highlandlimo

I was in for my last schedule A service and they recommended these two maintenance ideas as well as getting new engine air filters.

The transmission has never been serviced so I think I might do that. Also the air filters. The spark plugs I'm not so sure about.

Any thoughts are appreciated.

Thanks!

chassis

Yes to all of it. Plugs and transmission service are specified by MB prior to your mileage. Use the search feature on this site and you will find the maintenance intervals for your vehicle.

The transmission is not flushed. It is drained, a new filter is installed, then refilled. No flush.

Best practice is to follow the MB schedule.

sub786sub

Here is how to do an Oil change, AT, Coolant flush, and Spark Plug. This video is for C class but the same engine as GLE 350, 2019, and earlier and should apply. I will go for sparkplug too regardless of the recommended service as if you do all those things as preventative it will be good for the next 75 K miles

amusa

I been trying to do the Trans fluid/filter for month now. I have the parts and planning to do it sometime this month.

If your going to do the Air Filter why not do the cabin and dust filter while your at it? I would get the spark plugs done. I did mine back in June of 2021 with NGK Iridium around 55k miles on the odometer.

Did you do the front and rear diff fluid?

highlandlimo

I usually just do what they tell me. I am not a "car guy" or DIY-er so I'd rather have professionals do it if for nothing else than to give me piece of mind.

They haven't recommended anything except for the spark plugs, trans service and the engine air filter. Didn't mention anything about the diff fluids.

chassis

Axle differential fluid is not specified for replacement by MBAG. If you want it changed, which is good practice, you need to ask for it.

amusa

Just to clarify if someone is looking to do the Trans fluid flush or change themselves. You need to know if your W166 has Code A89 (Reduced Friction). The part's numbers are different and the Trans Fluid are different (Code A89 use the blue color) and non A89 use red color.

You can decode your VIN# on any free website and should tell you have you have Code A89.

I have talk to my friend over at MB he said usually they charge around $600usd for the blue color fluid for the Trans fluid service. Just giving you all a base number how much they would charge for parts/labor at Mercedes.

John Ha

I had my transmission service done at my dealer earlier this year (I have the A89 build code). It was about $460 with tax. My documentation (for 2016 GLE) indicates that this service needs to be done every 60,000 miles.

I've also changed the differential and transfer case fluids myself. It was really easy to do after finding the correct fluids. They're still expensive (~$100) but I probably saved a boatload not having to pay the dealer prices for the fluids and labor. There's a MOPAR transmission fluid that meets the spec for the transfer case and I got the differential lubricant from Pelican Parts.

John Ha

This was a pretty good video - thanks for posting it.

I was a little disappointed that it didn't show the ABS "exercising" that is supposed to be done as part of the brake bleeding process (or at least it is on mine). I don't remember whether that's integrated into the on-board software in the "Service" menu items or if an external tool is required to do it.

chassis

ABS exercising is not part of the WIS process, therefore no tool or menu required.

John Ha

You're right! I made a bad assumption - in other vehicles I've owned it was necessary to exercise the ABS during the brake flushing process - I assume so that the fluid in the ABS unit is thoroughly exchanged with fresh. My bad.

amusa

Just want to add 1 more thing. You need to replace all (6) Transmission oil pan bolts every time you drop the trans oil pan. The (6) bolts CAN'T be reused since there aluminum made (streetch bolt's). I just found out days ago. I had to order some bolts and do the 2 day shipping since my supplier is having a hard time getting parts. I'm changing out the Trans fluid next week. I got one of the lift reserved at the shop.

highlandlimo

Ok, so I did have everything they told me to do done.

Now, can someone tell me how important replacing the diff fluid is? and what the time frame on getting it replaced is? It probably gets 90 - 95% highway miles.

TIA

chassis

I changed axle (differential) fluid around 60k miles and it looked like new. 75k miles (now) is a good time to do it. MB does not specify axle oil change so dealers won't be much help with finding the right oil to use. Viscosity and part numbers are posted on this site. It's listed in my GLE Ownership Report thread, and the thread is indexed every page or so.