By Don Paul
October 2, 2021
I just replaced our 8 year old original Mercedes (Varta) chassis battery in our 11VK with a $149.76 Platinum EverStart H8 AGM 5-year warranty battery from Walmart and learned a several things… So I’m posting a STEP-BY-STEP installation procedure to save others time & frustration:
- Walmart’s website shows “This item does not fit your 2011 Mercedes-Benz Sprinter 3500″… but it is WRONG. It fits perfectly. What’s really wonky is when you click their “Find Items that fit” link it shows their EverStart Maxx LEAD ACID (non-AGM) batteries “fit”… but these lead acid batteries NEED open air venting which our Sprinter’s battery compartments don’t have. DUH. They’ve got it BACKWARDS… Our V/Ns need AGM batteries !!!
- SAVE YOUR RECEIPT !!! You’ll need it if you have a warranty claim. I suggest taking a picture of your receipt and saving it on your phone… AND taping the receipt completely covered in clear packing tape to your battery compartment lid where you’ll be able to find it years from now IF you need it.
- Extracting the existing battery was a bit tricky since the positive cable/terminal has a bank of fuses attached to it which took some doing to finesse this fuse bank out of the way to get the existing battery out. YouTube video helped
- WAIT 10 to 30 minutes after you’ve turned your Sprinter OFF and removed the key to prevent getting a CEL (“Check Engine Light”) after you’ve installed your new battery
- Disconnect your chassis battery from the Sprinter chassis by pulling the plug next to the accelerator pedal. ALL your chassis lights should go out.
- Remove the (3) T25 bolts holding down the plastic L-shaped piece with a battery icon stamped on top. Don’t drop the bolts on the ground… You may never find them again.
- Remove the molded grey rubber floor mat. Yes it can get hung up but it does just pull out
- Loosen (no need to remove) the (4) Torx bolts (T25) holding down the metal lid of the battery compartment. Slide it aft to remove the lid.
- Remove the Red plastic cover over the Positive (+) battery terminal
- Loosen the 10mm nut on the Negative (-) terminal and remove the cable from the terminal. You may need to twist the cable to get is “unstuck” from the battery terminal.
- Unplug the existing AGM battery vent from the front of the battery. It just pops right out.
- Locate the black plastic handle for the battery hold down at the front of the battery bay. PAY ATTENTION TO WHICH WAY IT IS ORIENTED so you know which way it goes back in. (50% chance of re-inserting it incorrectly = 100% frustration… Think USB plug insertion frustration)
- Remove the battery hold down by completely loosening the bolts from their threaded sockets. The bolts should stay in the battery hold down. I needed a ~ 10″ extension on my 10mm socket and task lighting to remove the 2 battery bolts at the bottom front of the dark battery compartment. They came out easily and pulling the handle for the hold down lifts it up and out of the way with the bolts attached.
- Remove both the Positive (+) cable from the battery post by loosening the 10mm nut on each hold down, then twisting the battery cables up… and move them out of the way of your battery.
- Push the old battery forward FIRST to remove it since there’s a fixed hold down on bottom the aft part of the battery compartment. Again hard to see since this compartment has Black parts on Black compartment with poor natural light (chassis lights are off because the battery is dead / disconnected)
- You need to be flexible and strong to remove the ~ 60 lb. battery since the steering wheel is above the battery and the driver’s seat & base are in the way too. I’m 64 years young and fit (thanks mountain biking) so not a problem for me… but others may want to have Walmart or someone else install it for you. Walmart will probably charge since this installation is another Mercedes over-engineered PITA that takes time AND skill. IF you have someone else install it, be SURE they put the Red plastic plug in the aft vent hole (see below)
- Remove the new new battery’s Black plastic cap from the Negative (-) terminal and the Red plastic cover from the Positive (+) terminal. DON’T TOSS THE RED COVER AWAY… it has a small Red plastic plug you need to insert in the vent hole in the aft (+) end of the battery. This isn’t obvious unless you RTFM which is a TINY 1″x1″ yellow square taped to the side of the battery with print so tiny you’ll need a magnifier to literally “read the fine print”. LOVE my iPhone’s built-in Magnifier feature for tasks like this!
- Lower the new battery into the compartment. Mine wasn’t easy doing it solo since the vent tube kept flopping into the battery compartment in the front BELOW the battery as did the fuse block on the Positive cable in the back. Helpful to have another set of hands or secure these out of the way before inserting the battery… or Yoga move to tip the battery in the hole with one hand then grab the vent tube with the other while lowering the battery in. Who needs a Yoga workout or lift weights when Mercedes provided a Home Workout ??? LOL
- Move the battery forward to connect the Positive terminal / fuse bank.
- Push the battery aft to insert it under the fixed aft battery hold down.
- Reattach the Red Mercedes (not EverStart battery) plastic cover over the Positive (+) terminal / cables
- Connect the vent tube to the vent hole at the center of the forward (Negative terminal) side of the battery. Confirm the tiny Red plug is still in place on the aft (Positive terminal) side of the battery.
- Reinstall the battery hold down by FIRST finding the 2 battery hold down bolt holes and the centering gizmo at the bottom of the dark battery compartment. Then lower the hold down bracket into the compartment lining up the bolts with the black bolt holes on the floor of the poorly lit black battery compartment. Yoga helps since the driver’s seat base has a sharp corner which loves to poke ribs (I have a bruise to prove it LOL). Hand tighten the hold down bolts… and check your new battery won’t move
- Reattach the Negative (-) terminal.
- Recheck BOTH the Negative (-) and Positive (+) terminals are securely attached. Re-tighten just to be sure… You’re connecting a powerful 900 CCA diesel battery !!!
- Reconnect the Negative battery cable to the terminal by the accelerator pedal. Your Sprinter should lights come on. WINNING !!!
- Replace the metal battery cover by sliding the holes over bolts… then pushing it forward so the bolt heads are above the bolt slots. You may need to move the black (+) and red (-) cables to get it to go back on smoothly. Check to make sure none of your battery / chassis cables are going to be crimped when you tighten the Torx bolts to the cover.
- Replace the grey rubber floor mat. You may need to push it forward to get it to fit correctly in the back so you can…
- Replace the L-shaped piece with a battery icon stamped on top and reinsert the (3) T25 bolts holding it down. Don’t drop the bolts on the ground… You may never find them again.
- Celebrate / Medicate for a job well done.
HOPEFULLY I didn’t leave any steps out… and I make no representations that I didn’t AND/OR these are the same steps you need to replace your Sprinter’s chassis battery. YMMV. If you’re not sure have a professional install it for you.