I looked around some and could not find a thread on this, if there is one, can someone redirect me please. thanks.

Anyhow, looks like the battery is shot, was able to get the seat forward on the passenger side and pull the plastic cover off, so I can actually see part of it. removing it didn't seem straight forward so I stopped at that point and wanted to get more info.

Any help appreciated!!!

 

If you have your owners manual there are pictures and instructions in there of how to do it. It's a combination of moving the seat forward and back, cutting the carpet, etc.

You can get an on-line version of the owner's manual here:

http://www.mbusa.com/mercedes/servic...owners_manuals

 

When my battery went out, I called roadside service and they came to the house and replaced it for only the price of the battery (no labor charge). Took them about an hour and cost around $300 for the battery since my GL was out of warranty.

 

Good advice! I had battery issues on my 07 but nothing on the 11!

 

I just swapped out the battery in my '07 GL.

The instructions in the owner's manual are very clear, and nothing is omitted.

When you are pulling out the old battery, note that the OEM unit has two little handles at the top. Makes it easier to pick up.

The terminal nuts are 10mm; the holddown clamp is fastened with 13mm nuts.

Disconnect the negative terminal first.

The only advice I would add to the instructions is regarding the corrosion that develops on the terminals.

Stand by with a vacuum cleaner and suck up the fuzzy gunk from the (in my case negative only) terminal. Clean the terminal connector after you remove the old battery. I rinsed mine into a little bowl I placed inside the battery compartment.

Grease up the terminals with lithium grease. After installing, I also sprayed the terminal connectors with lithium grease spray. Both of these items are available at Wal-Mart. The OEM installation was greased on the positive terminal, but not the negative, and the positive was corrosion free but not so the negative.

I proceeded slowly and carefully, even though I am a fairly experienced mechanic, because I like to do battery replacements right. I cleaned out the compartment thoroughly, which no AAA mechanic will do in a parking lot, and I frankly doubt even the dealership will do.

I bought the battery at Pep Boys. It is Bosch branded, but that battery, and most others you buy retail, are made by Johnson Controls. Pep Boys had an online ordering discount of 15%, and my total cost with tax (less the core charge) was $105. I figure it was about $100 - $200 savings for about an hour's work.

Oh, and I reused the OEM red plastic cover for the positive terminal, and put the replacement battery's black plastic cover on the negative terminal. Now I have both terminals covered and I am happy.

 

I took my gl in to have the brakes replaced and they did an all around test and indicated my batter was at marginal. They wanted almost $300 (none dealer of course) plus installation...
Decided I can do this myself. Funny I had to get the owners manual out to find out where it was located. Talking about hiding a battery. I've only owned this vehicle about 8 months and it's been fantastic. Haven owned several benz in the past they can get pricey if you don't shop around.

In any event I followed your advice Eric and it was a breeze. Pep boys carried two batteries, I elected to go for the AGM which was about $100 more but I like to keep my cars as close to spec if I use aftermarket items. I taped some plastic down with duct tape so nothing would get on the carpet and with a little work I got it out and change. I'm like you Eric I like things nice and clean and put some grease like you recommended.

 

Two questions.

1. Should the small accessory battery also be replaced at the same time as the main battery?

2. Does the vehicle need to be reprogrammed for a new battery after the install? I know in BMW's you have to.

 

1. No
2. As long as you maintain voltage on the system with a charger (via the jumper connections under the hood) no adaption is necessary. If you don't keep jumpers on during the evolution, some of the data in the COMAND system (all stored addresses etc) WILL go away.

 

Thanks for the reply. I will connect a Battery Tender to the battery clamps when I install the new battery.

 

I'm planning to replace the original battery in my '08 GL450 (now 5 years old) which is beginning to sound a bit weak and not cranking the engine with quite the same vigor it used to.

Question on the battery charger/tender on the under-hood jump terminals; if I place a battery charger on these terminals to keep the electronics powered while I'm replacing the battery will the positive lead in the battery compartment become hot? I.e. will I need to be careful not to ground it?

I'm planning on going with either the Sears DieHard Advanced Gold AGM, or the similar O'Reilly Super Start for about $170. Are these decent replacement brands?

I assume these batteries will be fitted with the vent hose connector for venting externally, and that I should make sure they indeed are when I purchase it?

 

I just replaced mine with the Sears DieHard Gold battery. Same specs, size, and vent. Nice 3 year warranty too. I hooked a Battery Tender to the battery clamps under the passenger seat during removal. Reinserting the battery into the compartment was a very tight squeeze and the Tender clamps had to be removed for @5 minutes. After reconnecting the battery clamps, I found the COMMAND data was not lost. I only had to reset the windows, folding mirrors, and sunroof per instructions in the manual.

