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Why does manual(s) state shock must be compressed for removal?

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Old 04-13-2006 | 08:20 AM
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Default Why does manual(s) state shock must be compressed for removal?

I've done a search and though close I could not find why the Bently and Haynes state that the car must rest on it's tires/shock compressed. I agree with the other replies in that I had to raise the car to access the lower bolts. (What a bear to get off!)

I did try to simulate the car resting on its tire by placing a floor jack under the trailing arms and raising the jack until firm contact. I then lift the car up with the regular side jack, removed the tire and lowered the car back onto the floor jack.

What are the manuals getting at? Was this for self-leveling suspension? Why make it harder to remove the lower bolt with the added force of the shock?

FYI I am replacing Bistein with the same. The rear is done. I just looking for input. I am sure it will be blindingly obvious once pointed out to me.

Also how did anyone torque the right rear top nut? Even with the air box cover gone I didn't have enough swing clearance.

Reg
Old 04-13-2006 | 11:05 AM
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No ideas here... I've always done it with the trailing arms hanging...
Old 04-13-2006 | 07:00 PM
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I also did mine with them hanging. With regard to your second question. It is tough to get back there, but I just got it as tight as I could and then rechecked it a couple times later to make sure it didn't loosen. It hasn't yet and that was three years ago.
Old 04-13-2006 | 08:45 PM
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Reg: The easiest way to remove the rear shocks is to, with the rear of the car off the ground (supported by jack stands/hoist, or other means that are safe), raise the rear suspension using a floor jack under the tire (e-brake set). In the compressed position there is no lateral load on the lower bolt, hence no chance of damaging threads. Installation is the same, after the upper nut is started go under the car and compress the shock until the bolt is easy to start by hand. Before you lower the rear wheel torque the bolt - you will notice that if you torque it with the suspension hanging, there will be a slight twist (pre-load) on the lower shock bushing, which is not good. In other words, as you compress a shock that is torqued in the hanging position it will start to bind. You want those lower bushings free to work properly with the car on the ground, if they're pre-loaded they can't.
Pete
Old 04-14-2006 | 09:28 AM
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I did exactly as Pete has described it , I had to go up and down a few times to get the sweet spot so I could start the bolt by hand. The top I jsy tightend until I heard the rubber start to twist and that was good enough for me ..
Old 04-14-2006 | 09:34 PM
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Pete,

I am not sure if I did exactly as you however, each bolt was removed, reinstalled and torqued with the shock compressed. The rear suspension rested on a floor jack during each evolution. Torque was rechecked with the tire installed and on the ground.

Any advice for the front? The guys at Pelican say the front does not require the extensive disassembly described in the manual. True?

Reg
Old 04-14-2006 | 09:56 PM
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Reg

You should search for a thread on this as I have just finished it . I went from Boge to Bilsteins up front and it was sooo easy.

1.put car on jackstands.
2. put low tack painters mask around lip of fender covered by duct tape
3. unscrewed nut inside of cargo area and pushed down piston through body, took off dust cover
4. used air hammer to unscrew strut cap , or masive channel locks would work.
5. Swing out strut from under fender after compressing all the way by hand.( watch for stressing rubber brake hoses but it will work )
6. lift out insert
7. use suction to suck oil out of strut ( old boge is hydraulic )
8. Pop in insert
9. installation is revere of removal.

optional work , good time to change rubber brake lines if they are looking stressed and it makes doing the cartridge a little easier.

If doing brake lines remove caliper and do wheel bearings.
Old 04-15-2006 | 09:09 AM
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Appreciate it Iceman,

Will do coming week. No plans for brake lines but I have new turbo tie rods standing by. Brakes pads and rotors after that. Finish oil tensioner line upgrade, replace motor and transmission mounts, change transmission oil . . .

