1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Replacing an OEM Kei car/truck/van battery

Discussion in 'Tips and Tricks' started by Gar Vance, Jan 13, 2021.

  1. Gar Vance

    Gar Vance New Member

    After scouring the internet for information on an OEM-sized battery to fit my '91 Daihatsu Atrai van, I found a great choice locally and thought I'd share as it might help someone else.

    My Japanese Unistar battery (made by GS Yuasa) died after only 11 years! I was shocked it was that old!! It appears that most kei vehicles end up using "garden tractor" batteries because OEM-sized batteries are not available in the US. These smaller batteries are readily available at Walmart and other stores for $25-$35, however the connectors need to be changed out to fit the positive and negative terminals. Also, the battery reviews are generally terrible and warranties are as little as 3 months. Bottom line: you get what you pay for.

    Long story short, I found a great "full-sized" replacement car battery that fit perfectly: a Duracell Group S46B24R battery (often used in a Toyota Prius.) It uses the same size "pencil post" terminals as the OEM battery, has fantastic reviews and a 4-year warranty. The downsize is that with discounts and my old battery core, the cost was $196.22. That was FAR more than I wanted to pay, but I got a great full-sized car battery that fits great and has a superior warranty. Now I don't have to worry if I'll ever get stranded because of a small, cheap battery that I would probably replace a lot more often than I'd like.

    This "Prius" battery has 390 cranking amps, 325 cold cranking amps and is the same width and height as my old Japanese OEM battery, however it is 2" longer. In my Hijet and Atrai vans, the battery well was long enough to fit the 2" longer Prius battery. FYI, the Duracell battery dimensions are: 9.38”L x 5” W x 8.87” H. (For additional size options, search for Group 51R and Group 151R batteries.)

    I just thought I'd post this to possibly help someone else wanting an alternative to buying a garden tractor battery. My 30 year old van is so incredibly nice, I thought the much higher cost of a quality car battery was worth it. YMMV.
    Duracell.jpg Battery.JPG
  2. Chrisv

    Chrisv New Member

    I replaced mine as well with a Prius battery from NAPA. Easy install fit right in my box. $200.00 buys a lot of piece of mind to me!

    DAN CANAAN New Member

    U1 tractor batteries are popular replacements too, with more than double the OEM specs for cranking amps. I've only had my HA4 for coming up on a month, but I have been surprised at how well the OEM battery is at popping off that motor. That said, I would be tempted to go with a higher capacity battery as well.

    Another mod I have thought about is a second alternator. As AC was an option but not equipped, there is a space for another alternator in place of the AC compressor. Self exciting 12 volt 63-100A alternators are inexpensive for after market use and it would not be terribly difficult to rig it up. I only plan on adding LED lighting and a winch, but running out of power is always a factor to consider in your planning if it is an option.
  4. Jigs-n-fixtures

    Jigs-n-fixtures Well-Known Member

    Why not increase the output of your stock alternator? On my Hijet, I found that I could get the Mini-Denso pattern in up to 130-amp outputs.

    DAN CANAAN New Member

    Curious what you found, and hopefully not $300+ that I see out there.
  6. Jigs-n-fixtures

    Jigs-n-fixtures Well-Known Member

    Measure the space you have. Form there you can go online and search for, “automotive battery sizes”, or “lead acid battery sizes”.

    that will give you some sites with tables you can go through and find a battery which will fit in your space. On my Hijet I found that I could fit a group 35/75 battery. It has about thre times the CCA of the stock battery, and about 2..5 times the reserve capacity.
  7. t_g_farrell

    t_g_farrell Active Member

    I put a EverStart 51 in my van, its was a pefect fit but I had to get some jdm to sae converters for the post (on amazon) and it has 500+ CCA which is perfect. Can crank as long as needed and the alternator hardly runs at all. Got it at Wlly mart for $129.00 out the door exchanging the old batter.

    Limestone likes this.
  8. matt167

    matt167 Active Member

    When I had my Jimny, I put a Die Hard Gold U1 which had a good warranty and iirc it was 500 CCA. Just rigged it up with pencil post adapters and it was dead reliable. I think it cost me $70 and was the same size as the original battery.

    The Prius battery is $200 because it's AGM and a specialized battery. There is really no need for an AGM battery with a ton of reserve capacity to spin over a 660cc engine even if you have a boom boom stereo or something.

    The Prius 12v systems run off battery power while the engine is not running. This runs the battery between a state of charge and discharge constantly, which is why they need the AGM battery. They are actually designed with a higher reserve capacity/ deep cycle abilities like a marine battery. That is why the battery is limited on CCA, even though I know for a fact that 160cca will spin over an F6A without issue

Share This Page