Any informed opinion out there on valve regulated lead acid batteries versus flooded cell lead acid batteries. As I understand it, the first type is the "no maintenance" battery and is somewhat shorter lived; the last type has accessible cells and should last longer.

Everyone is trying to sell me much smaller batteries than the long battery which matches my factory mounting and wiring setup. They claim its what their "computer" recommends for my car and they're all sealed with no removable cell covers.

 

I've got a duralast gold battery in my xj6 and it's the smaller size. If you look at where the battery goes without the battery installed you'll see two different mounting holes. One for the larger long battery and another for the shorter battery. The mounting hardware is different for the two sizes. For example in my xjr it has the longer battery installed and the hardware to hold it down is two long bolts and a bracket that sits on top of the battery and the bolts tighten it down. In my xj6 with the smaller battery it's got a little L shaped plate that bolts on the trunk floor and kind of pushes the battery against the trunk wall and sandwiches the battery into place.
I'm not really sure why autoparts store don't require the larger battery when from the factory they were larger, but I'm guessing it has something to do with fitting larger capacities into smaller form factors with newer batteries?

Now my mom's XJ6L has a duralast platinum battery and that is the longer battery. Platinum wasn't an option for my xj6 when I had to get a replacement.

 

Your up there and I am down here, and the markets are worlda apart.

My X300, and the 2 S Types all have what we call the N88 (DIN88 in disguise) and all batteries of any quality here are "maintenence free" design.

The X300 battery is now 6 years old and sweet as. The Black S is 7 years old and also sweet. The Silver S is 6 months old, and the old one was 6 years old.

The aftermarket catalogues are a JOKE, and harder to decipher than a Chinese Takeaway Menu. I work in that industry (Aftermarket Auto Parts), and that is the most frustrating part of the industry.

Any half decent Auto Parts operation should be able to cross reference the DIN88 to a suitable battery in your market. If not "good old Google" will help.

 

Almost sure the X300 takes the same battery size as the X308.

Group 49 or H8

It must be remote vented.

Costco does not sell that size. Walmart does.

Deka makes an excellent battery in that size in both maintenance free and AGM. The Napa private label is usually Deka.

All the major brands have a Group 49/H8 in their catalog. Interstate, Johnson, East Penn

http://www.dekabatteries.com/assets/base/0379.pdf

++

 

Thanks AlbBolivar, Grant Francis and Plums for the helpful information. I ended up getting a group 49(H8) which is a perfect fit even though the stores computer told me I needed a 48.

 

I just had this "dispute" with the guy at Sears when I purchased a battery for my '96 XJ12. The books they have, and everything in their computer (as well as all the leading battery manufacturer's websites) shows the compatible battery as being a Group 47 (H5), which is way too small, and physically too short to fit the stock mounting holes and cables.

The dealer's battery chart shows the Group 49/H8 as the correct size for my car, and the X300 XJ6 as well. Everyone else wanted to sell me an H5. I had to have the parts guy put the sale through as an 1996 XJ6 instead, and had him cart the battery out to prove to him it was the right size...

I ended up going with the Group 49 (H8) Duralast Advanced Gold AGM. The Interstate that was in the car never failed on me, but was showing signs of weakness.

Nick

 

So they weren't just picking on me! Seriously, I've read that some BMW and Mercedes owners have encountered the same thing with battery sizes. Maybe the manufacturer is trying to reduce overhead by switching us to smaller format batteries.