lift problem.

[hunna]

I did half of my rusty's 3" lift yesterday, the back end is so high now, that the rear drive shaft like binds and makes noises, it kind of looks like the drive shafts about to fall out of the tranny.

Do you think its cause the fronts not done yet or do you think I need shims for the rear end, a tc drop or something else.

i still have my stock tires on to, would my bigger tires help correct the drive shaft angle.

I read somewhere that stock height is like 17” from the center of the hub, mine measured like 22”+ after the rear lift.

i got that from the center of my rim to the bottom of my rear mud thing.

89 sport 2 door 5 speed.

 

[JeepXJ93]

Deffinatly part of the reason is b/c the front isnt done yet....i had the same problem but at the same time, when i talked to rusty's they said after it settles see if the vibes go away and then in the worste case you can go ahead and do the t/c drop kit. Good luck.

 

[hunna]

right i think i'll finish the front and see how it is then, then get what i need after that.

 

[BigBlk XJ]

Deffinatly part of the reason is b/c the front isnt done yet....i had the same problem but at the same time, when i talked to rusty's they said after it settles see if the vibes go away and then in the worste case you can go ahead and do the t/c drop kit. Good luck.

ok honestly . think about it!!! how the hell is lifting the front gonna change anything with your REAR driveshaft??? seriously.. if u dont believe me.. go jack up the front up with a floor jack.. does it change anything? nope.. cause the only thing thats gonna change that is moving your rear axle up down/back forth, anyways.. get a TC DROP, just do it.. take out the bolts, go to the hardware store and get 1" longer bolts, then get soem steel or at WORST washers, and put 1" of them in there all the way around, simple, problem solved.. hell on my 8" of lift i just ground the hell outta my driveshaft till it spun free.. no problems yet!

 

[hunna]

i just ground the hell outta my driveshaft till it spun free.. no problems yet!

thats what afriend told me to do. i didn't think the front was going to help either.

 

[hunna]

what about shimming the rear how much would i need like rusty's has 3* and 6* shimms.

 

[JeepXJ93]

OK...i was just stating what rusty's suggested.

 

[hunna]

OK...i was just stating what rusty's suggested.

no thats cool i need all the help i can get.

thanks .

 

[Island XJ]

shimming will only help change the angle that the differential pinion is facing. you need the angle on the pinion to be the same as the angle on the transfer case so that the ujoints will turn in phase and not give you vibes. Adding an angled shim to a diff that is already in the right position will only give you vibes. if you added longer shackles you will need an angled shim to make up for the angle introduced by the shackles. also, if you installed a SYE and a DC (CV) driveshaft you need angled shims to point the pinion at the Tcase. If you did not do either of these, then you do not need angled shims, they will only screw things up. Try the drop case for now and then see about getting a SYE and longer shaft in the future.

 

[hunna]

so how much should i drop it like 1".

 

[dink]

i just did a Rusty's 3" on my 91 XJ and the TC drop did the trick. I bought one from Rusty's (consists of 1" lnger bolts and two pcs of machined alum spacers). Clears 31's nicely and no vibration yet.

 

[hunna]

i'll try the tc drop,

my backs is like 5" over stock, how much did you get from your kit.

 

[dink]

About 5" on the rear to start with, but it settled down to about 4" within the first couple of days. The springs are much stiffer than stock ones.

 

[hunna]

The springs are much stiffer than stock ones.

ya i had a friend about 240 pounds stand on my bumper and the back hardly even moved down.

 

[MaXJohnson]

... the rear drive shaft like binds and makes noises, it kind of looks like the drive shafts about to fall out of the tranny.

"binds and makes noise"
"drive shafts about to fall out"

There's all the clues you need.

Your transfercase output yoke (slip yoke) doesn't have enough throat clearance for the u-joint angles that you're running, hence the noise and binding. Your drive shaft is not long enough to accomodate 5" of lift, hence the appearance that it's going to fall out. It probably will the next time you hit a large bump or dip at speed. I wouldn't consider driving it like that.

A transfercase drop will help, but proabably not enough. A longer drive shaft and high clearance yoke would do better. The best bet is a SYE, including new drive shaft and appropriate change in pinion angle.

 

[hunna]

i guess i should start saving for a sye and shaft.

is there any shaft that i could pull from junk yard that would be the right size.

 

[Island XJ]

i guess i should start saving for a sye and shaft.
is there any shaft that i could pull from junk yard that would be the right size.

yep, the SYE is the way to go. Sometimes a stock front DC / CV shaft from a newer XJ will work. but i recommend not skimping on a shaft, your local driveline shop should be able to fab you a new one or modify one that you bring in for not too much money.

 

[hunna]

if i sye it would i still need tc drop.

 

[Island XJ]

if i sye it would i still need tc drop.

pretty unlikely. I would still try the tc drop until then, assuming your shaft is not too short to need immediate attention. After you do the sye, you can return your tcase to stock. I should point out though that it is not uncommon to also have vibes from your front shaft. having the drop tc can help them too.

 

[hunna]

a tc drop is just spacer on the trannys cross member right, it just lowers the cross member and in turn that lowers the hole tranny and tc.