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Discussion Starter #1
I've read many of the transmission threads and none I can recall quite describe what I'm experiencing.

I got the car with 89,000 miles changed the fluid before 100. Changed the plug thing on the tranny, no oil getting to the control module. The way it shifts has not changed since I got it, i.e., changing the fluid or filter didn't make any difference.

What is happening is when I coast down from a higher speed to a lower speed the transmission often doesn't downshift until I press the gas to accelerate then it shifts down and causes a jerk.

This can happen at different speeds in different gears.

Upshifts are fine, no slipping or flares or anything else that seems weird.

I've done the transmission reset process numerous times and have noticed no change before or after.

Is this normal? If not, what are the likely culprits?
 

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1998 E320 base sedan @ 160kmiles
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5,850 Posts
Hello :).

I guess you have no CEL and codes associated.

Have you checked the ATF level properly (fully warmed up transmission in Park engine running, with the correct dipstick tool). ?

Have you tried running with the gear in 4, and then 3 , rather than Drive, and see if the harsh downshift occurs with these gear selections ?

Have you checked your transmission mount ?
 

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Discussion Starter #3
Hey thanks for the reply!

Correct, no warnings on the instrument cluster or my autozone scan tool.

1. Yes. Appears OK. I'll double check.
2. No I have not. Will do tomorrow.
3. I looked at it. Doesn't look destroyed but doesn't mean it's not tired, not really an expert at that one. I'll explore this more.
 

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Discussion Starter #4
Well, I drove some and tried coasting down and accelerating from different gears and it appears that it's worse when it's in D, or OD or 5 or whatever it is.

Seems like it wants to hold onto this gear longer than the others.
 

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1998 E320 base sedan @ 160kmiles
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Does page 13/7 describe your issue ? if not, which one in the complaints section ?
 

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Discussion Starter #6
Thank you for that trouble shooting guide.

Harsh downshift definitely describes it. Looks like I need to gather more data to see if it fits into one of those categories.

It seems to me its more of a 5-4 downshift issue but it has happened in other gears too.
 

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1998 E320 base sedan @ 160kmiles
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Looks like I need to gather more data to see if it fits into one of those categories.
Good idea.

I would drive it in 3rd gear and see if it has the same problem.

If it is the separator plate, it is the plate between upper and lower valve bodies, and costs about $60. If you can get a used valve body from a Junk Yard, at a reasonable price, it would be a more practical solution IMO.
 

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Does page 13/7 describe your issue ? if not, which one in the complaints section ?
I have same problem. harsh coasting downshift however I am not sure if it is 4-3, 3,2, 2,1 as manual attached has different remedies.

I thought it was ignition related! I was also prepping for a fluid drain/fill for the tranny hoping it would help. However, "harsh coasting downshift" is exact description.

Is this a DIY repair? the seperator plate? "ETC" repair kit mentioned in the pdf? are these shade tree mechanic friendly or is that a big fat no?
 

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1998 E320 base sedan @ 160kmiles
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One can buy the separator plate and repair it, if one follows the instructions in the guidelines, however it may be more practical to replace the valve body with a known good one.

This is, if you are certain that this is the problem. It may not be related to the transmission itself. It could be related to a bad MAF, transmission mount, etc. You need to observe other signs (vibrations, roughness) at idle (in gear, or P/N), while accelerating etc.
 

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Discussion Starter #10
I have been driving it in W mode. I haven't really ever done this but I have found a couple things with this:

I have only felt one harsh downshift in the past week running this way that was from 3-2 and it wasn't that harsh.
The throttle response is way better. Throttle tip in had been pretty abrupt from time to time in S mode.

As far as driving it in 3 I have done it some but didn't notice a lot of difference. It really does seem that the harsher shifts are from 5-4. It just hangs out in 5 way too long.

I'll hopefully get to the mount this weekend and check it out.

I'll report back later.
 

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1998 E320s sedan and wagon
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mrboca, could it be TC lockup not releasing? Is downshift while coasting a mechanical response or based on electric speed sensor?

Sixto
98 E320 wagon 195K miles
 

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1998 E320 base sedan @ 160kmiles
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mrboca, could it be TC lockup not releasing? Is downshift while coasting a mechanical response or based on electric speed sensor?

Sixto
98 E320 wagon 195K miles
Possibly. I had a problem like this with the Honda. I used one of those shudder-fixx thingies, and it worked very well.
Downshifting is based on many things, but mainly the speed. Then, climbing up / down, atf temperature, s/w mode, loading weight, etc. etc. But mainly governed by the speed.
 
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