Ok going to change all tensioners and timing chains, and thermostat housing later this week on 1997 XK8. I feel all sorted out on these based on reading this forum, thanks a lot for being here.

I need help on antifreeze from reading here, Dexcool is maybe ok, but some say that you need to use the Jaguar coolant, has this question ever been settled?

The previous owner had the water pump replaced at the Jaguar dealer in 2007 and the car has green coolant, the car has 6000 miles since serviced and 53k miles total.

From memory reading here, the Jag coolant is yellow, and dexcool is red.

Any help is appreciated.

Charlie Pace

 

Your MY (assuming engine is original) is designed to use the traditional GREEN formula coolant DO NOT use Dexcool. Dexcool is only used in 99-mid-year and newer.

If you want a substitute use Prestone Mixes All or Zerex G-05.

 

If the pump was replaced by Jag in 2007 hopefully they would have used yellow standard coolant, not long life orange, and definately not blue/green.

The yellow can look green in the haeder tank as it is black plastic, which affects how it looks.

 

OK I'm still confused, Steve 11 says green is standard, X100 says yellow is standard and the Zerex says use Dexcool 1996 and newer G-05 for 1996 and older.

Sorry for being slow on the uptake, but I"m still confused.

thanks

charliepace

 

There was a TSB about this, and VIN up to 010343 had blue/green coolant. From that point it was Jaguar D542 (yellow) coolant until VIN 042636. For some service recalls it could have been that the early cars where flushed and got the yellow.
From VIN 042636 the orange (dexcool) was used.

iirc Jaguar recommends to refresh your coolant every 5 years, so maybe it is a good time now to do this, but then you would need to re-use a similar coolant as you have now. I have no idea what sort of coolant the yellow was, but trust that the comments from steve11 are correct.

Or even better (but much more work), do a chemical flush (as described in TSB 412-07), and switch to the later orange XLC (eXtended Life Coolant), which I think is the Havoline one (or a dexcool type).

 

Ok my vin# is 07604, so that explains the green coolant from the Jag dealer and helps my confusion a lot. So I can stay with the green or chemical flush and change to Dexcool, and Zerex G506 is not a good option option.

What do the experts recommend? Stay green or flush and change to Dexcool?

I plan on keeping this car 10 plus years driving it approx 3000 miles a year.

Thanks

charliepace

 

personaly I would flush and go orange, as the current XLC coolants are now even allowed 10 years.

 

These are the correct coolants for specific models by VIN

Early 1997 models were fitted with blue green coolant up to VIN 001245
From VIN 001246 to 042634 yellow DOW S542 coolant was fitted (change every 2 years)
From 042635 WSS M97B44-D long life coolant was fitted

 

Blue green coolant was only used to VIN 001245 so your car came factory fitted with Jaguar DOW D542 YELLOW
http://forums.roadfly.com/forums/jag...8648181-1.html

 

"How can a one-car funeral get so screwed up?" - Steve11

 

Really. Until I got this car I was blissfully ignorant that there was anything to worry about. You had your old green stuff, and several flavors of new, long-life stuff. Nobody seemed to get into trouble.

How about this question: is there any data to suggest that any of the long-life coolants would be harmful in any MY of our cars (assuming we do a flush and start from scratch)?

 

Yes there is - Do a google search on GM Dexcool and Lawsuits, get a nice hot cup of tea/coffee/hot chocolate, your choice, and get ready to read alot of online legal briefs, I have.

