Because of an insured accident, both the intermediate muffler and resonator will be replaced because pipes were kinked. To replace the intermed., I am told the diff will need to be dropped.

The diff was replaced about 15,000 miles ago with a Jag rebuild with fresh fluid is working fine four years in.

But is there anything to else that makes good sense to replace while these exhaust parts and the diff are being removed?

Thanks.

 

Hi Len,

Sorry to hear about the accident and damage. There are lots of things worth checking while the independent rear suspension/differential is dropped:

Check the condition of your rear subframe bushings, the large ones that mount the front corners of the subframe to the body (part 13 in the diagram at the link below):

Frame Carrier-Rear - Parts For XJ Series from (V)812317 to (V)F59525 (X308) | Jaguar Classic Parts UK


Also check the condition of the flexible driveshaft/propshaft coupling (part 2 in the diagram at the link below). The part is sometimes called a "Jurid," "Flex Disc," or "Giubo," sometimes misspelled "Guibo" (a combination of inventor Giunti Boschi's first and last names):

Propshaft Assembly - Parts For XJ Series from (V)812317 to (V)F59525 (X308) | Jaguar Classic Parts UK


The diff output shaft bearings should be okay after just 4 years, but it would be worth checking them for oil leaks. The diff output shafts are part of the rear suspension on our Jags so they are under more stress than in many other cars. If an oil seal is leaking on one of the output shafts, you may as well replace the bearing too since you have to remove it to replace the seal (and a leaking seal is often a sign of a worn bearing).

It wouldn't hurt to check the condition of the bushings in the differential mounting pendulum, wishbone tie and strut (parts 14, 18 & 19 in this diagram). These are generally robust, but some owners have discovered that one bushing has failed while all the others seem to be fine:

Wishbone Assembly - Parts For XJ Series from (V)812317 to (V)F59525 (X308) | Jaguar Classic Parts UK


The rear shock bushings tend to deteriorate within several years (parts 5, 12, 13 & 14 in the diagram below):

Damper and Spring Fittings-Rear - Parts For XJ Series from (V)812317 to (V)F59525 (X308) | Jaguar Classic Parts UK


This will be a good time to check the rear wheel bearings.

I'm not sure how the fuel pipes attach to the bottom of the fuel tank in an X308, but if there are O-rings on those fittings now would be a great time to replace them. If the fittings are of the "quick connect" type, there may be no replaceable O-rings.


Cheers,

Don

 

Don B,

Thank you for this thorough reply. All good suggestions. I had the car up on a rack today and while the bushings look pretty good, I just may make some changes anyway.

Thanks again.

 

Also check the breather on the diff while it's down