when should we change the trans and diff oil? How much is reasonable cost?
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Junior Member
Joined: May 2021
Posts: 22
Likes: 5
2009 gl550
when should we change the trans and diff oil? How much is reasonable cost?
just bought the 2009 gl550 83k miles. amazing maching. however needed new door actuator and front right suspension drops to ground when off (never saw that what i bought it!)
should i be get the trans fluid and diff fluid done too? what mileage? wait till 100k miles?
should i be get the trans fluid and diff fluid done too? what mileage? wait till 100k miles?
MBWorld Fanatic!
Joined: Jan 2010
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NGL450 w/EORP, S550
Trans fluid every 40k, diff fluid is an easy DIY.
But do not ignore your leaking air suspension.
Thread Starter
Junior Member
Joined: May 2021
Posts: 22
Likes: 5
2009 gl550
part ordered. and not driving until its changed. btw very reputable indy told me not worth doing other side. just do the broken one and we can do other one when it fails. he said it could be months or even years, why spend the money to do it now.
Super Member
Joined: Jan 2007
Posts: 622
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From: CA
11 ML550, 95 Supra TT, 14 Audi S4
I'd guess a shop would charge 2-3 hours of labor + cost of the fluid. The trans fluid isn't cheap. I paid $400ish the last time the dealer did the trans, but that was 5-6 years ago. Don't forget to change the transfer case fluid too.
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NGL450 w/EORP, S550
Pressurized air has a way of finding the easiest way out through the path of least resistance, which would be an older air bag with small tears and pinholes.
Since you have a 550 with ADS it is worth checking both struts and reusing them if there are no fluid leaks, and then replacing the air bags onto your existing struts.
If you have leaky shocks, look up bilstein or arnott rebuilt ADS struts that come with the airbag already installed - massive labor saver, but higher parts cost.
Having the car in only once to do that will save you labor in the long run.
If the rear bags are suspect change those too. That's about $350 and 15 minutes a side as a DIY.
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2008 GL320CDI (310k) & 2017 GLS450 (160k)
I changed mine 100k after the first trans fluid change and after 80k did the second time. Both times fluid looked clean. Diff fluid looked like it didn't need to be changed at all, I could not really tell the difference between new and old fluid. But I suggest you change transfer case fluid every third oil change.
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Member
Joined: Nov 2018
Posts: 139
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From: Portland, OR
GL320 CDI
Definitely get the trans and torque converter drained and a new filter. Again, it's basic maintenance that you should perform in order to get the truck baselined.
Senior Member
Joined: May 2013
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From: Espoo, Finland
2012 GL 350
Trans fluid every 40k miles. The fluid in the 722.9 transmission is about $100 and then you have filters, etc. It's not a terrible job, but many suggest taking it to a shop. I've done the job twice and it's no big deal, just a bit tedious. I do diffs at the same time. They're only about a liter of fluid each and I'd guess they'd charge you 30-60 minutes time for each.
I always change air suspension components in pairs but I once replaced the fronts only to have the rears fail two weeks later....they basically fail on time. I replaced with Arnott which have lifetime guarantee.
I always change air suspension components in pairs but I once replaced the fronts only to have the rears fail two weeks later....they basically fail on time. I replaced with Arnott which have lifetime guarantee.
