Rear CV driveshaft-No SYE needed?

[pantherchams]

I was looking around at hack n tap kits for my np242 and came across this rear shaft on ebay.


It looks like it is made just like a front shaft except for the piece that slides into the Tcase.

Has anyone used something like this to get rid of vibes? It seems like such a simple solution, and I have had a good experience with Adam's, but I have never seen it before.

thoughts? Think it would get rid of vibes on a 3.5" lift and last?

Thanks
Ben

 

[256offroad]

that works... but for that amount of money get a hack n tap and use a front driveshaft and call it done.

 

[pantherchams]

that works... but for that amount of money get a hack n tap and use a front driveshaft and call it done.

Is there an advantage to the hack n tap over this other than running the same DS front and rear (which is pretty cool)? I don't feel that comfortable hacking the output shaft off and drilling a hole in the middle of it.....

I mean, if it wasnt going to be spinning a million miles an hour, fine, but..



Ben

 

[winkosmosis]

Well the advantage of a SYE or HnT is that the slip yoke is a stupid design that has inherent binding. I don't think this mod would get rid of vibrations, so what's the point?

 

[pantherchams]

I don't think this mod would get rid of vibrations, so what's the point?

Well that was my question. Obviously there is no point if it doesn't act the same as an SYE and get rid of vibes/the need for a tcase drop.

 

[casm]

Well that was my question. Obviously there is no point if it doesn't act the same as an SYE and get rid of vibes/the need for a tcase drop.

Unless I've missed something here, by it does not by definition act the same as an SYE - it's not eliminating the slip yoke. Sure, it adds a CV joint, but it's not fixed in place at the yoke on the output shaft of the transfer case.

Looking at the second photo in the set (the one where you can see the rear driveshaft running to the diff), it appears as though the pinion has been angled upwards. Assuming this to be the case, the combination of this driveshaft and the change in pinion angle may remove driveline vibes.

Having said that: I ran an NP242 with a stock rear driveshaft and no SYE at 3" of lift. I did install 4-degree axle shims to get the pinion pointed up, and had no rear driveline vibes with that configuration (still don't, as it happens - the shims are still in there even now at 4.5" and with an SYE).

My gut feeling is that while this may lessen the need for an SYE, it doesn't necessarily eliminate it - and since it doesn't change the pinion angle in and of itself, it may still leave you susceptible to vibes. YMMV, but I'd tend to think that degree shims would be a better first line of attack if you don't want to get involved with an SYE. They're also going to be substantially cheaper - $300 for that driveshaft? Yikes.

 

[Blaine B.]

Right that seems like an "alternative" for NP242 transfer cases where a true SYE is not available (only Hack-N-Taps with the NP242)

Doesn't seem like a bad idea though although an SYE or Hack-N-Tap with true SYE slip-yoke driveshaft is better.

 

[Blaine B.]

Also seems to be like ALOT of extra weight being supported by that rear bearing in the transfer case....which is why an SYE is also a good choice as well, especially when your stock driveshaft starts pulling out further and there isn't an even balance on that bearing anymore. This just adds more weight to that.

 

[casm]

Right that seems like an "alternative" for NP242 transfer cases where a true SYE is not available (only Hack-N-Taps with the NP242)

No, there are full tailshaft conversions available for the NP242. I've been running the Tom Woods late-design 242 one for a few years now and love it; an early model kit is also available. IIRC, Advance Adapters also offered one as well as a couple of other manufacturers.

 

[Doctor94R]

I had the rear shaft converted to a CV, at the place that did my gearing, exactly as the ebay ad shows. My Jeep was 4.5" and had no vibrations.

It cost no where near what the ebay ad wants to have the stock shaft converted.

 

[ehall]

This design keeps the slip yoke, the driveshaft does not have a slip joint. Basically they took a regular driveshaft and put a double-cardan joint at one end. Is it the right length for the lift? Dunno but there is an awful lot of exposed slip yoke in the close-up picture. Almost certainly won't be the right length for your lift. If you want to try one do the math and have a driveshaft made. I also suspect that the rear axle will need to be shimmed to point at the transfer case for the double-cardan to work properly, which is another cost. Frankly it would be simpler and easier to keep the stock driveshaft, unless you have vibes at which point you can do the right fix for the same price as what it would cost to do this half-fix.

 

[Blaine B.]

Really, I learn something new everyday. Is the 242 kit fairly new? In the past I always remember hearing the only downfall to the 242 was that a full SYE kit was not available besides the hack-n-tap.

 

[casm]

Really, I learn something new everyday. Is the 242 kit fairly new? In the past I always remember hearing the only downfall to the 242 was that a full SYE kit was not available besides the hack-n-tap.

No idea as to how long they've been doing them for, but I've had it on there for somewhere between 3 and 4 years now. If I had to guess, I'd say that they cropped up somewhere in the 2005 timeframe - I seem to recall that they came out with the full tailshaft conversion either just before or just after I got the current XJ in early 2005.

 

[Blaine B.]

Earlier than I would have guessed but I suppose still "late" if you take in to account the amount of time that an SYE for the 231 has been available.

 

[RCP Phx]

Spobi,AA doesnt make a kit for the 242!

 

[casm]

Spobi,AA doesnt make a kit for the 242!

IIRC, Advance Adapters also offered

Note the use of 'If I Remember Correctly' and "offered" - i.e., the past tense of 'offers'.

If I'm wrong on AA having offered one, I'm wrong - and that's fine, which is why I phrased my recollection conditionally. But SPOBI? No. At no point did I say that they currently offer a 242 tailshaft kit, because they don't.

 

[pantherchams]

Lots of good info, thanks everyone! I have never seen those tom woods np242 kits before.

Sounds like I will pass on this and find a more legit solution.

Thanks!

Ben