Rear Driveshaft issue.. ( i think )

So back in November of last year, or maybe the year before... I put a RE 3.5 Super-flex lift kit on my jeep. It's a '94 and it netted around 5" of actual lift. As soon as I started moving I felt the vibs, so I dropped the TC about an inch, and all went well.

This past weekend, I upgraded all the brake parts... new rotors / pads, drums / shoes / etc. Everything was fine.

Today on the way to work i noticed some knocking sounds in the back. When I accelerate it is quiet, but as soon as I let off the gas I hear it. It is quicker when going faster, and slower when moving slow.

So what did I do over the weekend to cause this problem to show it's ugly face again?

I know the best thing to do is a SYE, but I haven't gotten around to it, but it looks as though this may speed that process up... looking at the RE1801 Hack-n-tap right now, as it seems to be the only one that is for NP242's (which I have). Even though it doesn't list the NP242. is there any better methods for the NP242?

i would start with checking the work you did over the weekend on the rear brakes.

I'm strongly considering switching out my 242 to a 231...You can get one for around $100 and then put an SYE kit in it for under $300 for just the SYE and around $500 for the SYE and driveshaft. There is just no support for the 242. If you are going to get lockers at some point the money you save by being able to run an autolocker up front will pay for itself.

98XJLimitedNateWV said:

I'm strongly considering switching out my 242 to a 231...You can get one for around $100 and then put an SYE kit in it for under $300 for just the SYE and around $500 for the SYE and driveshaft. There is just no support for the 242. If you are going to get lockers at some point the money you save by being able to run an autolocker up front will pay for itself.

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Selectable Lockers are ok though right? I've been looking at the ARB Air lockers a lot lately, esp since my dad has them and they are awesome, plus the benefit of having OBA.

98XJLimitedNateWV said:

I'm strongly considering switching out my 242 to a 231...You can get one for around $100 and then put an SYE kit in it for under $300 for just the SYE and around $500 for the SYE and driveshaft. There is just no support for the 242. If you are going to get lockers at some point the money you save by being able to run an autolocker up front will pay for itself.

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Run Go-Jeeps hack and tap... it is more or less what Tom Wood's offers for the 231. The aluminum case will explode before a stock tail shaft will fail so there is not need for a "heavy duty" output shaft. Read the 242 sye threads... I can count 5 cases of people reporting breaking something on their 242. Way more 231 failures are documented. The aftermarket support may not be as great... (boo no 4:1 kits) but for the majority this tcase works perfectly fine for someone that DD's their junk. If this was a pure trail rig then yes I would argue to swap in a 231 if they need the crawl ratio.

Diff gears are your friend!

There is no issue running a locker with a 242 it just defeats the purpose of it... I wouldn't toss a lunch box in the front anyway because my XJ sees more road time then off road. I do have intentions of putting a lunch box in the rear and allowing the use of full time to still be usable (I currently have a factory trash-lock), when time and $ permits I will be tossing an OX up front.

Tenny said:

Selectable Lockers are ok though right? I've been looking at the ARB Air lockers a lot lately, esp since my dad has them and they are awesome, plus the benefit of having OBA.

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yes, but that was my point. They are alot more expensive. An ARB is like $800 for just the locker then you still need a compressor. A Lockright is about $300...

And I was definitely not saying that there is anything wrong with the 242, I like it. There is just no aftermarket for it. The reason you hear about more 231 failures is because there are so many more 231s out there.

J-Roc said:

There is no issue running a locker with a 242 it just defeats the purpose of it... I wouldn't toss a lunch box in the front anyway because my XJ sees more road time then off road.

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Well the issue is you can't use the full time 4wd with a lunchbox and a 242. The lunchboxes are invisible up front in 2wd...

Ahh I figured the issue out.

The bolts on the rear driver wheel were not tight... Thankfully I checked that before driving home. I had a co-worker go out with me during our lunch break, and I immediately noticed one wasn't tight, and sure enough one of us forgot to torque all the bolts down.


J-Roc, is this the link you are talking about: http://www.go.jeep-xj.info/HowtoSYEconversion.htm

that would be the one!

lilkuff said:

why cant you use a lunchbox and fulltime?

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one of the experts will have to give the specifics here, but its because of the way the full time 4wd works. the locker and that don't jive together.

so you cant use it at all or just on the street?

if you have a 242 you need a locker that can be completely disengaged to run fulltime 4wd.

The 242 allows the driveshafts to spin at diffferent speeds, which allows you to use it safely on pavement. If you have a lunchbox locker in there its going to be on constantly, so you will not be able to use the full time 4wd on the street. If not having fulltime 4wd isn't a big deal its not a problem, but as someone said earlier it sorta defeats the purpose.

An ARB is like $800 for just the locker then you still need a compressor. A Lockright is about $300...

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Look at an OX locker then. http://www.oconeeoffroad.com/servlet/the-3918/Have-the-control-at/Detail

my .02

lance

Actually, you can use an autolocker in the front of a 242 in full-time. I do, during the winter, though I have a limited slip in the back and have even heard of them being used with ARB(selectables) in the back. Its like driving around a front wheel drive car with traction control, just point and shoot, the rear follows. It wouldn't work if I have auto-lockers front and rear, possible, you would just have to learn how to drive, IE let off the gas around corners. Kind of like when you have dual lockers and 231 in 4wd in the snow, when you turn on the gas, you'll most likely go straight.


Anything is possible and doable, you just need to realize what you are driving and learn how to drive it. Remember boys and girls, you ain't driving your momma's sedan anymore.

I don't see a problem running a lunch box in the rear with a np242 in full time. I have a factory limited slip so when it engages how is it any different then running an auto locker? It isn't folks :yelclap:

Best setup IMO selectable front, auto rear... personal opinion but I'd rather be pushed then pulled.