OAT (Dexcool being one commercial brand) is a volatile formula, but works fine with compatible materials. It will attack certain non-compatible materials (like gaskets, seals and sealants), with a tendancy to "gell" them, dislodging them and then float through the cooling system until they find a convenient place to plug. That could be a radiator, heater core or myriad valves, and engine passageways. It also does not dissolve into other coolant formulas. I would not put OAT (Dexcool) in any engine not specifically called for by the engine design group, such as a pre-1999 Jaguar as engineering hasn't necessarily specced all of the cooling components to be compatible with an OAT formula. THAT is why there is a cut-off date; otherwise, Jaguar would have issued a TSB retrofitting all Jaguar MYs with OAT

I can't guarantee a failure if one completely drained, flushed and refilled a pre-1999 Jag with OAT, but why on earth would one want to experiment in this way. Just use a formula that was specced out for your engine and MY....and enjoy another cup of coffee instead of an expensive coolant repair....or, go ahead and do it, pay me to do the repair, and enjoy the coffee anyway! I like repairs.

 

Zerex is wrong and has always been wrong. Using aftermarket charts to search for compatible components and replacement parts is not a very reliable source. These "charts" are full of mistakes, especially if manufacturers update information. The updated info is never translated to aftermarket charts.

A very good example of this is spark plugs. I can't tell you how often I find the wrong plug, or wrong temperature plug in a customer's car because that customer used an aftermarket chart to select them....I like getting paid for the repair though, when the car runs like crap after the DIY.

 

I tried to absorb all of this a few years back and my head exploded. But this much I remember as being interesting (to me, anyway).

"Dexcool" is a performance specification, not a formula. So one brand of Dexcool might be different than another. The Jaguar-branded coolant for my '01 met this Dexcool spec'. At the same time Jaguar was specifying this coolant, Ford was specifying G05 for their variant of the same engine.

When I got the car there was some sort of precipitate floating around in the coolant, and there were the stories around (which you mentioned) about Dexcool trouble. So ... I decided to switch to G05.

I gave up trying to understand everything required to be SURE this was an OK thing to do, but that was four years ago and so far so good.

FWIW.

 

For Steve11 ...

Forgot two things:

OK, now we understand why the MY cutoff for the OAT products. Thanks for that.

You think I'm OK running the G05, or would you change it?

TIA,

 

Totally confused;;;;;;;

Is there a coolant (by brand name) that will be o.k. to use in all of the xk8's???????

 

To Dennis:

G-05 is an HOAT formula developed to be a long-life coolant chemically compatible with and replaces the traditional green. It is NOT chemically compatible with OAT. Nothing is, to my knowledge. G-05 is yellow and where all the comments in this string are coming from saying to use yellow. It can be mixed with green safely and can be added to supplement coolant loss or to replace (e.g.: Avos' comment about a TSB) green. If you have a 99 mid-year (by VIN) or later, Jaguar DESIGNED the coolant system to be compatible with an OAT derivative. Either the Jaguar brand OAT or commercial, the most popular brand of which is Prestone Dexcool. I personally would use nothing in a post 99 but Dexcool, or the factory coolant if you want to pay lots of money for OAT.

To Iron Jaw:

I tried to make it simple in post #2, but it's become so convoluted that I added post #10. No - there is not one single product to use through the entire XK8 production range...unless you want to just throw caution to the wind. So, here it is again as simple as it can be made:

If you have a MY earlier than 99 (an AJ26), use green, Zerez G-05 (yellow), or Prestone mixes all (yellow).

If you have a MY later than 99 (an AJ27) use OAT like factory, or Prestone Dexcool (Orange).

If you have a 99, then your goose is cooked (LOL), only kidding. The BEST way to tell then (if all equipment in the 99 is original) is to look at the coolant header tank. If it is transitioned, you'll see a warning message to use only coolant ORANGE IN COLOR, which is Dexcool. If it does not have the sticker, stay with the first option above.

 

Um... what was wrong with the old antifreeze? Why did someone need to invent new stuff? Does it cool better? Does it stay liquid at lower temps? What are the benefits of Dexcool and why the heck did someone have to mess with something as simple as antifreeze?

I'm just griping. I know it's all about money.

 

I don't think an AJ27 is a prerequistite for dex cool. They began with VIN #031303 whereas dex cool began at VIN#042634.

 

Agreed - I tried to use it as a rough guideline, but VIN is the correct demarcation