 

You would need to be careful. I would follow the instructions and not deviate from them. Resetting the windows is not that hard, and there's a chance you will really cost yourself a lot by hooking up the leads wrong, shorting them against the frame, causing a sudden voltage surge ... no way would I do it.
Usually the batteries are delivered complete.

There are only a few battery makers. I don't think you can go far wrong.

 

Sam's Club or Walmart H8-AGM batteries are $160 but the $15 'core charge' will be refunded when you take in the old battery......Total cost will then be $145. The main battery must be removed to access the aux battery. They cost either side of $20. Since they are the same type of AGM battery as the main battery and have about the same life expectancy I think it's worth the $20 to replace it as well rather than having to remove the main battery again down the road to replace the aux battery..........

 

I'm planning to buy one from Auto zone the Duralast Gold/Battery. I'm not really a mechanic and do not have much experience with cars. Should I get it installed from them? I went to the dealer and they are asking $720 for both batteries.


- Where can I find and buy the auxiliary battery?
- Is there a installation guide for that as well?

 

I'd get it installed at an independent mechanic. You should get yourself an independent mechanic anyway. I would also let them get the battery for you. You won't pay much more than from Autozone, and they will like procuring the battery themselves. One less variable.

 

What he said.

But also ask the dealer to detail out the costs, and then start laughing at him.


$720, he should be ashamed!!!!!!!!

 

Thanks I go back tomorrow to pick up the car. I've told them to hold off on the battery.

 

Battery took me about 10-12 mins to replace in -30C weather (not sure what that is in Fahrenheit but I think it's about the same... either way it's COLD).

Battery had died on driveway in the middle of winter.. coldest day of the year. And it was 7pm so it was really cold and dark out.

Got a "headlight" (one that straps on your head) and a pair of gloves. Was done in about 10 mins including cutting the carpeting. I was working really fast due to the cold though... would have taken me 20 mins on a regular day.

Not hard at all. Follow the directions in the owners manual. Seat has to be moved back, then forward.

Nothing gets lost when battery disconnected, except for window and sunroof adaptations. All COMAND settings, functions, memories stay just fine.

To reset adaptations it's quite easy. You usually open the window (or sunroof) and then close it by pushing the button to the first click position (don't press it hard so it 'auto-closes' if you know what I mean). Once it is shut, push the button down harder (to the 2nd position) and hold for 10-15 seconds.

Then open the window and push the button down hard to the 2nd position. If it closes all the way and doesn't reverse and open again, all is good. You are just telling the window where the "fully closed" position is. Remember these windows need to know where closed is, because up to that point if they hit resistance they'll reopen (assuming they hit a finger or arm sticking out the window)

Sunroof is the same.

Cutting carpet is easy.. there is a perforated line already. Just use a utility knife and done in 2 mins.

I bought a Walmart H8 (1000 cold cranking amps) and it's just as good as the MB battery. It has been about 18 months since replacment (including 1 full Canadian winter) and starts up perfectly fine.

Not sure if it will last 7 years but I might just replace it in 4 winters.. for the $1xx.00 I paid for it, it's totally a great deal.

Note that these batteries die almost exactly 7 years from the manufacture date of the truck. So the '07s should have all had batteries replaced by now, '08s were last winter and this upcoming winter, and '09's should be replaced next spring before the following winter.

If you have an 07 or an 08 replace your battery NOW if it's original. My truck cranked perfectly fine one day and the next morning was dead as a doornail. Gave no warning at all.. it just quit!

 

^ good post. Mine is an 08 and I will put this on the list of maintenance to do before winter. Also, I've experienced -30C winter before and it is properly COLD. Would not have been able to do any work in that temp. Hat off to you.

 

All good, except the battery life.
Ambient temperature is a BIG factor with hot weather shortening the life of batteries and cold temps extending them.

 

I took my truck to the dealer and it took them 3 hours to install the new battery. Glad I didn't try to DYI; if it took them 3 hours, how long would it have taken me?

 

1 hour.

 

They must have taken a 2 hour break. No reason it should take that long with the stock MB battery.

 

They took 3 hours to justify the $720!

 

They charged you 3 hours or it took them 3 hours? Two different things.


They could have charged you the book rate, which probably includes unbolting and removing the seat, cutting the carpet, and installing the battery then running a battery test.


In reality the tech probably moved the seat forward and back as required in the manual, cut the carpet and swapped the battery, then drove it back out of the shop. That could only take 1hr at the absolute most if it's his first time doing it!


I had never done one before, had the tools ready (handful of sockets, socket wrench, box cutter, etc.) and was able to rush it in 10 mins. And all I had done was read the owners manual first. Memorized the steps then went and did it.. didn't have any manuals in front of me.


I would be surprised if it took them 30 mins and I'm sure they charge the full 3hours. Plus full retail price on the battery I'm sure.


What did the total come to including the battery and labour? Just wondering