Hello XJ40ers,

I fell into a problem where I ordered the front lower A-arm poly bushings from Powerflex, for my X305. They claimed their set of these would fit 1988 XJ40 straight through to 2003 X308. While installing I was shocked to find that the bushing was too small, by at least 5mm in diameter. Today I discovered that my early build X305 uses the older XJ40 style front lower control arm and bushing. At vin 722477 (X300, only 2000 cars in), the front lower control arm and bushing was updated. So I now have a new bushing installed that is too small for my car's older, larger diameter bushing hole!

Old lower front A-arm bushing: CBC2291. New bushing after vin 722477 (X300): MMD1361AA. Apparently NOT interchangeable. Inner sleeve diameter and length are still correct on the Powerflex, so luckily I could use it to "improve" on the old disintegrated bushing. And it has improved the steering and handling. Powerflex kit PFF27-401.

I've done more research today and have confirmed the difference. In the meantime, hold off ordering any front lower A-arm bushings from Powerflex. Apparently they are too small in diameter for older cars, to include all XJ40. I will keep you updated on any developments.

 

That is a very confounding problem. If you knew a machinist, maybe they could make you a bushing to fill the gap?
In the meantime, did you make Powerflex aware of the discrepancy?
Thanks for letting us know.

 

I sent them an email this evening Jerry. I don't know what they can do about this, but maybe I can get a refund. I don't think I will be able to get a correct fitting Powerflex. Which is unfortunate because they are tough, and are made in 2 pieces and so are very easy to install compared to pressing the original style into the arm.

Hopefully they will concur that the fit is not correct for older cars and can at least remove those from the market on this particular bushing.

I did not measure the diameter of the A-arm hole, and I should have. The Powerflex is not made with an outer sleeve, so I re-used the outer sleeve from my original that I had cut out of the A-arm before I noticed the size difference! It helps to take up some of the slack.

I needed the car last weekend for a road trip, and this bushing was all that I had to install last week, so in it went. It actually worked quite well and the car tracked straight and steered better with the new bushing and quick DIY alignment check and adjustment after the install. The spring pushes strongly downward and outward on the bushing so it is really not loose per se. Had a very nice drive to the eastern Arizona mountains for an event.

 

probably just a garbage bushing which is synonymous with powerflex. or they expected you to just walk the rubber out with a drill and install it with the old shell

SNG doesn't even bother to list the later part number and Berkshire says MMD supersedes CBC, so it's almost guaranteed to be interchangeable. they also have a polybush brand offering.

 

So the sloppy fit of the URO brand replacements is not unique by the sound of it? Someone got the specs wrong maybe?

Larry

 

Good news for the XJ40 crowd, Powerflex has confirmed the set of bushings they sent me will fit the XJ40 and X300 up to vin 722476. EXCEPT MINE. My car has newer updated A-arms, both sides, which use a larger bushing. The A-arms were also supposedly updated at 722476. But my car was built 2000 cars BEFORE the changeover point! How did that happen?

The "discrepancy" is verified by Jaguar classic parts. The parts data versus the real world build do not match up, which is not so uncommon. But it doesn't affect you XJ40ers, you can order up and they will fit. Probably better than the other aftermarkets and they will be much more durable.

My man at Powerflex was very responsive and helpful. He contacted the UK designers to verify the dimensions, and then I found the anomalous A-arms residing on my car. They have already updated their site to remove the mistaken fitment for later X300 and X308s. Now to see if they can get me the actual right size bushing for the X300.....

 

Just throwing it out there- Is there any chance that your front suspension has been changed?

 

I suppose its possible, in the early days before 2010! Although I don't know why. Both sides have the newer control arms. There is no record of any prior accident or damage. Replacement of both sides seems unlikely.

I am still not convinced the bushing sizes changed, although Powerflex assures me their bushing is correct for the older vehicles that use the older control arms. Anyway I'm getting half a refund. Unfortunately they don't know of any bushing they sell that will supposedly fit the later models. But my investigation isn't over yet....

So why the changes, Jaguar? They can't change the specs of the control arm without affecting all the other attached parts. The bushing bore size may have been increased, which explains the bushing update at the same time. If the dimensions of the bushings are actually the same, they might have upgraded the rubber material they used in them. But in that case why would that require an update of the control arms?

Here's a general question: When Jaguar changed suppliers (manufacturers) of parts, would they normally change the part numbers too, even if the specs were the same? Does the prefix of the part # identify a particular manufacturer?

 

Hi Richard,

More than a few times over the years I have encountered instances where the VIN noted for a part change in the Jaguar parts catalog is inaccurate, and that the part change actually occurred earlier or later, at least for the particular Jaguar I was working on. The parts guys at our local Jaguar dealership have told me this is very common in the Jaguar documentation.

Regarding the part numbers, I do believe that changes in the four-digit number or the two-letter suffix may indicate a different production run or different supplier. But if you review the supersession trees in the parts catalog you'll see examples when an older number like a C2C**** supersedes to a newer format like MNA****AA. Often, those kinds of part number supersessions seem to correspond with carrying over similar parts from the XJ40 to the X300 and X308. You'll also see many XJ40 part numbers that begin with JLM, and that is a numbering system that dates back to the Series III XJ6 and XJS.

Cheers,

Don

 

So I ordered one bushing of each part number, and they are indeed the same diameter. The only difference is the metal inner sleeve is 2mm longer on the newer part #. All other dimensions were the same. This basically means that either bushing should fit all XJ40 and X300. Powerflex hasn't figured out that their 38.5mm bushing with no outer sleeve is not equal to the 45mm original size. Someone goofed. But they insist theirs is correct for the XJ40.

I relied on their data twice, and have proven it wrong twice! Sorry for the mis-information above in deciding that the bushing sizes were different.

Here is the link to the X300 thread for easy reference: Powerflex bushings don't fit?

Thanks for that information, Don. I was going to ask you that question directly. I guess I didn't have to!