Front suspension tech ?????

Bear with me here.94 XJ 3.5" Rancho coils(sagged to 2.75), custom 1.50 poly spacers. Rancho LCA's . I am about to install HD UCA's and install new bushings in the lowers.

Here are the questions I have:

1) should I use poly or stock bushings in the UCA's ?(I have both)

2) What are the bolt sizes for the UCA's ? I am very sure they are not coming off, I would like to replace with something other than Torx.

3) What are the torque specs for both upper and lower arms?

4) Is there a specific torque procedure?

I really appreciate ALL of the great input and info this board supplies,keep up the great work everyone! Thanks in advance !

gr8lite said:

Bear with me here.94 XJ 3.5" Rancho coils(sagged to 2.75), custom 1.50 poly spacers. Rancho LCA's . I am about to install HD UCA's and install new bushings in the lowers.

Here are the questions I have:

1) should I use poly or stock bushings in the UCA's ?(I have both)

2) What are the bolt sizes for the UCA's ? I am very sure they are not coming off, I would like to replace with something other than Torx.

3) What are the torque specs for both upper and lower arms?

4) Is there a specific torque procedure?

I really appreciate ALL of the great input and info this board supplies,keep up the great work everyone! Thanks in advance !

Click to expand...

1) stock rubber

2) don't know

3) don't know and don't care

4) yeah, tighten them all

Sorry for the post in wrong topic. Hey Goatboy thanks for all the help!

gr8lite said:

Bear with me here.94 XJ 3.5" Rancho coils(sagged to 2.75), custom 1.50 poly spacers. Rancho LCA's . I am about to install HD UCA's and install new bushings in the lowers.

Here are the questions I have:

1) should I use poly or stock bushings in the UCA's ?(I have both)

2) What are the bolt sizes for the UCA's ? I am very sure they are not coming off, I would like to replace with something other than Torx.

3) What are the torque specs for both upper and lower arms?

4) Is there a specific torque procedure?

I really appreciate ALL of the great input and info this board supplies,keep up the great work everyone! Thanks in advance !

Click to expand...

1. Don't know.

2. If memory serves me correctly they're regular bolts and nuts. If nobody posts I'll climb under the Jeep later and take a look, but it's not where I can get to it at the moment.

3. & 4. My 1994 factory service manual gives the following words of wisdom.

Upper Control Arm
1) Position the upper suspension arm at the axle and frame rail.
2) Install the bolts and finger tight the nuts.
3) Remove the supports and lower the vehicle.
4) Tighten the nut at the axle to 55 ft./pds.
5) Tighten the nut at the frame brackets to 66 ft./pds.

Lower Control Arm
1) Position the lower suspension arm at the axle bracket and rear bracket.
2) Install the bolts and finger tighten the nuts.
3) Remove the support and lower the vehicle.
4) Tighten the front and rear nuts to 85 ft./pds.

I've never personally done this, but I had the factory manual for a 1994, so I thought that I'd pass on what I could find. It is kinda' interesting that the manual calls for the XJ to be lowered prior to torquing the nuts.

Hope that helps,
Robert

XJWheelie said:

It is kinda' interesting that the manual calls for the XJ to be lowered prior to torquing the nuts.

Hope that helps,
Robert

Click to expand...

The reason for lowering the vehicle before tightening the control arm bolts is so all the control arm bushings are in their "Unloaded" state prior to tightening. If you were to tighten the bolts while the weight is off the axle, when the vehicle is lowered, all the bushings would be in a constant state of stress due to twisting inside the bushing, and that's not good.

Does this make sense?