After 15 years need to replace my battery. Any suggestions and what is the criteria?

 

If you drive the car most days, you can generally get away with a cheaper acid/lead conventional battery, one with a lower warranty. As you drive every day, it gets charged all the time and tend to last nicely for the price. You will have to periodically (once a year?) check the acid level and add distilled water to make sure the lead parts are submerged.

For the better approach though, get an AGM battery instead. They are maintenance-free and tend to be of higher quality, last longer, and cost more. I have been happy with my Bosch battery.

In the end, batteries are wear items, pay-me-now or pay-me-later type of items. The more the battery is stored in moderate temperatures in the winter and on a tender when not driven, the longer they will last. You seem to already be a champion at that with 15 years on your old one.

The technical numbers are H8/49.

PS: Be sure to re-connect the vent kit

 

I like the Bosch AGM battery I installed in July 2018. Strong, maintenance-free, and purchased on sale with a coupon from Pep Boys....

 

I just put another one of these in my 2004 XK8 a few months ago. Its the second one. First one lasted 7 years and seemed fine with zero issues. I just replaced as a preventative measure when I was updating other stuff in the trunk area

Ordering it online you can get 20% discount so ended up about $160
https://shop.advanceautoparts.com/p/...agm/10210828-P

 

After 15 years? I'd get one of those again.

 

Yes, the current battery was an original fitted at manufacture by Jaguar. Yet to get it out and see what is stamped on it! Thanks for all your comments so far.

 

You're the only person I've ever heard of who beat my 14 year original battery. Congratulations! I replaced mine with a Bosch about 5 years ago and I haven't had a problem with it. I don't drive the car much so I occasionally find the battery dead. I charge it and I'm back in business.

 

First First Interstate was strong for 8 years. It needed charging in the spring and I just decided to replace it before it gave me trouble. Now in second year on second First Interstate.

 

The NAPA AGM LeGend Premium Series is another good choice.

https://www.napaonline.com/en/p/NBP9...dInput=battery

 

Decided to purchase a Yuasa Silver High Performance battery 100Ah (HSB019). Got a good deal off e-bay. Should be delivered today. However................I have since seen communications regarding something to do with the battery needing a breathing tube. I must admit, although I have not taken out my existing 'Jaguar' battery, I haven't notice a breathing tube. What's this all about? Why does a battery need a breathing tube????

 

Not a breathing tube, but a vent. Trunk-mounted batteries can wind up outgassing dangerous vapors into the cabin, therefore they need to be vented to the outside....

 

Most AGM batteries don’t vent under normal circumstances.

However, they will “vent” if there is an overcharging condition.


Z

 

Fitted new battery with 'vent' pipe. Checked 'old' battery and it was showing 12.6v, but I had had it on charge for a couple of days!!! Maybe I didn't need the new battery after all?????

 

First thing I did after I bought my '03 XK8 'vert in 2011 is change the batt. Got a lead-acid Duralast Gold from Autozone and it has been in there for 9.5 years. Must have gotten a good one ... still cranks strong, no weird electrical stuff going on. Just for grins had it checked and was declared quite healthy. It was $145.99 plus tax back then... looks like AZ charges $159 for the Gold and $199 for the Platinum today. Of course, the warranty long expired.

 

Out of interest, there is a 'gold' coloured bolt adjacent to the battery which on the face of it doesn't appear to do anything. Does anyone know what it is for?

 

I've a different model (with a different bolt that goes much further in) - used for the clamp to hold the battery in place should the car turn over.

 

Yep, that bolt holds down the clamp you are missing....

 

I also have that gold coloured bolt + my clamp is fitted and bolted through the hole to the left of the gold bolt.
I have always thought it is just there to stop you from placing the battery any further to the rear of the car, protecting the wiring and black plastic box shown in your picture. It also stops you from covering the hole that the clamp bolt fits into.

 

Here's a photo showing how the strap should be installed. The vent tube is installed on the far side of the battery and extends through a grommet in the floor.

 

Can't see from your photo, but the week and year of manufacture of the original Jaguar battery is stamped into the top of the -ve negative battery terminal.