Hey, guys. I have a 2004 XJ8 (base) that has a bit of a rattle in the suspension. A visual inspection of the wheel area shows that the upper control arm's ball joint is damaged, and I assume that the bushings are worn, as well. So, following the advice in the forum, I ordered the Motorcraft equivalent part (it is indeed stamped Jaguar) and took my first crack at installing it today.

After I got the wheel off, I was intending to take the sway bar link off, then use my impact wrench or hand wrench to remove the nut separating the upper control arm ball joint from the steering knuckle. From there, I was planning on removing the air strut, following the sequence I watched in an Arnott YouTube video. However, as I started to do that, I thought I would first ensure that I could reach and loosen the two top bolts securing the upper control arm to the car. These are the two that have the "keeper" that prevents rotation. I am aware of the locations from another YouTube video, and I can get a wrench on each one. So I popped open the little plastic cover and looked at the rearward one. I do have a set of ratcheting wrenches. Bottom line is that I was unable to get the rearward one loose due to 1) the somwhat short length of the wrench, 2) the awkward angle by the hinge of the hood and 3) the bolt just seems very tight.

At this point, I decided to stop and check with you guys before I took everything apart only to not be able to loosen and remove the upper control arm. How are you guys able to remove these two top bolts? It didn't seem that hard when the guy in the video did it. Is there a way to get an impact wrench in there? Do I just need a long wrench or sturdier ratchet to get more leverage? Or, do you have to take apart everything else and do these last? I don't want to open a can of worms and not be able to finish the job.

Or, perhaps I am not correct to expect to loosen the top front and rear bolts before removing the strut?

Any advice would be greatly appreciated.

 

Try spraying with Nut Buster or another product that cleans frozen nuts. Then get a breaker bar to allow getting some leverage on the nut.

 

Those flex headed ratchet wrenches are what i used, they worked great.

 

If you have a longer standard box-end wrench/ring spanner or even an open-end wrench, try using that to loosen the nuts, then use your ratcheting box-end wrench to remove the nuts.

The right side rearward nut is sometimes obstructed by a sheetmetal bracket. If you remove the single 8mm or 10mm screw, you can bend the bracket toward the engine to give you another angle of attack on the nut. For the right forward nut, you have to work around and between the ABS modulator brake lines, which is tedious, but you can work the nut from a couple of angles and will need to use the open-end of the wrench and repeatedly flip it over, using the offset angle of the head to get the wrench on the nut for each stroke. Otherwise, you have to disconnect the ABS modulator and move it slightly out of the way, which is a pain and there's always the risk of causing a leak in one of the brake lines.

When you tighten the nuts after installing the new control arms. keep checking the keepers on the bolt heads to ensure the keepers wind up in the proper locations, otherwise the keepers tend to creep up into the wrong place.

Also, before tigthening the nuts, either lower the vehicle so the weight of the vehicle is on the wheel, or use a jack to raise the suspension to it's typical static position, so that when you tighten the upper control arm nuts the arms and bushings are approximately horizontal. If you tighten the nuts with the arms hanging down, the rubber bushings will immediately be under stress when the car is lowered, leading to premature bushing failure.

Cheers,

Don

 

Wow, that's why I hired the local auto shop to perform the mechanical repairs on both the front and rear end on my 2005 Jaguar XJ8L.

 

Thanks for the feedback, guys. I will give it another try this weekend with some PB Blaster and a 1/2 drive ratchet and breaker bar. If I can break loose the top bolts, I'll proceed with the job myself. Otherwise, I'll have to pay someone else to figure it out.

Has anyone tried a 1/2" drive flexible extension with an impact wrench? Amazon has one but I am wondering if it will work with an impact wrench.

 

You may be able to get a 1/2" breaker bar with our without a flexible extenstion on the rear nuts and the left forward nut if you remove the air filter housing. The right forward nut is obstructed by the ABS modulator and pipes. But you should not need 1/2" drive tools. The torque spec for the nuts is only 47 Nm / 35 ft. lbs., so they don't take an excessive amount of force to loosen. I think you just need more leverage than you have with your ratcheting wrench. If you don't have a longer standard box-end wrench/ring spanner, try putting your ratcheting wrench on one of the nuts, then carefully tapping the end of the wrench with a dead-blow mallet to see if you can break the nut loose. Once loose, it's easy to turn them off with a ratcheting wrench, except for that right forward nut, on which you will probably need to use the open end of the wrench.

Cheers,

Don

 

long 3/8 flex head ratchet with a mid length socket on the one that sits in the brake booster area.

for the rest you can use box end ratcheting combo. front right you can move the fusebox a little to gain clearance.

 

Hi @Don B , can you please tell me the size of the nuts (in millimeters)? Thanks a lot

 

Hi GermanXJ,

They are 17mm. I use a combination of tools to access each of the four nuts: a long ratcheting box-end wrench, a standard (short) ratcheting box-end wrench, and a long 3/8" drive flex-head ratchet with 17mm socket, and a magnet to catch the nut below the ABS modulator.

Cheers,

Don