To avoid being too verbose, I'll just pick up a few things here.

The LS did get VVT later in life.

While Mercedes might "add some extra", in the case of the G-05, the Mercedes labeled
jugs come from the same source as the Zerex for North American dealers. Mercedes
owners are just as picky as Jaguar owners and if there was a meaningful difference,
it would likely have been picked out by them.

The advantage of the LS having CHT sensors really made me scratch my head. The LS
having more "stuff" while Jaguar made do with a temperature gauge which is a
glorified idiot light and tells you nothing until it's too late. I think the LS owners
got the better end of that deal.

Additionally, they've cracked their PCM's

Grab a LS PCM and hook the AJ27 sensors to it?

 

Plums: Most of the head problems are with the early cars .. and the early cars had issues with components that if not addressed properly could lead to overheating.

Jaguar/ Ford made a mistake in the way they shared the engine technology. I have never owned an LS or Thunderbird, I don't know he differences other then Ford originally shipped over (to the USA) some blocks and then made the version in the USA. I guess they wrongly thought that this would separate the makes .. obviously it did not work.

As I said, the factory fill was not straight G-05 in the MB's nor was the old MB OE formula ... I can't comment on the new fluid that MB has moved to.

Most Jaguars owners are in my experience not as knowledgable as MB owners -- this is a generalization ... but I find more knowledgable MB owners. Many more old MB's with original owners.

I don't like to call out people on the forum -- but you have a very arrogant way of interacting with others that are only trying to be helpful.

 

Well, as Mercedes people seem to find the Zerex G-05 satisfactory, I don't see any
reason to schlep over to a Mercedes dealer to get the special secret sauce. Ford and
Chrysler owners also seem to accept it as equivalent to their OEM specs.

More importantly, the thread was started to explore the observation that the Ford
version of the shared engine has a seemingly much smaller rate of head gasket
failures than the Jaguar version. And in particular, how they "might" be related to
coolant selection.

That does not mean that I am telling you to use any coolant in particular.


Well, you're doing it anyways and you have done so in the past.

I suspect it won't be the last time either.

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