Okay everyone, I am in the middle of installing a 4 inch suspension lift on my XJ. I am being told that I will need to purchase a slip yoke eliminator and a CV style drive shaft. I read on here that I could use a slip yoke out of a YJ or a ZJ instead and that would eliminate any problems that I might have with my lift kit. I was just looking for some input, what is a better way to go? Obviously it would be cheeper for me to get a slip yoke from a zj or yj, but would it be the "better" solution? Any help would be great!
-
Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.
What would be better a YJ slip yoke or eliminator kit.
- Thread starter outracing
- Start date
VAhasnoWAVES
NAXJA Forum User
- Location
- Lake City, Mi
using the slip yoke from a YJ or ZJ? ive never heard of such a thing.
regardless, it is the slip yoke that you want to eliminate. SYE or H&T.
regardless, it is the slip yoke that you want to eliminate. SYE or H&T.
RCP Phx
NAXJA Forum User
- Location
- Phoenix,Az
YJ's and late XJ's use a yoke that has more clearance to eliminate binding at extreme angles.
But with that said it does nothing to eliminate vibes,thats what the sye kit does.
OP,the late model t-cases are more problematic!
But with that said it does nothing to eliminate vibes,thats what the sye kit does.
OP,the late model t-cases are more problematic!
So, for my 99 it sounds like the SYE kit with the CV style driveshaft is the way to go? I see that there are alot of different makes. Any input on what would be a good one? I use my to push a snow plow in the winter, so I would need one that would stand up to the abuse of plowing...
Also, what is H&T?
Also, what is H&T?
VAhasnoWAVES
NAXJA Forum User
- Location
- Lake City, Mi
explain?
hack and tap. basically you cut the splined output shaft, drill and tap the center of it. slip a splined yoke over whats left of the shaft, and bolt it into place. then bolt in a double cardan shaft.
Kevin108
NAXJA Forum User
- Location
- Virginia Beach, VA
The 96 and newer transfer cases have a different tail cone on the output shaft that leaves them more likely to suffer vibrations. The upside is, their output shaft is completely sealed so you can remove the rear driveshaft and drive on the front axle without losing fluid.
Grab the Iron Rock Offroad H&T SYE kit from Dirtbound Offroad. Use coupon code
for $10 off, making the total $89. http://www.dirtboundoffroad.com/featured/slip-yoke-eliminator-hd-yoke-style-by-dirtbound-offroad/Grab a stock front XJ driveshaft for around $30 from your local junkyard. Also check CraigsList to look for bargains. Make sure the driveshaft isn't the older "stick in a can." Typically an 87-01 rigs have what you want but Jeep liked to mix and match parts. I've seen this old-style craptastic CV shaft on rigs as late as 89. The driveshaft you want will be identical to what you have up front now on your 99. It will have 3 u-joints and a crazy Spicer ball and socket arrangement. These are actually called double-cardan driveshafts although many still refer to them as CV shafts.
My write-up on installing my SYE can be found at http://www.jeepforum.com/forum/f177/kevin108s-2000-xj-build-867428/index17.html#post12482199
Last edited:
xcm
NAXJA Forum User
- Location
- Southern Oregon
stock style (slip yoke, hence the 'slip', slides in and out on a splined output shaft of the transfer case... if you break a driveshaft, it slides right out of the transfer case.
you need to eliminate this, with a 'slip yoke eliminator' kit, which bolts the yoke to the output shaft, eliminating the slip HERE, you move it onto the driveshaft with a cv-style driveshaft...
if this all confuses you... buy a kit. i used the Advance adapters, but it requires internal transfer case work, a H&T requires you to tap cut and tap the output shaft on the vehicle.
you need to eliminate this, with a 'slip yoke eliminator' kit, which bolts the yoke to the output shaft, eliminating the slip HERE, you move it onto the driveshaft with a cv-style driveshaft...
if this all confuses you... buy a kit. i used the Advance adapters, but it requires internal transfer case work, a H&T requires you to tap cut and tap the output shaft on the vehicle.
