2018 GLS450 Check Transmission Fluid
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Joined: Aug 2022
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2018 GLS450
2018 GLS450 Check Transmission Fluid
I have googled extensively and searhed this site.
How do I check the transmission fluid in a 2018 GLS? I'm having some slippage in lower gears when leaving from a rest. I'm thinking the fluid level is low.
Car has 44,000 miles. Warranty has expired.
Much thanks for any advice.
How do I check the transmission fluid in a 2018 GLS? I'm having some slippage in lower gears when leaving from a rest. I'm thinking the fluid level is low.
Car has 44,000 miles. Warranty has expired.
Much thanks for any advice.
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From: New Hampsha
'17 GLS450, '14 GLK250, Grandpa's Roadster
If it's not leaking you can pretty much bank on the fluid level being ok. The way to check it is to run the engine until the trans temp reaches a prescribed level (maybe 60 degrees C, but don't quote me). Then, remove the level plug on the bottom of the pan, with the engine running. If you get any dripping then the level is OK. If nothing comes out, you can try pumping some in (there is no fill hole) and then let the excess drain out.
If the trans is slipping there should be diagnostic codes stored. Check them. In desperation, you can do a fluid change (not due until 60K miles) but at 44K I doubt if it will cure anything.
Can you say "Extended Warranty"?
If the trans is slipping there should be diagnostic codes stored. Check them. In desperation, you can do a fluid change (not due until 60K miles) but at 44K I doubt if it will cure anything.
Can you say "Extended Warranty"?
Thread Starter
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2018 GLS450
I may have not described the problem accurately, it is just poor shifting D2-D3-D4. I am going to try the reset procedure ... (Ign ON, gas all the way down for 30 sec, key off, release pedal, wait 2 minutes, start car and drive it for 15 minutes) which should reset the adaptive shifting points. I hope.
Thank you!
Thank you!
Thread Starter
Junior Member
Joined: Aug 2022
Posts: 21
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2018 GLS450
Reset procedure worked! Here it is for anyone else having similar problem.
During this procedure, do not touch anything in the car. Don't fiddle with the radio, etc. Do nothing but the steps below.
Also, if keyless go, remove the button and use the key.
During this procedure, do not touch anything in the car. Don't fiddle with the radio, etc. Do nothing but the steps below.
Also, if keyless go, remove the button and use the key.
- Turn the key to position II (run). Do not start the engine.
- Press the throttle to the floor. Activate the kickdown switch.
- Keep the gas pedal pressed for 30 seconds. Hold to step 5.
- Turn key to OFF, position 0. Do not remove the key.
- Release the gas pedal.
- Wait 2 minutes. During this process, key is left in the ignition in the OFF position.
- Start the car and drive for 15 minutes.
