The information has just come about that there is a fourth generation secondary tensioner. The third generation looked pretty good to me when installed mine. Has there been a failure of the third generation. Otherwise why did Jaguar make another design change.

I would like to hear from anyone with knowledge on the subject. I plan on keeping this car for a very long time.

Thanks guys and gals

 

I don't know what is different about them as yet just that when I bought them a few weeks ago they were listed as "4th gen" and some of the other sellers were also listing them that way.



Dave

 

I just looked up some pictures of the 3rd gen tensioners and they look physically different than the "4th" gen ones I bought. Mine are less massive and the shoes look like a different design.
I wonder is this was done because of problems with the "3rd" gen units or if its just because the bean counters wanted to make them cheaper.
I can't find anything that tells why these came out over the other ones.



Dave

 

what gen is in a 03 Xk8?

 

That would be 3rd gen it seems. The 4th gen seem to have started appearing around 2011 or so. I could only find one reference about them with some more looking and it seems they came out to match the newer "Morris" type chains but allegedly are still ok for the old roller type chains.


Dave

 

The generations, in big general terms was (1) original plastic, (2) external spring assisted original plastic, (3) metal with ratchet operation. I am unaware of a 4th generation tensioner except by forum comments.

I have no way to confirm this information but a member, several years ago, posted that between the left and right tensioners there had been a total of 21 part numbers. Sounded like a knowledgeable comment at the time. It is common practice in the auto industry that you change the part number or like Jaguar is fond of doing, the last 2 alpha characters anytime you make a design change in the part.

Witness GM's recent big public/legal blow up over changing the ignition switch design and not changing the part number.