Porch951
NAXJA Forum User
- Location
- Albuquerque, NM
My two cents:
The hack-n-taps are a pain in the ass to install and it seems like the vast majority of them end up with vibrations sooner or later.
An "HD" SYE costs just a little bit more and takes just a little more time. You'll never have problems with it. If you look on youtube for "HD SYE Install" you'll see exactly what gets done.
Check out the Performance Offroad Centers (PORC) HD SYE. I just threw my IRO piece of garbage SYE in the trash and installed my PORC. My only regret is ever buying from IRO....
The hack-n-taps are a pain in the ass to install and it seems like the vast majority of them end up with vibrations sooner or later.
An "HD" SYE costs just a little bit more and takes just a little more time. You'll never have problems with it. If you look on youtube for "HD SYE Install" you'll see exactly what gets done.
Check out the Performance Offroad Centers (PORC) HD SYE. I just threw my IRO piece of garbage SYE in the trash and installed my PORC. My only regret is ever buying from IRO....
Kevin108
NAXJA Forum User
- Location
- Virginia Beach, VA
The factory driveshaft slides in and out on the output shaft coming out of the transfer case. With a slip yoke eliminator, the Y-shaped yoke at the end of the drivehshaft is physically attached to the output shaft on the transfer case. The double-cardan driveshaft is built to lengthen and extend within itself. These variations are necessary to allow for proper suspension travel and compression.
The point of adding a slip yoke eliminator is so you can run a double-cardan driveshaft which still functions well at more extreme angles and is less likely to induce driveline vibrations.
Why do I need a new driveshaft? The one that I have won't work? I guess I was just thinking that a SYE kit was for the rear drive shaft only. Does the kit do the front and rear? Or do I just need to do the front only?
- Location
- Southern Maryland
The stock rear driveshaft is fixed-length. One end is attached to the axle, and the other end is attached to the transfer case (the body). Since the stock rear shaft fixed length, it cannot compress or lengthen when the body moves up and down relative to the axle. Instead it uses a "slip yoke" design, where one end of the shaft moves in and out of the transfer case, thereby allowing the effective distance to change dynamically.
When you convert to a fixed yoke, you are eliminating the slip-yoke (hence the name, SYE), and you will need a driveshaft that can compress and expand. The front driveshaft from an XJ is already setup this way, and has the correct style of u-joints for our vehicles. So most people usually just buy another front driveshaft and stick it on the rear when they install an SYE. This isn't always feasible since there are a lot of variations in length based on various factors.
When you convert to a fixed yoke, you are eliminating the slip-yoke (hence the name, SYE), and you will need a driveshaft that can compress and expand. The front driveshaft from an XJ is already setup this way, and has the correct style of u-joints for our vehicles. So most people usually just buy another front driveshaft and stick it on the rear when they install an SYE. This isn't always feasible since there are a lot of variations in length based on various factors.
- Location
- Southern Maryland
get a tape measure and see
Kevin108
NAXJA Forum User
- Location
- Virginia Beach, VA
What I've read indicates that a stock front XJ driveshaft will work with the H&T SYE with lifts up to 5". I've read (but do not know for sure) that the Grand Cherokee front driveshafts are the same design but longer, which would work for lifts over 5". The front driveshafts are strong enough for intense wheeling. I think they'll handle most anything the vehicle itself is capable of.
For a few bucks more I would get an actual SYE and not just a HnT.
http://www.jeeperz-creeperz.com/tra...nators-np231-slip-yoke-eliminator-p-6456.html
http://www.jeeperz-creeperz.com/tra...nators-np231-slip-yoke-eliminator-p-6456.html
- Location
- Southern Maryland
The driveshafts connect to the transfer case, which is bolted to the transmission. Since different transmissions are different dimensions, the transfer case will have a physically different offset depending on the transmission in use, and as a result the front driveshafts are different lengths depending on the transmission in the donor vehicle. This is true for every vehicle that was offered with multiple powertrain options (including the ZJ).
