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Those are never stocked by me. If its a stock battery tray I just grab the group 65 with the longest warranty from wally world, tight fit but works. guess you can order the 58 still online for the 2 year battery. Battery prices have gone up a bunch and quality down, don't last anywhere near as long as they used to..

200* just isn't a problem, man. Let it rock. My all aluminum C5 corvette motor didn't turn on the fans until over 220*.

I run the Optima red top but I also keep a battery minder on it as I just don't drive it enough and that is what helps shorten life a battery. I run the minder on both the Mustang and the T-Bird and have no issues.

Amazon product ASIN B005EKY1EM
Pretty sure it works as well on a standard lead/acid battery as it does on the AGM style Optimas.

Mustang5L5 said:

There are 2 at my local wal-mart as of yesterday. Figured i'd come and do some reading and see if they were as decent as folks say. Everything I see shows they are a good battery, made by Johnson controls.

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Regarding Walmart Group 65 batteries, I tested them out with my 2000 F250 Super Duty, which requires 2 batteries for cold-cranking its 7.3 PowerStroke. Previously, I had Interstate batteries, which are/were awesome batteries, and as an aside I also believe firmly in the NorthStar brand, which used to make Sears DieHard batteries. That's state-of-the-art stuff.

Anyways, when the quality interstates had risen to $280/battery back in December 2016, I went to Walmart and bought the Everstart Maxx 65N batteries, which at the time were $93/battery. I figured at 1/3 the price, I'd get my money back out of them if they lasted 2-3 years, and they came with a 3 year warranty.

Fast forward, I finally had to replace them this January, fully 6 years after originally installing them! They weren't dead or anything, but the winter cold-cranking in the truck had slowed to the point I just wanted new ones. So, I'm sold on the Wally World batteries now, until they let me down.

Now, the one in my trailer did need to be replaced because I had run it down so many times. Exchanges at Walmart are easy peasy. Just bring your receipt and the dead battery, pick up the new one, and go on your way.

Mustang5L5 said:

I don't really think I need the group 65.

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I have DieHard & Northstar 34M batteries for the rear-mount batt boxes in my racier foxes. Dimensionally it's considerably smaller, but I was flabbergasted at the weight difference. Those 34Ms... or maybe just the expensive ones I have, are SUBSTANTIALLY heavier. I haven't scaled them, but I'm not concerned that I'm wrong on the difference. You just pick 'em up and the difference is obvious. So, I guess what I'm saying is don't jump to conclusions on battery weight until you actually directly compare them, regardless of any perceived size difference.

One more point of reference, I was using the Die Hard Battery in Black Jack, but it was small enough to slip around in Black Jack's stock battery box. So, because they're very particular about the battery being secured at Autocross events, I went back to Wally World for another group 65 battery. They didn't have the Maxx. So, I bought their 'Plus' version. I think it came with a 1 or 2 year warranty. So far it's going fine, but it's only been a few months. Guess we'll see how big a difference you get with the Maxx version.

I got my interstate battery from costco, very satisfied.
Less then a hundo$.

@nickybThe newer interstates aren't all the same quality as the old ones, but I can't complain about that price. Very competitive.

Sams club has some decent ;prices on Duracell batteries and Rural King has some GREAT prices on the rebranded Exide they carry

Mustang5L5 said:

Ok. Back to cooling system. Small drip from the bottom radiator hose. Not sure why I’m having trouble with these t-bolt clamps. Gonna swap them out….at least the bottom ones.

I am also going to change the thermostat. I’m not likening this stock temp Motorcraft. It’s slow to open so I always get a high spike, and then the temp drops. I verified with the mechanical temp guage I’m hitting 200 degrees before dropping, but this just drives me crazy.



Temp climbs to cover the R when it initially warms up. When tstat fully opens, it drops to A. However it’s like a seesaw. Then it climbs back to R and then down to A. Very slow to respond.

I still have my old 180. I’m going to put it back in. It warmed up to A and then stopped. Was a constant 185-188 degrees on mechanical temp guage. Was fast to respond and stable.

So….time to drain coolant, swap rad clamps and tstat. Gonna rain this weekend anyway so guess I have something to do.

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I have a stock Motorcraft thermostat in my 89 and it does the same thing on the colder days. Warm days I do not notice the up and down as much.

As for batteries, I am running an Interstate from Costco in the 89 that I got last summer. I had to replace the battery in my Saleen on Monday after 5 years. Costco does not carry the group 56 so I went to the local Bi-mart and got an Exide. Not sure if Bi-mart is a chain past the Pacific Northwest or not. 3 year warranty. I want to say Costco has the better warranty but I don't remember what that is off the top of my head. Costco definitely had a better price for the battery in the 89 that anyone else did. It was like $85 after the core. Paid $124 for the Saleen battery on Monday, after the core.

Costco has three year warranty. I run the group 58 IIRC.

81.99 (todays price) at Costco for Interstate group size 58.
I’ve had mine since Dec ‘17.
Just threw a meter on it and it’s 12.4V. A hair low, but still cranks the car over with no problem after 5 1/2 years.

limp said:

Sams club has some decent ;prices on Delco batteries and Rural King has some GREAT prices on the rebranded Exide they carry

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Is that kind of language allowed here?

85GTStangGuy said:

Is that kind of language allowed here?

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I guess I CRS anymore.... I edited my response.......