94 4.0 XJS Facelift alignment

Very interesting. Thanks.

Oh, on the rear suspensions, one big difference of course is the inboard vs. outboard rear brakes. But I assume you’re saying the rest of the two systems are alike?

Working on the Rear Cage another milestone has been reached. I got the cage and the diff all cleaned up, dismantled the control arms, and cleaned them up. During dissemble it became that everything was worn and I happy that I decided to go all out and renew everything. Below is a photo of just one set of bushings and bearings, the bushings clearly show wear marks from the roller bearings, but all were worn, but not only that they all had various amounts of play. In my view the rear end takes a lot more abuse than the front, but gets the least amount of attention. Its also obvious why that is, the rear is more complicated and much harder to work on.

Instead of using the three ring circus of spacers and seals I decided to up the ante and never worry about the fulcrum shaft bushings again, so I went with brass.

Not only did the brass render a much tighter fit but it also eliminated the endless fiddling with the OEM rings and seals

Now that, that’s done its time to move on to the hubs.

Your old bearings actually looked pretty good. On every car (and these are all Northeastern cars) that I worked on, the bearings were solid with rust. The center was often worn oval. On sweeping curves on the road, the fulcrum would move from one side of the oval to the other and the cars would have the most insane twitch! The bronze bushing you installed are borderline CHEAPER than the OEM bearings too. They are the only way to go.

They certainly weren’t cheaper than the OEM bearings. They were however, much tighter fitting than the needle bearings, so I do expect so feel a difference (time will tell, I guess.)

The cars got a little over 50k on the clock and it lived and never traveled outside of Northern California until I bought it, so inclement weather is not something that it saw (zero rust).

I see you removed that rascal check plug on the differential cover. Just want to verify that it can be removed using just the bare end of a 1/2" socket drive. ? :confused: I was in WM the other day and saw a 3-piece drive extension set (the black metal type, no less :+1: ) and thought of the task. If you snap all 3 pieces together it will extend a total of 18", IIRC. That should plenty to reach the check plug from underneath, or even via a 2" hole drilled in the boot bulkhead like (VK? Gregmatic?) created … :joy:

Good work A.J !
Never the less, I see no shims between the fulcrum shaft carriers and the diff…

Are there any seals on that brass assembly?

There are no shims to deal with and that was of the reasons that made using this setup so attractive. The brass bushings and the thrust washers are both machined to take up the space of the two rings & seal. The two original outer thrust washers are the only pieces of the OEM setup that are retained.

There aren’t any seals on the assembly, so there’s nothing to wear out. The only downside that I see and I don’t know how practical or detrimental it is, the recommended grease interval is 4,800 km / 3,000 miles. What are you supposed to do when you are lapping up the and putting on 7,000 - 10,000 miles in a clip? I dunno

I’m sorry, but I just don’t know what this check plug is that you are referring to?

The ROM say that the torque values for the outer fulcrum shaft nuts should be torqued from 131-145nm.

The question is when should these be torqued? I could torque then now with the cage upside down, I could torque them after I flip the cage over to it’s natural position where there is more weight pushing down, or lastly, do they need to be torqued after the cage is installed with the full weight of the car? I Dunno

There’s no rubber involved, so it shouldn’t matter. You usually torque rubber bushing when the car is on the ground so they don’t rest in a twisted position when the car is static.

Btw I know nothing so consider ignoring that :slight_smile:

1 Like

I agree with John6, it’s immaterial when you torque those nuts up with the setup you have, even with the original bearings it’s would be the same situation as John6 states there’s no rubber bushes to twist.

The (hard to access) plug - female square socket - to check the level of the lube in the rear differential. :angry:

I absolutely did not ignore that. Didn’t have enough words to satisfy the minimum requirement so I issued a :heart: instead :blush:

Yes, the point was well taken.
Thanks guys

Yes, I did use a ½” square to remove the diffs fill plug.

Nothing to do with the bushings setup, I was talking about the shims between the shaft carriers and the differential case, so the shaft aligns with the holes on the cage.

The photo is zoomed in to much for me get proper perspective, but nevertheless there are no shims, and I positively did not remove any shims. Are we talking about the same model years? Whatever can be seen in my photos is exactly as it was found, except for the new bushings and of course the half shafts aren’t mounted.

It’s the fulcrum shaft carrier (the wishbone is missing),the part on the bottom is the diff and the part behind is the cage.
The point of this exercise is to align the shaft carriers to the holes on the cage so the shaft can go in easily and not bend.
The fact that it had no shims says nothing, they could have fallen out, or not put in by someone else that worked in the car. I had a couple missing in my car and had to use a big fat hammer to take the shafts out.
If inserting the shafts after you tightened the carriers at the diff required minimum force, i.e. by hand, then you are ok.

BTW it’s also a possible way to correct rear toe issues.

Trying to renew the rear cage has been long time coming. I’ve found that a lot of parts mixups are due to the propensity of parts suppliers to default to pre-facelift options which has resulted in big time delays. It also took quite a bit of time to decipher through the differences between the various part numbers of the rear subframe mounts. The mounts for the coupe, and the convertible are exactly in every way except for the durometer of the rubber, with the convertible being the softer of the two.

After taking into account my choice to use big & small Poly bushes on the radius arms

it seemed to make sense that all of the rubber associated with the rear cage operates within a system, so I opted for rear Poly subframe mounts as well.

I will also be adding an anti roll bar to the rear, but still undecided about using Poly on the end links.

It didn’t make much sense to bypass dismounting the rear brake hard lines and cleaning them up. I’m glad that I did because I was able to find and clean rust out of the fittings.

Its finally time to mount the cage

1 Like