Seeking advice Broken Drive Shaft TJ 2000

[NB_Jeep]

I am looking for the best solution to a broken drive shaft. I have a 2000 Sahara with 33" tires 2.5" suspension but otherwise stock.

Options I am aware of (limited knowledge):
1) Junk yard replacement + Lowest cost - Expect that it broke because of drive shaft angle, and higher gear ratio due to tires.
2) SYE and longer drive shaft. + Cut the angle of the drive shaft down, stronger components. - Costly, does not address front drive shaft.
3) Lower the transfer case. + not so costly, reduces angle of both drive shafts, - lower ground clearance ?I got 4" of clearance less the spacers, only got 1.5" at axles.
4) Find Rubicon drive train parts. A garage offered this as a solution, then said that the electronics make this impractical. Is is really so difficult to retrofit? + Get lockers and better components. + Expensive but otherwise I am worried about putting money in a machine that has a weak axle etc.

What do you recommend?

[Russ Chung]

I got 4" of clearance less the spacers, only got 1.5" at axles.
https://www.dropbox.com/s/mm1m6dx5ki...47.02.jpg?dl=0

A few comments:
1. If you have 33" tires, and only 1.5" at the axles, you need to mount the tires and bolt the wheels to the axle and then measure again!!
2. The driveshaft angle did not cause the break; it was caused by hitting or high centering the driveshaft on a rock. Excessive driveshaft angle will cause the failure to occur at the u-joint and/or the ears at the end of the driveshaft.
3. If driveshaft angle is a concern and you want to reduce the chances of u-joint or ear failure, then go with option #2 (slip yoke eliminator), otherwise, just replace the driveshaft (option #1) and in the future, try to crawl over obstacles instead of powering over them.
4. From the look on your dog's face, are you sure he didn't chew it up??

[NB_Jeep]

Thanks for the advice. I agree that Lachley the Dog is a suspect. Worse that he posted it on his facebook page.

The hill I was climbing was less rocky, more steep than rocky. Slippery, then a diagonal outcropping of rocks.

What I meant was that increasing the tires by 3" gives me 1.5" more under the axles. With the 2.5" lift I got 1.5+2.5 or 4". The lift kit came with spacers to lower the pan under the transfer case. If the angles are reduced maybe I could lift the pan back +.5"

Found this page explaining the benefits of an SYE, sounds like this is a benefit when lifting. The video from Australia is interesting even though their product is not available. http://www.jeepforum.com/forum/f9/wh...nt-one-854790/

The Jeep has the other purpose of tow vehicle behind an RV. Trying to gain capability without giving my wife fits.

Is it possible to put a Rubicon rear end and transfer case in this Jeep? How involved is the wiring? Does it need a compressor?

[nwoods]

Bert, that's a great link and informative reference article from JeepForum. As a former Rubicon LJ owner, I never really had to deal with this, but it seems like perhaps you are suffering a bit of Analysis Paralysis? It seems like the cheapest solution is to go with a simple Double Cardan rear drive shaft and call it done.

Or...you can upgrade your drivetrain and implement a SYE and add a Double Cardan drive shaft.

Or.... you can REALLY upgrade your rig and install a Rubicon transfer case. If you do that, then you should also replace the front and rear axles, or at least the rear axles and then match the gearing up front. If you upgrade the rear axles, they don't need to be used Rubicon axles, but that might be the best bargin.

Rubicon's use a low pressure 6 to 8psi air compressor to engage the locker in the diff's. However, there are lots of other choices. I am a big proponent of selectable lockers, and that includes electronic lockers in addition to air lockers. Alternatively, there are "limited slip" style lockers that automatically engage if you have a bit of wheel spin. The most popular of these is called a TruTrac locker. I'm not a big fan of them. You don't always want to limit wheelspin, and there are sometimes some drivetrain issues on pavement with a TruTrac.

But the point is, if you snag a used set of Rubicon axles and transfer case, Yes, you will need a compressor, but they are very inexpensive, and are simply on/off switches you can add to the Dash. Daystar makes a switch panel that fits your dash perfectly:

[NB_Jeep]

Thanks Nathan,
With all of the help I am gaining an understanding of the options. Can't over analyze without info.

I didn't want to pay for a SYE and new shaft to drive a weak rear-end to break an axle.

I have spoken with a number of people that start with a simple Jeep then end up putting 10's of thousands into it. It will be great if I can find a donor set and be done without a more slippery slope.

At this stage of my life I hope to have the traction to craw though and try not to limp home.

Thanks to all for the advice

[nwoods]

I didn't want to pay for a SYE and new shaft to drive a weak rear-end to break an axle
At this stage of my life I hope to have the traction to craw though and try not to limp home.

Thanks to all for the advice

Probably best just to get the Double Cardan rear driveshaft until the Jeep budget exists for the upgraded drivetrain.... or until you find a sweet deal on a nice Rubicon LJ and save the hassle :-)

[Russ Chung]

If you switch from a rear driveshaft with single u-joints to one with a double cardan rear driveshaft, you will need to adjust the rear pinion angle. That means that you will need adjustable control arms. Here's some more reading material for you: http://4xshaft.com/JR7_TW_Driveshaft.pdf

[NB_Jeep]

Thanks Russ, This is a valuable article about the drive shaft and U joints. I heard a comment about the drive shaft calling it a fuse. It seems that my setup is likely to have caused undue stress on the drive shaft.

I am concerned about spending money on a SYE and new drive shaft driving a Dana 35 rear end. Should I be worried about the Dana 35 axles?
Another option was raised; try to find a Dana 44 rear end with a limited slip differential. What is the relative benefit between lockers and a limited slip differential?

[6spdYJ]

As far as the SYE with a Dana 35 to a Dana 44, as long as the Dana 44 comes from a TJ (non Rubicon) the u-joint will be the same Spicer 1310 and the axle will swap right in. The main difference between the two as far as the driveshaft goes is the 44's input yoke is one inch longer and thereby closer to the transfer case - meaning a 1" shorter driveshaft. If you plan to upgrade to the 44 in the future, just keep it in mind and buy your shaft according to the 44's length (and try to avoid full droop while still running the 35).

[dirtman13]

If it was me I would get a good drive shaft from one of these guys and call it good. No fun busting a drive shaft out in BFE. Both these sources are very knowledgeable and will help you make the best decision. I have used both and recommend both. I'm currently using some High Angle shafts front and rear. My front shaft on my CJ is from a Toyota truck.
http://www.4xshaft.com/
http://www.highangledriveline.com/

[NB_Jeep]

DONE: Stepped up to an SYE

Thank you for all of your help.

I brought the Jeep in to get a new drive shaft.
Good news, the rear end was Dana 44. Worth having a strong drive.
Bad news, the output shaft on the transfer case was cracked. Labor cost to fix.

So I had a Slip Yoke Eliminator installed. They were able to raise the transfer case as well.

I appreciate the forum. Glad to be back on the hills.