The right front [EDIT: lower] A-arm bushing was shot. I was compensating by running a large amount of toe-in on the right side, but this needed to be fixed soon.

Am I the first one ever to buy the Powerflex lower front A-arm bushings? Because they DON"T FIT. Not even close. The bushing is at least 5mm in diameter too small for the arm. Luckily the other dimensions were correct, such as inner sleeve diameter and length.

That allowed me to use the bushing as it was, since I could not have the car out of commission for long. I actually re-used the original outer sleeve that I had hacksawed out of the A-arm in two places (which worked well) in order to take up some of the slack around the new Powerflex bushing.

The result is satisfactory, if not correct. The car tracks, steers and handles better with the one replaced bushing. But I am not happy that I will have to do this job again, IF I can get the correct bushing. I used the 6-threaded-rod (M8 size) method for spring drop and it was nightmarish tedious.

The box and bushings are marked with the "correct" Powerflex part number (PFF27-401). Is there supposed to be an outer sleeve? I haven't contacted them yet but wanted to find out if anyone else had seen this or it was just a very unlucky fluke.

This same bushing is used in the XJ40, X300 and X308 so I can't imagine they have been selling flawed bushings all this time [EDIT: incorrect, as there was a change at VIN 722477]. I double checked my order and the Jag part numbers and all was correct and matched up according to the Powerflex site. Until the new bushing almost fell through the A-arm hole!

 

What's the part number we're talking about? If you're talking about the upper control arm bushings, CAC9295, you can just release the upper ball joint by removing the two bolts that hold it in place. I don't know why you would have needed to mess with the spring.

 

It is the lower front right bushing that was shot. Jag part #CBC2291 / MMD1361AA. The part number was updated at vin 722477, my car being made prior to the update at 720xxx......

Now I have discovered that the lower front control arm was also updated at vin 722477. That could be the point from which a smaller bushing was used! However, the Powerflex site shows the Jag bushing part numbers as interchangeable (the same size) from 1986 XJ40 all the way through X308 (showing both Jag part numbers). That is what I relied on.

Reliable reference source Jagbits acknowledges that the older lower bushing CBC2291 fits only up to 722476 and the updated MMD1361AA fits only from 722477 forward. I think I just solved my own mystery. Next time I will do more research first.

So I could be the first guy to order the Powerflex for a very early X300 (or XJ40) and now it is my duty to inform them of the discrepancy. A very unlucky fluke: I didn't notice a discrepancy, nor did they.

 

My contact at Powerflex has been very helpful and responsive. We have exchanged a lot of information thus far. The UK designers were consulted.

Turns out the set of lower front A-arm bushings I ordered are in fact correct for the XJ40 and X300 up to vin 722476. The problem is that my early car (720470) has the LATER style lower A-arms (also updated at 722476). The later versions use a larger bushing. Both left and right sides have the newer A-arms on my car. I don't have any knowledge of the arms ever being replaced due to damage but that seems unlikely.

The lower front bushings they sell for the XJ40/X300 DO NOT fit after vin 722476. This same set is not correct for the X308 either. Powerflex has already updated their site as they re-evaluate the different A-arms and bushing sizes. They already sell a different kit for the X308.

All of this information would not have helped me, since I had no idea my car has the later control arms with the bigger bushings. I don't know yet if Powerflex can come up with bushings that fit later (most) X300s, and mine. We will find out shortly. There is some discrepancy in the service data versus the real world builds. Not the first time. So be sure to check your lower A-arm part # before you order their X300 bushings. At this point the Powerflex will only fit lower front A-arm part # CCC5576 (right side #). The number is cast into the front of the arm, easy to see. If you have an early vin car, go take a look and report back!

MMD1346AA and CCC5498 are the newer, larger diameter A-arms (right side). Same (larger) bushing used in both. Left side part numbers are 1 digit higher. At least the car is driving better, even with the smaller bushing. It is much better than what came out of it.

Link to the Jaguar Classic site parts bible: Jaguar Classic X300 front suspension

 

Hi Richard

This may not help and indeed may just add to confusion.

I fitted a kit from Polybush ( https://www.polybush.co.uk/ ) many years ago when I rebuilt my car. At the time they did not list a kit for X300, but I was pretty confident the XJ40 was identical so I ordered their XJ40 kit (Kit 56 on their site). The bushes fitted perfectly.






But here's the thing. My car is VIN 724918 and it has the later arms as per your description above (CCC5499 on left).







If you look at the Polybush web site today, the kit for the XJ40 and the kit for the X300 contain the same parts for the lower wishbone bushes.

 

Thank you Brendan, we will see if I've been blowing smoke. Or smoking blow. I see what you mean with the Polybush site. They make no distinction between XJ40 and X300, not even mentioning the superceded part number for the bushing at 722476. CBC2291 ---> MMD1361AA.

The Uro bushing can be found by the two distinct part numbers, but don't cross reference as the same Uro part. Although they are both usually described as fitting all cars XJ40 through X300, which implies that they are the same part and size!

RockAuto says the CBC part number bushing (Uro) fits up to 722476 but makes no reference to newer cars (for the XJ12). EDIT: RockAuto shows both part numbers for the 1995 4.0 cars, with the changeover point. They are Uro and each has its own Uro part number!

They all could be the same size. An implied size difference due to an update could be a myth. But we are here to get answers. It could be that Powerflex had it wrong all this time, and that would surprise me too.

 

Yesterday I received these two new Uro Parts OEM-style lower front A-arm bushings, one older part # (left) and one newer part # (right). The only difference I found was that the front projection of the metal inner sleeve is 2mm further out on the updated, newer part #. The inner sleeve is 2mm longer overall. The end of this sleeve is in contact with the front fulcrum tie bar and the tie acts as a washer for the fulcrum nut. So this is possibly the only reason for the part update at vin 722477.

All other dimensions were the same between the two Uro bushings. The diameter is the same, just shy of 45mm.

The Powerflex bushing is only 38.5mm in diameter. So no matter what I've been told, their bushing is too small in diameter for any application to XJ40 or X300. The inner sleeve was of the older part's length, 2mm shorter than the updated part #. The other dimensions were correct for the car.

When I did this job I inserted my old cut outer shell from the old bushing back into the A-arm in order to take up some of the space with the Powerflex undersized bushing. I had no other option to get the car back together at that point. There was still 2-3 mm of play. A hack I'm not proud of. The new Powerflex bushings do not come with an outer shell.

The new Uro bushings seem to be durable. The rubber material seems about as hard as the Powerflex poly material. I'll probably fit one on the lower left side to see how it goes, then eventually replace the right poly one again.

My apologies for the mis-information in post #4. More evidence has been uncovered. The OEM-style bushing diameters old vs. new are the same. The change in part simply gives more clearance for rotation of the A-arm and bushing at the front tie bar.

I think I'm done now!