Putting the new axels in this weekend

[Bryan C.]

I have noticed before that running a Jeep on the rack without the front wheels turning will cause some weird noises to come from the transfer case. Best to do this test with the transfer case engaged in 4wd. Another good thing to add is whether the suspension was at full droop, if so try again with the vehicle at right height, like with jackstands under both front and rear axles with the wheels off the ground.

I have also noted that 8.25" axles will humm at freeways speeds. Lower gear ratios will make this condition worse. I noticed it first when I changed ratios from stock to 4.56. The noise was what I would call a humm or drone sound, it got pretty loud. It went away when I swapped in my D44.

 

[Skipper51]

Did you check the ujoints in the rear driveshaft? I dont see an SYE in your sig, do you have one? I've never used a stethescope on my jeep before, but if the driveshaft was vibrating, you could say it was coming from the rear corner panel, or your driver side headlight and be just as right.

That is exactly how I feel about it. It could be anything.

 

[Skipper51]

I would pull the rear DS and try it again . Hey Skip can you post pics of the rear pinion to DS from the side? maybe you have some axle wrap issues?

Love to Jon..DO you want it on the ground or on the lift?

 

[blondejoncherokee]

On the ground as it sits

 

[Skipper51]

I have noticed before that running a Jeep on the rack without the front wheels turning will cause some weird noises to come from the transfer case. Best to do this test with the transfer case engaged in 4wd. Another good thing to add is whether the suspension was at full droop, if so try again with the vehicle at right height, like with jackstands under both front and rear axles with the wheels off the ground.

I have also noted that 8.25" axles will humm at freeways speeds. Lower gear ratios will make this condition worse. I noticed it first when I changed ratios from stock to 4.56. The noise was what I would call a humm or drone sound, it got pretty loud. It went away when I swapped in my D44.

When it was on the lift I did have it in H4 and the suspension was in full drop.

This is way more than a hum Bryan it is a grinding sound. The new axels have a (or what appears to be a) steeper angle than the 7% I had on the old axels. This could be making more pressure on the TC bearing causing it to make that grinding sound. Just thinking.

 

[Skipper51]

On the ground as it sits

I do that first thing in the morning Jon.

 

[Skipper51]

I have noticed before that running a Jeep on the rack without the front wheels turning will cause some weird noises to come from the transfer case. Best to do this test with the transfer case engaged in 4wd. Another good thing to add is whether the suspension was at full droop, if so try again with the vehicle at right height, like with jackstands under both front and rear axles with the wheels off the ground.

I have also noted that 8.25" axles will humm at freeways speeds. Lower gear ratios will make this condition worse. I noticed it first when I changed ratios from stock to 4.56. The noise was what I would call a humm or drone sound, it got pretty loud. It went away when I swapped in my D44.

No SYE and there has been a slight vibration but not a lot ever since I did the3.5" lift and maybe a little more when I went to 4.5".

 

[GordoSmasho]

I'll bet that bearing was on its way out. I've had out of balance driveshafts kill pinion bearings. The same can be true for the output bearings. You need to do a sye. Even a hack n tap. Sye. Sounds like the new axle spring pads were burned in at an angle to work with an sye not a standard slip yoke. That will put extra stress on that bearing and on ujoints.

Also 60mph at fulldroop is not a good idea. That will put a hell of a lot of stress on ujoints and slip joints in te driveshafts. Way outside normal operating angels and ranges.

Next time put the vehicle on jack stands under the axles. Get all four tires off the ground. Then the suspension will be at normal ride height and try it.

 

[Skipper51]

I'll bet that bearing was on its way out. I've had out of balance driveshafts kill pinion bearings. The same can be true for the output bearings. You need to do a sye. Even a hack n tap. Sye. Sounds like the new axle spring pads were burned in at an angle to work with an sye not a standard slip yoke. That will put extra stress on that bearing and on ujoints.

Also 60mph at fulldroop is not a good idea. That will put a hell of a lot of stress on ujoints and slip joints in te driveshafts. Way outside normal operating angels and ranges.

Next time put the vehicle on jack stands under the axles. Get all four tires off the ground. Then the suspension will be at normal ride height and try it.

Yeah Gordon the more I think about it the more I am thinking that it is the out put bearing.

So guys what is a good inexpensive SYE kit and is using a front drive shaft a good way to go? I will only be running 33" tires but I am locked now.

 

[GordoSmasho]

I have a hnt like the one from ironrockoffroad. You can also order there's with a new shaft. I just went to the jy and found one in decent shape.

 

[XJensen]

Yeah Gordon the more I think about it the more I am thinking that it is the out put bearing.

So guys what is a good inexpensive SYE kit and is using a front drive shaft a good way to go? I will only be running 33" tires but I am locked now.

Oh, no SYE?? That needs to be next on the list and might just be the cause of all the issues.

I would go with a full SYE if you can swing it, I know you just flipped some bills for those axles though. Either way I have a spare front shaft I carry for a spare, duh. You can use it if you like, maybe keep it if I get a new tcase soon.

I should be swapping my case out in the Fall and it has a full sye. Doesn't sound like you can wait.