For example, an AX5 manual trans is physically shorter than the AX15, which is shorter than the AW4. Since the transfer case is bolted to the transmission, it will be further forward on an AX5 than the others, and as a result the front driveshaft will be shorter than one from the others too.
Really you have to measure and then find a driveshaft that fits. For most people with an AW4 the front driveshaft is close enough to be used on the rear after an SYE conversion, but not always. Different types of SYE conversions will have different size issues, as will installation choices, year of the XJ involved, etc.
For example, an AX5 manual trans is physically shorter than the AX15, which is shorter than the AW4. Since the transfer case is bolted to the transmission, it will be further forward on an AX5 than the others, and as a result the front driveshaft will be shorter than one from the others too.
Really you have to measure and then find a driveshaft that fits. For most people with an AW4 the front driveshaft is close enough to be used on the rear after an SYE conversion, but not always. Different types of SYE conversions will have different size issues, as will installation choices, year of the XJ involved, etc.
Last edited:
Kevin108
NAXJA Forum User
- Location
- Virginia Beach, VA
On top of that, you can cut off or leave on a substantial amount of the output shaft to make a given driveshaft be a perfect fit for your application.
Everyone, thank you very much for all your input. I have alot of options available to me, I did by a SYE kit, I didn't really want to try that hack and tap option. I am still very new to this sport, but am jumping in with both feet. I used a tape measure and did get a front drive shaft from another 1999 jeep cherokee with an auto and a np231 transfer case, which is the same set up as mine. I have not however found the time to get it (along with some other lift components) installed. I am very much looking forward to getting everything in and figuring out how to get rid of my "Death Wobble" that I am now experiencing... :doh:
OutkastBoss
NAXJA Forum User
- Location
- Saint louis
glad to see your well on your way to doing the better of the two options.
jeeps are funny they all seem to be different for instance the late models seem to have a horrible reputation for getting vibes easier but mine was at 4" for about a year with no SYE and had no vibes whatsoever. I did my sye as peace of mind and longer u joint life (due to better angles).
I used the I.R.O. Hnt with their inspected and repainted stock front D.S. (and their tap kit) and am very happy with it. I.M.O. it sounds alot harder than it is. You don't even have to get the hole drilled perfect since the splines line it up and the weight of the bolt head is negligable
The only ones I've seen fail (so far) was the flange style and they got bent maybe? They became unbalanced.
The flange style (like I.R.O.) I've heard of peoples coming loose but felt like it was maybe user error.. Personally I used loc tite and torqued the bolt pretty good and checked it a week later and then every few months when I check torque on all my suspension and grease everything with a zerk fitting I'll check it as well.
that being said if I wouldve had the cash I wouldve done a full hd and it would be stronger.
I'm only going to run 33's and don't beat the rig or do big rocks.
I also really like having my spare driveshafts fit on both ends.
Porch how did your I.R.O. Fail?
jeeps are funny they all seem to be different for instance the late models seem to have a horrible reputation for getting vibes easier but mine was at 4" for about a year with no SYE and had no vibes whatsoever. I did my sye as peace of mind and longer u joint life (due to better angles).
I used the I.R.O. Hnt with their inspected and repainted stock front D.S. (and their tap kit) and am very happy with it. I.M.O. it sounds alot harder than it is. You don't even have to get the hole drilled perfect since the splines line it up and the weight of the bolt head is negligable
The only ones I've seen fail (so far) was the flange style and they got bent maybe? They became unbalanced.
The flange style (like I.R.O.) I've heard of peoples coming loose but felt like it was maybe user error.. Personally I used loc tite and torqued the bolt pretty good and checked it a week later and then every few months when I check torque on all my suspension and grease everything with a zerk fitting I'll check it as well.
that being said if I wouldve had the cash I wouldve done a full hd and it would be stronger.
I'm only going to run 33's and don't beat the rig or do big rocks.
I also really like having my spare driveshafts fit on both ends.
Porch how did your I.R.O. Fail?
