering cooler is a must from my perspective. However, the caveat would be it's really only necessary if you're doing a lot of slow crawling.

Once you start getting into the land of high flow pumps a cooler is needed all the time.