2002 Gem car batteries

I just bought a 2002 E825 Gem car from a friend of mine. He had put Xtreme group 31 marine batteries from batteries plus and he let some of them go bad. He works out of town and did not check them.

I was wondering which battery would be better the Napa 8271 which is a group 27 or the Napa 8272 a group 31. The 8272 or only $20.00 more a battery than the 8271. I didn’t know if the group number made a difference. I think I definitely want gel batteries because I work out of town as well.

Any information would be helpful,



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Andy, the Group 27 is a much smaller battery than Group 31. Unfortunately, when a couple of batteries go bad due to neglect, the rest are sure to follow. In a series arrangement, unless the battery fails when nearly new, you must replace all 6 at once with identical new batteries. The only exception is if you hve identical batteries of the same age range as the bad ones from the car you can use as replacements.

Replacing one or two batteries while leaving the other, old batteries, in the string will cause the older ones to fail very quickly as the new ones will have higher capacity than the old ones and over-power the older neglected ones.

Gel batteries are nice if you can afford them and have the right charging profile selected on the Zivan charger but, once again, you must replace them all at once. Deka (made by Penn Battery) is the recommended gel battery for your GEM. According to our resident guru (Gem_Mechanic) NAPA has the identical OEM gel battery as NAPA part number 8272 (Group 31) or P/N 8271 (group 27). A gel battery may be more-deeply discharged than a flooded-cell in some cases so you may get better range with them but it’s not going to be an easy pill to swallow. The NAPA 272 cost over $300 apiece here in New England.

OEM Trojan T1275 flooded cell batteries are a good choice but you’ll have to check the water and add every few hundred miles or few weeks. They routinely go for between $200 and $300 apiece. I would imaging the OEM gel batteries are even more expensive. You might try a battery distributor and look for Industrial deep-cycle or Motive-Power batteries in Group 31 or Group 30H.

Let the weight of each individual battery be your guide. More lead = more life in these heavy draw applications. An OEM Trojan T1275 weighs almost 90 lbs. while a Group-27 typically weighs under 70 lbs.

You get what you pay for. Personally, I used Group-31 marine deep-cycle batteries and get a reduced range on my 2002 Gem eL. I installed a battery monitor meter and calculated that I get only about 70 amp-hours of useful range before the batteries just can’t produce adequate voltage/current anymore to drive full speed or up the hills we have here at over a crawl. Better (more expensive) batteries might get me another 20% more range. Right now I’m limited to about 20-22 miles driven normally. Your range may vary with terrain and driving style.

Lifetime is another trade-off you’ll have to make with cheaper battery alternatives. I expect I’ll be replacing these $110 (each) batteries in 2 or 3 seasons. Those $275 T-1275’s are starting to look better all the time :frowning:

Thanks for the info Bob. I can’t afford the gel batteries right now nor the Trojans so I figured I would try to charge the ones it came with individually. After charging them individually and adding some water the zivan charger kicked on. I was able to take her for a spin but not very far, two loops around the neighborhood to be exact.

I checked the batteries with a tester and only one was bad. I had a hot marine battery for my boat so I traded it out with the bad one. When I got a 100% charge I took her out again and got up to 39 mph on a straight away in my neighborhood and it felt like 85 mph ha. I know I’m still going to have to purchase new batteries but I am very excited to know that is all is wrong with it mechanically. Now I got to find some new mirror brackets and another lock for the glove box.

I think I’m going to enjoy this little car. I couldn’t have done what I did this weekend without this forum. Thank You and everyone else on this forum for the help and knowledge.


Wow - 39 MPH is FAST in a Gem; especially in the 2002 with its crude suspension and steering. The motor and controller can’t possibly be stock - that’s for sure.

What are the batteries that are in the cart? If they’re the same group (27 or 31) as the trolling motor battery you put in, you could be in pretty good shape. You shouldn’t mix & match battery types, sizes or ages though. It’s hard to keep a string of batteries balanced anyway and adding different sizes or age batteries will only make it worse.

The one I put in is a Group 27 and the rest are 31’s. I just wanted to see what it would do. I turned the master switch off yesterday. I figure the Xtreme batteries will be back down again by the time I get home Thursday.