 

[blondejoncherokee]

PNP asks around 30$-40$ for a shaft. the most expensive part of a HNT is the yoke, the yokes are about 93$ just by themselves. Honestly, serious off road or some other vendors has a full SYE for like around 160$ or around there , do that , and spend 40$ on a front shaft(or get one from a member) . The new rear output in the SYE is beefy. More than likely the Junkyard front shaft will bolt right and be fine, maybe replace the pinion U joint with a new spicer 1310. I wouldnt F with the CV or CV joints. Just find the best looking shaft in the yard and replace the pinion U joint.


pics of your setup will help. With a stock rear shaft you might just have your angles out of whack. honestly, you might not need a SYE, you might just need some Degree shims to angle the pinion back up or back down.

stock: rear pinion angle= T case output angle. (think parallel )

SYE: rear pinion angle = 1-3* below DS angle.

I have a feeling you are gonna post a pic with a rear pinion pointed up, like a SYE setup, and you will will need to shim back down to get the DS angle in line.



If you can, post DS angle, pinion angle, and tcase U joint at the output shaft angle.


My money is not on the Tcase , its on the DS angles and possibly a few bad U joints.

 

[Skipper51]

Oh, no SYE?? That needs to be next on the list and might just be the cause of all the issues.

I would go with a full SYE if you can swing it, I know you just flipped some bills for those axles though. Either way I have a spare front shaft I carry for a spare, duh. You can use it if you like, maybe keep it if I get a new tcase soon.

I should be swapping my case out in the Fall and it has a full sye. Doesn't sound like you can wait.

Thank you for the offer but I need to move on this right away to get ready for Reno.

Yeah, the SYE was on the list to do but I was hoping that it would wait a little long before it needed to be done. :banghead:

So Rugged Ridge has a SYE for $170 and PnP has drive shafts for $70 for a two piece and $40 for a regular. XJ front DS a reg or two piece? Anyway
for about $170 I could do HnT with DS and for $250 I could do the SYE with DS. $80 difference and $50 has always been my tipping point to just do the upgrade.

 

[GordoSmasho]

I will second Jon on this actually. Doing a full sye replaces the bad bearing as well. Two birds? One...

Xj front ds is a one piece $40

 

[Skipper51]

Ordered a SYE based on gut feeling, and the input you all gave me, should be here 5/7. Now I need a front drive shaft to get it running. Anyone know of one for sale????

 

[GordoSmasho]

Picknpull.

 

[831_xj]

Which sye did you get?
Some driveshafts might be too short

XJ 87/88 2.5 Automatic 27.950 53003912
XJ 89/93 2.5 Automatic 27.970 53005540
XJ 89/01 2.5 Manual 25.310 53005541
XJ 89/01 4.0 Automatic 30.660 53005542
XJ 89/01 4.0 Manual 29.250 53005543
XJ 89/00 4.0 Manual 27.080 Export 53005544
XJ 89/00 4.0 Automatic 28.620 Export 53005545
XJ 87/88 4.0 Automatic Export 53005260 *
XJ 95/01 Diesel 27.640 Export 52098208

ZJ 1993 4.0 Automatic 30.530 52098341
ZJ 93/95 5.2 Automatic 32.870 w/o CV 53008427
ZJ 94/95 5.2 A500 30.625 w/o CV 52087805
ZJ 94/95 4.0 A500 w/o CV 52098790
ZJ 93/96 4.0 Manual 52098344
ZJ 93/96 4.0, 5.2 31.875 w/ 231, 242 52087805
ZJ 93/95 4.0 Manual 30.000 w/231 52088090
ZJ 93/96 5.2 33.000 w/ 231 53008427
ZJ 96/98 5.2, 5.9 31.250 w/ 249 & Model 30 52098379
ZJ 1996 5.2 Automatic 32.875 w/ 249 & Model 30 52098501
ZJ 96/98 4.0 33.000 w/ 242 52098707
ZJ 96/97 4.0 Automatic 31.250 52098850
ZJ 1996 5.2 Automatic 30.750 w/ 249 & Model 30 52099246
ZJ 96/98 4.0 33.500 w/ 249 52099260

Those are collapsed lengths

 

[XJensen]

Ordered a SYE based on gut feeling, and the input you all gave me, should be here 5/7. Now I need a front drive shaft to get it running. Anyone know of one for sale????

Come Take My spare

 

[831_xj]

If need be I have a 33.5" collapsed Ds you can have. It was too long for my teraflex sye and 8.25 with an auto. It needs ujoints as I took them for spares. Once you get your sye installed you want to measure yoke to yoke. I have a front XJ ds on mine now from an auto. It's a tad shorter than I'd like it but works just fine.

 

[blondejoncherokee]

Realisitally you don't want to pay money for a shaft until you install the SYE. then take measurements. or, grab a 31" shaft from somewhere and that should be close enough.


Remember if your angles are out of whack , the SYE may not fix it, you may still have to shim it to get the pinion angle right.

Also, if your current U joints are bad, that could be it. Also, U joints can be bad on a new DS from the junkyard and it may seem like the problem is still there.

Did you pop the U joint caps on your current rear shaft to make sure there is no journalling on the trunions. Like I said before, if the pinion is pointed way upwards then you just have to shim it back down. Or, if its pointed up, but under the DS angle you can do a SYE. either way a SYE wont hurt anything, but it ale might not fix it .