JBA Y-Link Extension

krisP said:

been having some driveline vibe issues .... since i still have original ujoints with 85000 miles on them they will be replaced first...much overdue anyways....if that doesnt help ill do some washer adjustments. Just when you think youve got it all figured out haha :emotions34:

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She just wants some more lovin' :icon_lol:

no need to unbolt the extension from the diff right ? i can just unbolt the extension from the link , roll the jeep until the pinion is where i want it and then readjust the washers from there ?

i need the pinion on the rear diff to go down if that makes a difference

krisP said:

no need to unbolt the extension from the diff right ? i can just unbolt the extension from the link , roll the jeep until the pinion is where i want it and then readjust the washers from there ?

i need the pinion on the rear diff to go down if that makes a difference

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That will work , most times thats what everyone needs is the front down more
Good luck

tommudd said:

That will work , most times thats what everyone needs is the front down more
Good luck

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just couldnt get it to where i was happy, took it out all together. would rather have stress on uca then bad driveline vibes.

a shorter uca and it would work great. Looks like a new custom 4 link is in store

krisP said:

just couldnt get it to where i was happy, took it out all together. would rather have stress on uca then bad driveline vibes.

a shorter uca and it would work great. Looks like a new custom 4 link is in store

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Really couldn't get it where you wanted?

tommudd said:

Really couldn't get it where you wanted?

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it seemed to have the pinion at a decent angle the link itself would be at an agle that wouldnt allow it to bolt on. Limited by the boomerang/ ball joint, almost as if it would need to be a few inches shorter. Im probably doing something wrong or not doing something right. When i have more time after my clinical rotations for school ill play around with it some more.

jba uca, clevis lift, larger tires and leveling the rear will all be done within the next month so after thats all squared away ill come back to this

tommudd said:

For just a moment forget the washers
Remove them completely
NOW sit the rear diff up according to the pictures I posted
Then see how many washer it will take to achieve that ( washers between both brackets)
Going from someone else picture is a guess that his and your's are exactly the same
Don't get hung up on how many washers are shown in the instructions, set yours up the way it should, each maybe a little different
Of course flat on the gront or sit up level on jackstands with out the rear diff hanging down

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Hey Tom need some help here. I'm trying to get my pinion angle right but it's just not working out. It seems like the axle needs to be moved back a bit. I have about 3.5 inches of lift in the back.

Here's what happens when i set the pinion a bit more level...



The extension ends up IN FRONT OF the bracket...which can't be. The only way I can hook this damn thing up is by angling the pinion up.

I took the extension out all together now. The pinion angle is about the same with or without the bracket.

PS - rolling my Jeep in gear doesn't affect the pinion angle. Is it because I have an open dif? I ended up just using a jack on the pinion and differential to raise/lower the angle.

Thanks in advance for the help. All other opinions welcome, too!

OK now with that picture you have me confused :shrug::icon_lol:
Let me go look at one of mine in the AM and figure out what you have done for sure :gr_grin:

tommudd said:

OK now with that picture you have me confused :shrug::icon_lol:
Let me go look at one of mine in the AM and figure out what you have done for sure :gr_grin:

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Thanks. Appreciate any input. Since the lift I've had some vibes at higher torques around 2200-3k RPMs. Just don't want to be doing damage to my pinion. Tomorrow I'll grab a picture of the rear drive shaft from end to end so you can see the angle I'm working with.

Just use your floor jack under the pinion to rotate the pinion up, use a block of wood and Jack behind the axle up under the lower coil seat. Here's a picture of the bracket.

Like mentioned above, don't waste the time trying to duplicate what you see on another rig. No 2 rigs will be the same. I've never put one of the extensions on, so I can't comment on the specifics. What I do is use my jack to set and hold the pinion angle, then adjust my arms/bracket/whatever.

Sent from my Motorola 2950 Special Edition 3w.

the_dealer said:

Just use your floor jack under the pinion to rotate the pinion up, use a block of wood and Jack behind the axle up under the lower coil seat. Here's a picture of the bracket.

You must be registered for see images attach

Like mentioned above, don't waste the time trying to duplicate what you see on another rig. No 2 rigs will be the same. I've never put one of the extensions on, so I can't comment on the specifics. What I do is use my jack to set and hold the pinion angle, then adjust my arms/bracket/whatever.

Sent from my Motorola 2950 Special Edition 3w.

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The problem is my pinion is pointing upward while doing that. I can set and install the extension or the bracket by itself no problem. It's how the pinion is set that bothers me.

The picture above simply shows what the whole situation looks like if I lower my pinion a few degrees to match the output of the transfer case.

Here are my pinion angles...





It's like my LCA's are too short or something. I've just never heard of anyone running into these problems like I am.

How many washers did you try ?
You're not going to get it exactly flat on both ends to match ( or I never could )
But try it with the JBA bracket right against the diff bracket to see where you sit

tommudd said:

How many washers did you try ?
You're not going to get it exactly flat on both ends to match ( or I never could )
But try it with the JBA bracket right against the diff bracket to see where you sit

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It's about the same. That's where i was prior to removing it. Same angle, same vibes.

There's really no room to add washers due to the fact that it just moves the JBA bracket away from the Y link, causing fitment to be more difficult.

Just imagine. The picture that I showed you with the JBA bracket sitting in front of the Y link is where everything sits when everything is level. I have to tilt the pinion up enough to actually fit the bracket. Leading to a radically tilted pinion as pictured.

Could be possible one or both of your lower arm axle or "frame" brackets are tweaked. A **** hair off will make a huge difference. Have you tried rocking the rig side to side to let it go neutral?

Sent from my Motorola 2950 Special Edition 3w.

the_dealer said:

Could be possible one or both of your lower arm axle or "frame" brackets are tweaked. A **** hair off will make a huge difference. Have you tried rocking the rig side to side to let it go neutral?

Sent from my Motorola 2950 Special Edition 3w.

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Possible I suppose...but it's not like one side fits and one doesn't. The thing is tracking straight.

The axle seems like it's about half an inch too far forward.

Doesn't adding washers to this thing tilt the pinion UP more???

I'm thinking about taking the sawzall to the Y link to make it possible to fit the JBA bracket IN FRONT OF the Y link.

I got one of these to install with my lift next weekend, after reading through this thread twice I really hope I don't have a lot of trouble lol. Also does anyone have suggestions for specific brands or versions of u joints I'm going to replace mine when I lift and axle swap because who knows when they were changed if ever.

dude1116 said:

It's about the same. That's where i was prior to removing it. Same angle, same vibes.

There's really no room to add washers due to the fact that it just moves the JBA bracket away from the Y link, causing fitment to be more difficult.

Just imagine. The picture that I showed you with the JBA bracket sitting in front of the Y link is where everything sits when everything is level. I have to tilt the pinion up enough to actually fit the bracket. Leading to a radically tilted pinion as pictured.

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This is the exact same problem i ran into a month ago installing this. Tried every combo of washers possible. No matter what the pinion angle would cause nasty vibes. Took it off….buying bolt on 4 link…problem solved

krisP said:

This is the exact same problem i ran into a month ago installing this. Tried every combo of washers possible. No matter what the pinion angle would cause nasty vibes. Took it off….buying bolt on 4 link…problem solved

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We've installed quite a number of them here and never really had any issues at all. Not sure why some are having problems.

At what amount of lift is this bracket piece necessary?