Lowered transfer case

[grayson20]

Hey guys I've only been on here a short time and yalls advice, knowledge is insane! I bout this 97 tj as something to tool around in, I only gave a 5k for it knowing it had been wrecked and rebuilt. It has a 4.0 and an ax15 5 speed. I'm looking to swap the 35s for 31s.....I dont mind the 2.5in coil lift, I noticed I ha e a little vibration during acceleration, I see it has some shims to lower the transfer case, also see pics, the 4wd linkage is messed up...best way to fix it? Cable? Vibration? Try shimming some more?

 

[Rickyd]

It looks like one end of your tcase linkage zbar popped out of its socket.

A cable shifter is supposed to be the best solution.you can also just get a drop plate for the body side zbar pivot so it is horizontal again.

Best case you get an sye and new rear drivshaft so the tcase drop can be removed though.

Speaking of the rear driveshaft,is there something going on with the ujoint at the axle? I see some shiny spots in the pic that kinda look like it is coming apart.

 

[grayson20]

It looks like one end of your tcase linkage zbar popped out of its socket.

A cable shifter is supposed to be the best solution.you can also just get a drop plate for the body side zbar pivot so it is horizontal again.

Best case you get an sye and new rear drivshaft so the tcase drop can be removed though.

Speaking of the rear driveshaft,is there something going on with the ujoint at the axle? I see some shiny spots in the pic that kinda look like it is coming apart.

Are the slip yoke kits a pretty easy install? Is there a kit that's highly recommended over another?....my first thought was a bad u joint and still might be but at first glance all the joints appeared tight. That shinny spot caught my eye as well but after rotating shaft both sides were shiny and looked like a newer joint maybe...cup seemed normal. If a few washers would effect the vibrations I would work on the 4x4 linkage, if not I will just do the sye and raise the transfer the transfer case back up.. thanks!

 

[Rickyd]

The rear axle looks to be at the wrong angle as well.that will cause vibrations.
Here's a picture showing how the angles should be for the different types of driveshaft. The lower arms are likely too short(edit)

 

[grayson20]

The rear axle looks to be at the wrong angle as well.that will cause vibrations.
Here's a picture showing how the angles should be for the different types of driveshaft. The lower arms are likely too long

The rear axle looks to be at the wrong angle as well.that will cause vibrations.
Here's a picture showing how the angles should be for the different types of driveshaft. The lower arms are likely too long
View attachment 584024

Hmmmmm the rear arms are adjustable but appear to be all the way in. Maybe wrong arms? Your thinking my pinion is angled like the bottom illustration but I have a drive line like the top one?

 

[flyinfish]

Definitely the wrong driveline angle to keep the u-joints in phase. I'd get the 31's on and then get your pinion angle set right. Doing 35's properly isn't cheap and will require a double carden drive shaft and preferably a SYE. A shift cable as Rickyd mentioned is a good upgrade no matter where you land.

BTW, the access hole cut into the side of frame is priceless. It appears to have been the previous owner's remedy for accessing a spinning nutsert.

 

[TheBoogieman]

I'd remove the t-case drop, install a MML, and adjust the linkage.

 

[Rickyd]

Hmmmmm the rear arms are adjustable but appear to be all the way in. Maybe wrong arms? Your thinking my pinion is angled like the bottom illustration but I have a drive line like the top one?

The pinion looks like it needs to go down. Adjusting the lower arms longer will do that

 

[Tob]

Judging by control arm angle and tire clearance, it looks like you might have more than 2.5” lift.

The vibrations are very likely coming from the rear driveshaft. Refer to the diagram Ricky posted. Yes, you have the driveshaft of the top but the angle of the bottom. Shorten the rear upper control arms if they are adjustable as well, and/or lengthen the lower control arms until the pinion angle and transfer case output angle are closer. It may take some fine tuning to dial out the vibrations.

If the driveshaft angle is still too steep, a MML may help. No need to remove the transfer case drop spacers unless you want more ground clearance for off-roading.

The shift linkage is susceptible to disconnecting. You should be able to reconnect it. Alternatively if you want to spend money, a cable shifter works very nicely compared to the factory linkage and will not come apart.

 

[grayson20]

Definitely the wrong driveline angle to keep the u-joints in phase. I'd get the 31's on and then get your pinion angle set right. Doing 35's properly isn't cheap and will require a double carden drive shaft and preferably a SYE. A shift cable as Rickyd mentioned is a good upgrade no matter where you land.

BTW, the access hole cut into the side of frame is priceless. It appears to have been the previous owner's remedy for accessing a spinning nutsert.

Yeah I noticed the hole for nut lol.

Judging by control arm angle and tire clearance, it looks like you might have more than 2.5” lift.

The vibrations are very likely coming from the rear driveshaft. Refer to the diagram Ricky posted. Yes, you have the driveshaft of the top but the angle of the bottom. Shorten the rear upper control arms if they are adjustable as well, and/or lengthen the lower control arms until the pinion angle and transfer case output angle are closer. It may take some fine tuning to dial out the vibrations.

If the driveshaft angle is still too steep, a MML may help. No need to remove the transfer case drop spacers unless you want more ground clearance for off-roading.

The shift linkage is susceptible to disconnecting. You should be able to reconnect it. Alternatively if you want to spend money, a cable shifter works very nicely compared to the factory linkage and will not come apart.

So do i need to at least get a drop plate? I couldn't get that back in the socket at that angle

 

[Rickyd]

Yeah I noticed the hole for nut lol.


So do i need to at least get a drop plate? I couldn't get that back in the socket at that angle

Something like this is in my jeep. It shifts like stock

https://www.extremeterrain.com/rugged-ridge-drop-bracket-yj-tj-1830505.html

 

[LONGJP2]

Vibration? Try shimming some more?

Have you determined whether the vibe is coming from the front or rear?

 

[grayson20]

Have you determined whether the vibe is coming from the front or rear?

I am pretty certain rear.......it takes of smooth and once I go from second to third I have bad vibration upon acceleration from then on out.....I am going to adjust pinion angle but and maybe inspect u joints a little better. It just started doing this within the last 2 or 3 times I've driven. It's always vibrated some on acceleration but not to this extent....were u thinking motor mounts?

 

[LONGJP2]

....were u thinking motor mounts?

It could be the front driveshaft.
Disconnect it to confirm it's the rear.

 

[grayson20]

Update.....swapped for a set of 5 33 in Patagonias. New rear yoke and rear u joints. Adjusted pinion angle.......vibration gone.

 

[TheBoogieman]

Update.....swapped for a set of 5 33 in Patagonias.

View attachment 586140

I know a guy on here that really likes those tires.

 

[John Cooper]

I know a guy on here that really likes those tires.

And a few that don't

 

[Apparition]

And a few that don't

 

[DeltaNu1142]

So do i need to at least get a drop plate?

For what it's worth... I put in a cable shifter, set the ends to the recommended length, and the transfer case shifts like butter. It's worth the extra $$ to know I won't have to screw with it again.

 

[TheBoogieman]

For what it's worth... I put in a cable shifter, set the ends to the recommended length, and the transfer case shifts like butter. It's worth the extra $$ to know I won't have to screw with it again.

Why do all of mine shift fine (greased linkage)? The same mechanism is used on many Jeeps. yet TJ owners complain the most. DON'T tell me all TJ owners are Dems. I shift in and out of 4WD 30+ times daily when using my Jeep for many hours on my driving job. If it was an issue, It would have been the first mod I did. I got $500 knocked off the price of my wife's WJ because it got stuck in 4WD on the test drive. Bought it, greased the linkage and it shifts like butta.