Does the transfer case move at all while driving?

Alatex

TJ Enthusiast
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Installed AA SYE and TW CV shaft along with a Barnes 4WD bolt on skid plate with their transmission mount. I’m chasing some mild vibes that start at 70mph and I’ve noticed that my Tcase is very close to my skid plate. Maybe an 1/8” or 1/4” max between the bottom of the case and the skid. Doesn’t the tcase have any play at all while driving? Could it be causing my vibes?
 
Installed AA SYE and TW CV shaft along with a Barnes 4WD bolt on skid plate with their transmission mount. I’m chasing some mild vibes that start at 70mph and I’ve noticed that my Tcase is very close to my skid plate. Maybe an 1/8” or 1/4” max between the bottom of the case and the skid. Doesn’t the tcase have any play at all while driving? Could it be causing my vibes?

if you look at your manual transmission shifter as you drive, the way that moves around is indicative of how much the engine/trans/case move around. They are supported by rubber mounts, after all.

1/4" would surprise me a little, but I can definitely see it making contact with only 1/8" of clearance.
 
if you look at your manual transmission shifter as you drive, the way that moves around is indicative of how much the engine/trans/case move around. They are supported by rubber mounts, after all.

1/4" would surprise me a little, but I can definitely see it making contact with only 1/8" of clearance.
I’m considering throwing some washers on to raise it up just a hair
 
Try putting the stock mount back in. Also check your motor mounts for too much play.
 
Installed AA SYE and TW CV shaft along with a Barnes 4WD bolt on skid plate with their transmission mount. I’m chasing some mild vibes that start at 70mph and I’ve noticed that my Tcase is very close to my skid plate. Maybe an 1/8” or 1/4” max between the bottom of the case and the skid. Doesn’t the tcase have any play at all while driving? Could it be causing my vibes?
I highly doubt that is what is causing your vibes.

Maybe you could tell us more about the vibes. What happens as you increase speed to 80mph? Are they continuous vibes or oscillating? Do they get faster and faster or just a constant vibe? Have you detached the front driveshaft and gone for a drive?
 
I highly doubt that is what is causing your vibes.

Maybe you could tell us more about the vibes. What happens as you increase speed to 80mph? Are they continuous vibes or oscillating? Do they get faster and faster or just a constant vibe? Have you detached the front driveshaft and gone for a drive?
It’s 100% not the front shaft and once you get to around 65-70 it’s steady, doesn’t change with speed increase.
 
It’s 100% not the front shaft and once you get to around 65-70 it’s steady, doesn’t change with speed increase.
A driveline vibe will increase with speed, so if your analysis is correct I'd look outside of the driveline. Wish I could help more. I hate chasin down vibes.
 
A driveline vibe will increase with speed, so if your analysis is correct I'd look outside of the driveline. Wish I could help more. I hate chasin down vibes.
Yeah I’m gonna go through and torque of the control arms again, it’s just frustrating to have done an upgrade by getting ride of the tcase drop and “correcting” the driveline angles only to have vibrations coming from somewhere. I’ll find the culprit eventually
 
Yeah I’m gonna go through and torque of the control arms again, it’s just frustrating to have done an upgrade by getting ride of the tcase drop and “correcting” the driveline angles only to have vibrations coming from somewhere. I’ll find the culprit eventually
How much lift do you have? What is your rear pinion angle? Do you have a DC shaft?
 
How much lift do you have? What is your rear pinion angle? Do you have a DC shaft?
4” lift, I believe I’m at 16 for the shaft and 15 for the pinion, yes it’s a cv shaft
 
4” lift, I believe I’m at 16 for the shaft and 15 for the pinion, yes it’s a cv shaft
You could always try every angle from +-2* difference.
 
it’s just frustrating to have done an upgrade by getting ride of the tcase drop and “correcting” the driveline angles only to have vibrations coming from somewhere.
Is the skid plate also a Tummy tuck?
If you got rid of a drop down spacer, and raised the TC; you just moved it quite a bit.
 
Could not having an angled track bar bracket and a stock rear track bar cause vibrations?
Yes. If you rotated your pinion up it could be either binding the track bar or causing the track bar to rub on the gas tank skid. Mine rubbed the skid which caused vibes until I put an angled bracket on.
 
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Could not having an angled track bar bracket and a stock rear track bar cause vibrations?
At 4” lift and stock TB your rear axle is going to be shifted hard to the passenger side. Ideally you want an adjustable trackbar to center the axle. Without it your pinion will be shifted toward the passenger. That is frowned upon with a Ford 8.8 which is similar. I don’t know if it it’s enough shift to cause vibes. Sorry. Either way you DO need an adjustable TB.