S Naqvi

I have a 2019 GLS 450 (90k), it's been at the dealer for nearly a month now because it automatically shifts to N moving from a P to either D or R. Initially, they charged me $800 for a new battery but that didn't resolve the issue. Now they are saying I might need a new transmission. I've been reading similar issues and most are telling me that it's a result of a fault TCM (I have codes). Has anyone experienced this before?

Thanks!

S Naqvi

So they came back saying they think the valve body needs to be replaced. It's a pretty expensive repair then let's the TCM. It's a 2017 GLS. What would you guys do?

John CC

I don't understand what you're describing as the problem. Do you mean you can't shift into D or R, and all you get is neutral?

Either way, if they say the valve body will fix it (make sure you get them to say that!), and it's on your dime to pay for it, then, if it doesn't, it should be on them to make good.

S Naqvi

After the car has warmed up and you've already driven it. Let's say your at the gas station and you have the car in park after you've completed pumping gas and ready to pull out you switch to D and as soon as you hit the gas the car switches to N. This happens in comfort mode. If switch to Sports mode or Manual if I shift from P to D1 it works fine. Same thing happens when going from D to R. It's intermittent it doesn't always happen.

The one time the check engine light came on the code was P0700.
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John CC

Has the transmission fluid ever been changed?

S Naqvi

​​​​ I was going to have it changed in my next service which is in July so the answer is no.

John CC

I'd do it now. It might solve the issue.

S Naqvi

They called and left a VM saying, the replacement of the valve body and transmission fluid for $5000.
In the past, they have quoted the transmission fluid change for $1300.

I'm not really confident in their techs because over a month and a new battery later they still don't know exactly what's wrong. But if I do fluid change and this doesn't resolve it, does a valve body replacement require another fluid change? I'd be paying twice then.

If the valve body needs changing, this is because they have found metal debris?

John CC

Find a good, independent shop. The fluid change shouldn't be anywhere near that much.

If they change the fluid in concert with the valve body it shouldn't be much more than the cost of the fluid. The fluid is coming out to get at the valve body. All they need to do extra is drain the torque converter and change the filter (again).

S Naqvi

Should I ask for a just a fluid and filter change or the full service?

BlownV8

2nd the idea to take it to a good independent and have them do it.

S Naqvi

This is what the dealership emailed me today, "We followed a guided test on the SDS scan tool that led to a problem with the valve body of the transmission, in other words the central command unit of the transmission. It controls when the transmission is supposed to shift and there is an internal fault. Replacing it would include a transmission oil change as well..." $5200

S Naqvi

I got it down from $5500 to 4000 to replace the valve body + transmission is that a good price?

John CC

I can't say if it's a good price, but it's a lot better than $5500. Interesting, though, that they were able to knock that much off in the first place...

Fluid and filter, done correctly, is the full service. I don't think it should cost you more than $5-600 at the most, from an independent, and it may save you the valve body job. Having the dealer do it might be a waste, since they probably want to sell you the valve body job...

BobSandra

My normally dormant brain cells are saying something may have been overlooked, has a transmission service/oil & filter change ever been done?

BenzNinja

iTrader: (4)

It's rarely the valve body
often the plate
you can get a new one but just getting a used one from ebay virginized will do the job
plate would cost you $350
programming we do





10yo child could replace the plate

Eonetiller

I just had to replace the battery under the drivers seat and the gear shift module because my GLS would get stuck in park. 2018 GLS550 with 48,500 miles.