Reg
Old 04-15-2006 | 10:40 AM
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Well certainly you must support the bannana arm a bit to get the shock bolt in and out properly, but I read "Compressed" as "Fully compressed", perhaps my mistake. I use a second small jack under the arm to move it up and down so I can thread the bolt in my hand, eliminating any chance of cross-threading.
Old 04-15-2006 | 07:19 PM
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[QUOTE=theiceman

4. used air hammer to unscrew strut cap , or masive channel locks would work. [/QUOTE]

No such piece on mine. The cartridge is held in the strut housing by a pin that engages the detent on its bottom.
Reg

Last edited by afinepoint; 04-15-2006 at 07:51 PM.
Old 04-15-2006 | 09:51 PM
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Reg

Then you do not have boges in the front you have Bilsteins and can drive or drill out the pin. I think you have to be selective as only certain strut cartidges will fit. I think you have to put Bilsteins back, they come with a new role pin.

I just did the turbo tie rods, petty straight forward. the only real trick is to disconnect the outer from the arm ( don't unscrew it ) by pushing or prying it out. and when the arm drops use it as it's own wrench and unscrew it from the rack. then measure and make the new ones the same length before assembly. Since you have the belly pan off you could change the inside sway arm bushings since you are 2 bolts away..
Remember if you do the rotors the calipers have to come off and you have to take the brake line off anyway. as the hub has to be removed, may as well repack the bearings.
Transmision oil is no biggy .. only tip is make sure the filler plug comes out before you open the drain plug.. I used swepco and it worked really well for me .. but boy did the old stuff stink .. what an acrid smell...
I haven't done the motor mounts or transmision mounts .. quite frankly just never thouht of it ... hmmm.... I sense a project coming..
My tensioners are done allready so I don't get to do that project .. but I am keenly waiting for my clutch to start slipping as THAT one sounds interesting .. am i sick ???
Old 04-15-2006 | 11:42 PM
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Front shocks are done except for torquing the top nut. I can't find a C-spanner wrench locally. The tape on the fender was a good idea.

Whoever came up with the bottom pin must have also worked with Ford. My Explorer has the same pain-in-the-butt design for the brakes.

Ice, a significant contributor to shifting problems with a (915) transmission is misalignment between the engine and transmission due to aging mounts. New mounts will reset things.

I intend to use Mobil 1 in the transmission. This and the turbo tie rod installations are next. The mounts are down the road. Probably a winter project.

Reg
Old 04-16-2006 | 12:25 PM
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Reg

definitely gonna do those mounts , sounds like a good project for the winter for me too. I took the engine ones out just to look at them .. but the transmission ones looka little more involved... like I am gonna need a 14ft breaker bar and do it from my neighbours driveway .. I fancy doing a clutch this winter so maybe I will combine the 2 .
Old 04-17-2006 | 01:09 PM
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Never heard of the torque tecnique, thx.
I slimed the top and bottom shock bushings with dielectric grease(silicone) so they'd move if they had to. It will probably also helps prevent air penetration-which dries out rubber.
Old 04-17-2006 | 02:34 PM
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Reg: You stated that you want to use Mobil 1 in your trans. I certainly hope that you meant to say engine! NEVER put synthetic gear oil in a 915 transmission!

Ice: The forward trans mounts will be easy for you. With the car in the air remove the (4) 8mm bolts that hold the sway bar (2 at each end) and let the bar hang from its drop links. Put a floor jack under the trans. With slight jack pressure against the trans use your impact wrench to remove the large bolt in the center of each mount. Use the jack to lower the trans slightly until the mounts are free (you don't need to loosen the coupler). Remove the (4) 8mm nuts in the center of the mount plate, remove the plate, put it in your vise, replace the mounts and torque their bolts (you can do the mounts under the car but dirt gets in your eyes, etc., and you can't do as good a job cleaning the area). Install the plate, snug the four nuts but don't tighten them - you want to be able to move the plate using a little sideways pressure. Adjust the trans height so you can just slip the two upper washers into place and use a pin punch or similar object to move the trans plate so the big bolt holes line up. Put the two big bolts in by hand - it's easy to cause thread damage if you don't - snug them by hand and torque them to 65 lbs/ft. Torque the 4 plate nuts to 17-18 lbs/ft, put the sway bar up and you're done.
Pete


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