main Question: I have a 04 automatic g35 coupe. I

Also, is there anything i need to know while replacing my battery.
Any brand recommendations to purchase for new battery?

Right now I got my friends battery to test with and make sure he problem is battery and not alternator or perhaps something else. The tester battery is a Optima redtop Model:3478DT. I think its for his van.

My story on why i need a battery: yesterday my car did not start, I tried to turn it on but it kept making clicking noises. I got a jump start and it started immediately. I went to work(18 miles) and parked it. For security i tried to start it and it started twice, ofcourse this was right after i parked it and drove it. After work it did not start, making clicking noises, i got a jump and in less then 30 seconds it started. Came home, parked it, and my bro said he jump started it in less then then 10 secs. Im guessing its the battery. The car is about 4.5 years old. How can we distinguish whether it is the alternator, battery or starter?

 

The battery is a little tougher than most to remove because it's in a weird spot without much room around it to get your hands in. You'll need a mid-sized flathead screwdriver to get those plastic screws out. I think there are 5 of them that hold the black plastic around the battery in place.

-Remove the battery cover and set it aside.
-Using your flathead screwdriver, stick the sharp end of it under the head of the black plastic pop rivets one at a time and pop them upward. Remove each rivet and place it somewhere that is out of the way so you don't lose them.
-Once all the rivets are out, ou should be able to just lift the plastic battery cover frame straight up. You may have to pull aside some of the rubber seals around it in order to do this.
-Once the black plastic is removed, use a small ratchet with the appropriately sized(not sure what size) socket to loosen the bolt on each of the battery terminals.
-Pull the battery terminals off of the battery.... typically you would remove the black(ground) wire first for safety reasons, followed by the red(power) wire. Be sure to pull them out of the way or tuck them under somewhere so they aren't in the way for when you go to physically remove the battery from the fairly restrictive spot that it is located in. I usually take the positive side(red with a big electronic cluster attached to it) cable and lift the entire assembly up and out from the metal chassis frame of the car by about 2 inches(there's a rubber seal that holds it into the frame, which will release when you pull up on it), and then I tuck the entire piece in on the other side of the frame, so it frees up more space to move my hands in there while trying to grasp at the battery.
-Using your ratchet, loosen the bolt for the battery mounting bracket and then push down on the bracket until it becomes unhooked from the battery tray.
-loosen the bolt on the rear side of the battery mounting bracket and unhook that from the vehicle's chassis and pull the entire mounting bracket and both hooks out from the car and set it aside.
-Now you shoudl be able to just reach in and lift the battery out. Be careful not to cut your hands up too bad on the parts surrounding the battery, because it's pretty tight in there. You'll most likely have to tilt the battery towards the front of the car in order to get a hand under it and be able to lift it out. Be careful not to drop the battery on the car while you're lifting it out, since you probably won't have the best positioning on the battery with your hands at first when you get it out of the car.

Installation of the new battery is the reverse of the removal process.


Optima makes a great battery, but they're very expensive. They also tend to be significantly lighter than a regular battery... which is an added bonus.

 

Wow thank you for your insturctions! It really is a tight fit in their. The power cable(postitive) is most in the way. Im afraid i might break it, but those instructions give me a sense of security. I will let you all know what happens with my car.

 

Many places that sell batteries will load test your old battery to see how it's doing. Always a good idea before you replace a perfectly good battery.

 

keep your buddy's redtop Optima

 

^j/k....terminals will be backwards and won't fit anyway. Optima is a very good battery though.

 

An optima will fit, it is just a PIA to do and I had to swap out the negative battery termial for a longer one to reach, but I am running a Optima yellow top...

 

Optima with reverse posts FTW.

 

I have one with the regular posts on it, that is why it was a PIA...

 

man.... .I just changed out my battery today. such a pita with the mounting brackets!

 

^Same, my battery died yesterday and it was b!tch to replace....

I got Durust?...battery.

 

Likely '04 battery is due and not your alternator but you can go to any autozone to make sure. I installed the Optima Redtop with reverse posts. I think its 25R but check out the Optima site. It came with a tray insert that raised the battery and made replacement simple. Just take off the upper cover-surround like indicated above and you'll have no problems. Don't overtighten the posts or the top battery brace. I don't think it was any lighter than stock battery but it does have more crank and reserve power.

A bit more expensive but cheaper than getting stuck in the middle of nowhere...

 

i never looked at the battery since i havent had any trouble with it yet ..

but damn took a look at it just now. .. its tight in there lol..

 

If you keep vehicle long enough you will get a precise feel for exact battery life.

My 19.5 year old Q45 eats batteries every 36 +- 2 months in Atlanta. Battery #6 was installed in June 2008. Becoming ONE with the vehicle will occur eventually.

 

Here is a DYI I did a while back:

https://g35driver.com/forums/g35-sed...ce-optima.html