Originally Posted by luv2fly

Nautivan, I just put these, PIRELLI CINTURATO P7 AS NCS TIRES on my 09 SV8 Portfolio. I've been running the P7 All Season on everything I own and zero complaints. Sorry for the caps, cut and paste from my maintenance log.

Originally Posted by ChrisMills

Just guessing here, but leaks in the valve block (ie the valves) may be "suspected rare" but why is that? The valves are the only "moving part" FFS (aside from the compressor).

I have no idea why people preferentially change this or that shock because this or that one goes down. The air bladders don't leak with use unless damaged (I opine!). OTOH the valves, they open and re-seal every time an adjustment is needed. Valves...opening and closing holding air...would also explain why sometimes my suspension has a very slow leak and sometimes (like currently) it is perfect. The shocks didn't change, the valves re-sealed!

I also note that "everyone" who went to coil-overs, did so because they changed shocks with no result and couldn't find the problem. I don't understand why so few suspect the valve block.

/end guess/

P.S. A leak of an internal valve in the valve block, would exhaust through the compressor arrangement wouldn't it?

Originally Posted by Jacuar

It is true that valves in a manifold will fail on occasion, but airs springs are a wear item with a service life that require routine replacement. This is because the rubber hardens with age and is prone to dry rot, which leads to cracking and splitting. I believe this is why Arnott offers lifetime replacement for their air struts (with a professional service requirement, I think).

It can be very difficult to isolate a fault or leak in the system. The air lines crack, o-rings degrade, height sensors are electromechanical and have issues, compressors have several possible failure points, and so on. Sometimes people lose patience after prolonged efforts and costs in troubleshooting this problem and exchange this exceptional dynamic system for a more reliable static suspension. In fact, I have a set of coilovers for my XJ in case I eventually choose reliability over the cool factor. In the past, I have converted several of my Rovers for the sake of reliability.

The other main challenge with air suspensions occurs when temperatures drop below freezing. Rubber loses elasticity as temperature declines (ever freeze a rubber band?) and depending on how the air springs seal to the struts, this can be a real problem. On the older Land Rovers with air springs, below-freezing temps will often cause the air system to discharge all of its pressure leading to a bumpy ride to work or the store on icy or snowy mornings. As the vehicle warms during the commute, the air springs become warmer and their elasticity, and, concomitantly, ride height is restored. More generally, it's very common for a perfectly working air suspension to be problematic at lower temperatures and then return to normal operation and reliability when temperatures rise again. My suggestion is to consider converting to a static suspension if you prefer to drive your Jaguar during sub-freezing conditions. Personally, I would avoid driving mine during these conditions to minimize corrosion potential.

Finally, something to consider:
A combustion engine consists of many moving parts, but which components (excluding fluids and filters) have the shortest service intervals? The rubber ones.

Originally Posted by luv2fly

Sentinelist, a couple of weeks ago you could still get the latest 2011 Nav disk directly from Jaguar Navigation. $200. I put it on my list as not needed at the moment. Apparently someone bought the last one since then and they are no longer available. Might find one on ebay, but I'm not sure I'm going to do that. For long distance travel, that flat nav screen makes a pretty good place to stick a Nuvi. Yeah, I know.........
I always travel with a Nuvi as backup anyway.

Originally Posted by Nautivan

Thanks for the Cinturato recommendation. Not sure what I’m going to do. My brother has an extra set of wheels from an x308 Xjr (18” I think? Not sure if bolt offset is the same). Anyway tires won’t solve my mechanics recommendation not to drive the car on salty northeast winter roads though…. One thing at a time, need to resolve the leaky valve block first.

Originally Posted by Sentinelist

I just put on Continental Control Contact Sports which are all seasons. Worth checking out, but I'm biased. Continentals always go on my cars and BFGs on my trucks.

https://www.discounttire.com/buy-tir...srs%2b/p/89652

Originally Posted by Nautivan

I have Conti Extreme Contacts on my Benz roadster and I’m very pleased with them as well….

Originally Posted by Sentinelist

And then, a beautiful set of Sepangs just appeared... at a price one would expect for a beautiful set of Sepangs... I'm going to have to sleep on it. Again. And wouldn't be disappointed if someone here decides to grab them instead. Starting to wish I hadn't just put new tires on my 19s...

https://www.ebay.com/itm/33426181737...kAAOSwayxhwLX8

Originally Posted by Nautivan;[url=tel:2494543

2494543[/url]]Indeed they do look good. Might take some effort to keep them detailed?
Did you see the 2006 portfolio sell on Bringatrailer last week? …. Wow

Originally Posted by Sentinelist

It is complete. Probably.