I am planning on buying a new set of the Napa gels group 31 when I get some cash saved up. I thought about buying another group 31 until I can afford all six new ones. I’ll put a load tester on the other 5 and see if they are still showing good. What are your thoughts on that? I mainly just wanted to make sure I didn’t need a new charger or have any other problems the lights, horn and signals all work, which is a good thing.

As far as the motor and controller not being stock I’m sure they are not because the guy I bought it from said it would do 45 mph. It does have the 14" tires so it could not be a true reading. Do you know how fast one should go in turf mode because I think it said 23 mph which I thought was too fast? I even told my wife not to ever drive in Highway mode because I thought it was a bit fast especially taking a curve. Your right about suspension and steering it reminded me of some old muscle cars that I used to have with fast motors and terrible brakes and steering ha.

Thanks again for the input.


An '02 should have the GE T-2 controller which can be programmed for larger tire size and/or different gearing (unlike newer ones). I suspect you have an upgraded motor and reprogrammed controller as a stock GEM only goes 25 MPH on level ground. You may want to check it with a GPS t see if it’s way off.

The controller can be reprogrammed for higher top speed limits but you can only get so much speed with stock gearing due to the design limits of the GE 5HP motor. Mine goes about 30 MPH on level ground with fresh batteries and stock gearing but upgraded tires & wheels.

Check the DC converter on the right side under the dash. If it’s an open-frame design with an exposed circuit board it’s a ticking time bomb that will eventually fail on you. The original manufacturer (SPS Electronics) makes a fully-potted model that will outlast the rest of the car with luck but they’re not exactly cheap ($350 or so).

Look at the front CV joints and check for grease leaking out of them at the folds in the bellows. The CV boots are available fairly cheaply for these. Check the rubber suspension bushings for play. They get compressed and cause rattles and knocks.

Enjoy the heck out of it. It sounds like you got a good one that just needs some TLC to bring it back to its original glory.

Thanks, I got a price from a local guy at home that sales Trojan batteries. I told him what I had he said he had brand new Trojans for $175 a piece but I don’t know if they are the 1275’s yet didn’t know what I needed at the time. If they are I may jump on them. Where can you find one of those battery refillers or what or they called exactly? Thanks for the help

I use a squeeze-bulb type filler I got from a local auto-parts store and a plastic hydrometer to measure the battery’s specific gravity. A glass hydrometer with an integral thermometer is better but I broke two of them so far so deal with the cheap plastic one with the plastic tilting gauge. It’s hardly accurate but it will tell you if a battery is having a problem with one or more cells.

Thanks Bob, I been doing some serious research on batteries. Sears has a Die hard Group marine batteries with a 3 year free replacement warranty huh something to think about.

Andy, I have a 2002 two seater as well and it has the 7 hp motor in it. It will do 38 mph on flat ground. I used marine batteries but never got anywhere near the 35 mile range touted by GEM or any of the other forum members. I finally bought Trojan T1275’s and now I have almost the total range promised by GEM. When I went to trade in the old marine batteries I had to pay them $30 per battery because of the lack of lead in the marine batteries. He told me that the marine or any type of auto battery were simply not designed to operate a large motor and expect them to provide the same power below about 60% charge. I can vouch for that because I would have my car stop but still be showing 68% charge. Now with the Trojans I can go down into the 40% range and still have full speed. Lift any new battery that you may be considering and then lift a Trojan or similar battery and you can tell immediately whether or not it has the same amount of lead in it. There is no substitute for lead in a wet battery. Enjoy your new car.

I just found out that I can get the T-1275 here locally for $175.00 (with core). It’s possible if you shop around locally you might find such good deals. I am planning to go with them also, if I find out that my Zivan charger will be able to handle them. They are 150Ah vs. just 130Ah with the Trojan 30XHS OEM battery.

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Lifetime is another trade-off you’ll have to make with cheaper battery alternatives. I expect I’ll be replacing these $110 (each) batteries in 2 or 3 seasons. Those $275 T-1275’s are starting to look better all the time :([/quote]

Was your Zivan charger able to properly and fully charge the T1275 batteries?