SYE and non-cv yoke / driveshaft

xXDavidCXx

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I feel like this may elicit the angry TJ gods, but...

Can I install a SYE and use a new and longer standard non-cv rear drive shaft?

I'm sure the question is then, why not get a double cardan DS? Because I don't want the extra costs of the supporting suspension mods to tilt the pinion angle, and I'm not lifting the jeep.

Why would I want to do this? Because I may need to inspect the inside of the T-case and I'd hate to take it apart and replace any broken items and not put in a SYE at the same time.

If the angle gets better with a SYE, does this negate some of the benefits of a double cardan DS?
 
I feel like this may elicit the angry TJ gods, but...

Can I install a SYE and use a new and longer standard non-cv rear drive shaft?

I'm sure the question is then, why not get a double cardan DS? Because I don't want the extra costs of the supporting suspension mods to tilt the pinion angle, and I'm not lifting the jeep.

Why would I want to do this? Because I may need to inspect the inside of the T-case and I'd hate to take it apart and replace any broken items and not put in a SYE at the same time.

If the angle gets better with a SYE, does this negate some of the benefits of a double cardan DS?

Can’t be a standard longer driveshaft. Has to have a slip joint on the shaft like a Rubicon
 
If you get equal and opposite angles between the driveshaft and T-case and axle pinion , don't exceed the working angle of the U-joints , and as mentioned by GPK03X include a slip joint in the shaft it will work.
 
I actually would prefer a standard driveshaft if the angles are allowable. Sounds like yours are. Just need to order the non-CV yoke when you do it.

The SYE would be a solid way to beef up the transfer case while allowing for better angles on a stock Jeep. There are no downsides or in other words, besides angles, there is no upside to a double cardan shaft (‘CV’).
 
For the most part, the only reason to do a SYE is to facilitate a double cardan shaft. The bonus is that you get a fixed output yoke on the transfer case which I like better as it is a more solid way of attaching things. Another bonus is that you shorten the output of the transfer case, thereby lengthening the shaft, and reducing angles, but this change in angle is subtle, the extra length only reduced the drive shaft angle by maybe 4 degrees. These bonus changes are great but the reason for the sye is to facilitate the double cardan shaft. The double cardan shaft requires that you rotate the pinion up of course but that is actually where you get a lot of the angle reduction. You can see how the angle reduction progresses with each step in the video embedded on the page below.

Then there's the matter of almost every SYE coming with a 1310 CV style yoke. This yoke won't work with a non-cv shaft. I'm pretty sure Advance Adapters sells the SYE with no yoke and then you can get the non-cv yoke separately but this will also require that you change the seal in the SYE housing. It can be a bit more of a challenge to get an SYE setup for a non-cv shaft.

If you are wanting to run a non-cv shaft, I'd recommend that you forego the SYE and just run a stock type shaft. I don't think that the small advantages of doing the sye without the CV shaft are substantial enough to justify the expense and the labor. Where I'd make an exception, where I'd recommend a SYE and a non-cv shaft, is here: If a guy has a bent or broken output shaft and has to replace the output shaft of the transfer case anyway but has a stock height (no lift) Jeep. In this scenario the guy has to get a new output shaft and tear apart the t-case anyway so he might as well make the upgrade. Then, when in comes to the shaft there's no reason to switch the the CV and I like the simplicity of the single joint at each end of the shaft better, less things to wear out.

If you really want to do the SYE without the CV shaft, do it, but in my opinion you should either just save yourself a bunch of money and run the stock type shaft or spend the extra money to do the SYE and cv shaft.

The video on this page shows demonstrates how the angle changes progressively change with each step of the SYE, CV, and Control Arm process.

https://4xshaft.com/blogs/general-t...-eliminator-installation-purpose-and-benefits
 
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Where I'd make an exception, where I'd recommend a SYE and a non-cv shaft, is here: If a guy has a bent or broken output shaft and has to replace the output shaft of the transfer case anyway but has a stock height (no lift) Jeep. In this scenario the guy has to get a new output shaft and tear apart the t-case anyway so he might as well make the upgrade. Then, when in comes to the shaft there's no reason to switch the the CV and I like the simplicity of the single joint at each end of the shaft better, less things to wear out.

I feel like this is nearly the scenario I’m trying I get across except I don't have a broken shaft, I'm just replacing it with a SYE.

Then there's the matter of almost every SYE coming with a 1310 CV style yoke. This yoke won't work with a non-cv shaft. I'm pretty sure Advance Adapters sells the SYE with no yoke and then you can get the non-cv yoke separately but this will also require that you change the seal in the SYE housing. It can be a bit more of a challenge to get an SYE setup for a non-cv shaft.
I was eying the JB 1350 no-cv option.

https://www.jbconversions.com/products/sye/np231j_short_sye.php
 
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I feel like this may elicit the angry TJ gods, but...

Can I install a SYE and use a new and longer standard non-cv rear drive shaft?

I'm sure the question is then, why not get a double cardan DS? Because I don't want the extra costs of the supporting suspension mods to tilt the pinion angle, and I'm not lifting the jeep.

Why would I want to do this? Because I may need to inspect the inside of the T-case and I'd hate to take it apart and replace any broken items and not put in a SYE at the same time.

If the angle gets better with a SYE, does this negate some of the benefits of a double cardan DS?

Your profile states a 2 inch front leveling kit and a UCF TC skid. If you have tucked the drivetrain any, you should just go ahead with the SS SYE and DC driveshaft. Probably can get by with just adjustable upper control arms.
 
Your profile states a 2 inch front leveling kit and a UCF TC skid. If you have tucked the drivetrain any, you should just go ahead with the SS SYE and DC driveshaft. Probably can get by with just adjustable upper control arms.

I'm using a one-inch spacer on the transfer skid since I haven't tucked/body lifted yet.

If I did end up tucking, and I have the kit ready to go, only purchasing the adjustable upper arms reduces my costs quite a bit.

Trying not to spend $2500 just to put a SYE in.
 
I'm using a one-inch spacer on the transfer skid since I haven't tucked/body lifted yet.

If I did end up tucking, and I have the kit ready to go, only purchasing the adjustable upper arms reduces my costs quite a bit.

Trying not to spend $2500 just to put a SYE in.

I have a 2 inch lift with the UCF extra clearance skid. Also have the ROKMEN 1/2 inch body lift. I used the LOPRO trans mount so the body lift wasn’t really needed. I installed the JB SS SYE and TOM WOODS CV driveshaft. With the small lift and mild tuck the pinion doesn’t have to be rotated that much. I used ROKMEN UPPER CONTROL ARMS AND JEEP works great. You may need a track bar bracket and I’m not sure if the Lopro mount is available for your trans. Some people don’t like the Lopro because it can transmit vibes. You will love the clearance under your Jeep. JUST EMPTY EVERY POCKET!
 
Yes,the knowledge Jerry brings to the forum is very helpful. Shawn , you answered the phone quickly at your business and helped me with my driveshaft needs.Thanks to the both of you.
 
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