2004 Battery "upgrade" to AGM

[Rawah652]

Has anyone been running an AGM battery in their retro bird? Any issues?

Backstory to the question- I forgot to connect my battery tender when I left the car in winter storage, so my battery is now basically a brick and needs replacing. Unfortunately, none of the options that I can order at local parts stores to replace it have the vent system necessary for safety in the trunk location. i.e.- there is no where to connect the vent hose to the battery. This is less than ideal.

AGM is a great replacement option, as it has none of the venting issues that the original batteries have, can be ride in this location safely, plus a few other great features- though it will absolutely require me to not forget to hook up the battery tender 🙄. Obviously mounting needs to match up, which it appears to. The AGM battery I'm looking at meets all the specs of the OEM battery, is there anything else with the car's electrical system that I'm missing that I should consider?

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[tommyc]

Not sure about the AGM batteries. Never used one myself. But I'm surprised you can't find a vented battery. It's group 66. A lot of parts stores (and even Ford) will tell you a group 65 battery will work. It's essentially the same size as a 66--sans vent connection.

A quick search shows AutoZone has a Duralast in 66, and Advance has a DieHard. Interstate has one called MT-66, but I had to go directly to their website search tool. Price may be about the same as the AGM you want to try.

Hope this helps. Good luck!

 

[Rawah652]

There were a couple in the database lookup at OReilys, but they had all been discontinued and couldn't be ordered. The rest available were non-vented (or at least, had no connection for a vent hose.

 

[Duncan]

Last year I had to replace our 10 year old battery. The local Ford dealer was able to order the correct vented battery. Part # was BXT-65-750 and cost was $187.20. Had to wait 2 days for arrival, but it was cheaper than any of the parts stores.

 

[T-BirdTom]

I used Optima batteries (AGM) in my race cars as they were far less prone to failure due to vibration. I've continued that practice in my street rod and am on my 2nd one since 2009 (replaced last year). So, from a durability point of view, they're nice. Finding a size (and terminal location) that matches might be an issue as they don't have a lot of variety.

Optima had an exclusive for a long time, but it now appears there are several producers of these battery designs. (look like a 6 pack of beer). I'll be interested in what you find. My T-Bird battery is relatively new, so it will be a while before it's again replaced.

Thanks for bringing this up.

Best wishes,
Tom

 

[SteveG]

About 2 years ago I elected to replace the dead battery in my 2005 with an off the shelf AGM. I drive the Bird very little, and keep it on a battery tender. No issues, but realize that the recharging profile of the car does not match what is ideal for an AGM, so it may result in a shortened battery life. Since I drive very little, the battery is mostly receiving the battery tender profile, which IS optimized for AGM.

 

[James Shoaf]

I purchased a Duracell Ultra Platinum AGM 750CCA BCI Group 65 SL165AGM .. from Batteries + .. $220.07
Working great no vent needed .. keep it on a trickle charger .. ...