Tranny slips 2nd -3rd
 

My 91 190E 2.3 transmission slips going from 2nd gear to 3rd. This is really noticeable when merging on to the freeway.Fluid level is correct and fluid doesn't smell burnt. I'm at my wits end.

What are the other upshifts like and what are the downshifts like?

If the other shifts are also sloppy then you might be able to alter the modulator pressure to tighten up all the shifts, this will affect both up and down shifts on all gears so unless they are all this way it won't be of much help.

The 2-3 shift is the most used shift generally and therefore the clutches and bands get the most wear.

Matt.

tranny slips
 

Hey, Mattman. Thanks for getting back to me so fast. All the other gears work fine, up or downshifting. I've talked to a few 190 owners and they said most MBZ's with automatic transmissions inheritably have this problem. Please tell me they are wrong!

You don't say how many miles you have however 100k ish would be about right.

My tranny does the same, but is ok once the temp comes up. Is it getting too much vacuum when cold? I too a glance and did not see the modulator cap on the side. Is there a temp switch on the head somewhere used for modulating the transmission? This is on my 190D 2.5.

I've been wrestling with the 2-3 flaring for over a year on my 300E. According to Gilly, there is a little known repair kit for this problem known as a K1 accumulator kit. It costs all of $2.71 from MB. I don't know the part number for your trans, but the one for mine was 126-270-44-77. Esentially, its a spring kit. I haven't put it in yet (waiting for the Rover to get out of the repair shop). For less than three dollars, its worth a try. There is also some literature out there that points to the B2 reaction valve. Do a search on trans flaring and you may come across it.

If you do the k2 kit KEEP THE OLD STUFF!!!!!

Otherwise, when you rebuild, you'll be sorry. :D

Reinstall the original spring kit when overhauling.

Otherwise it works.


Joe

If you have hard downshifts and minor flaring on the other shifts this kit won't fix the problem.

Matt.

I have a hard 2 to 3rd shift and a flare on the 3rd to 4th shift only when the car is cold once she is at operating temp it goes away. 1991 560sel anyone tried the K1 kit for this. thanks
m

flaring 2-3
 

My E320 (95) is doing the same thing. Does it require transmission r&r or can the shift kit be installed in place without removing the transmission?

tranny slips 2nd-3rd
 

The other shift changes are normal. Other 190E owners have told me that MBZ automatic transmissions leave a lot to be desired. Tell me they are wrong!!

tranny slips 2nd-3rd
 

I think that the K-1 accumulator kit sounds like a good start. Has anyone out there installed one? What is a B-2 Reaction Valve? It sure helps to have all this knowledge out there. If this knowledge doesn't work, would Tank send his transmission fairy to California?

I am supposed to receive the spring kit today from MB. It should be installed next week, I'll let you know if the $2.26 kit cured a over a year of aggravation.

The B-2 Reaction Valve is the brake on cultch plate prior to the shift ( I think). I'm no mechanic but I have looked deep into this problem over the year. If $2.26 fixes the problem, I'll be very pleased and very p!$$ed off over all the money I have put into a vacuum module, 4 flush and fills, several vists for cable adjustments, dropping the pan and filter exchange... But its the brightest trans fluid I have ever seen!:D

tranny slips 2nd - 3rd
 

I'll keep my fingers crossed for you, esm6869. Hope it works. Good luck!

Re: tranny slips 2nd-3rd
 

Well, it's hard to say. They are a very very good autobox, in their day these were called by far the best automatics around. BUT, they are not bulletproof, and as the cars get old and more worn, they tend to be one of the first big things to go.

later

synthetic oil
 

Flowdrip,
I am not sure this helps but I had the hard first shift and the nice 2nd-3rd flair when cold especially frustrating when merging. I put in synthetic oil and new filter this weekend and the hard shift is better anf the flair is gone. I think I will adjust the vacuum on the hard shift to see if I can get that smoothed out.
hope this helps you.
m

Tranny slips
 

I'll try that the fluid change this weekend Martin, It's a helluva lot cheaper than rebuilding a tranny!

flare in the gear change
 

I have seen this comment a few times, but am not sure what you are referring to. I am aware of the cold shift delay for the cat. to heat up..blah, blah, blah , but how does the tranny react during a "flare" and how does it feel from the driver's experience when it happens? Is this another version of the delayed shift or is it felt like an abrupt change at the end of a longer than usual stretch of acceleration instead of a smooth and almost unnoticeable change?

hocky
 

my understanding of a flare is the tranny trying to shift for a long period of time past where it normally would. As a driver it feels like it needs to change and engine feels like it does not have much power but it just stays in the gear, as soon as you release the gas pedal slightly it will change into the next gear and loads of power again. I hope that is what others consider a flare sure does make for an interesting thread if we all think it is something different.
m

I consider a flare to be when the transmission attempts to shift and the engine revs out as if the trans is slipping. The trans eventually catches and the gear changes however it takes longer than normal and the engine revs out in between.

Matt.

Mattman, That was a much better description.
martin

Sorry for the delay, but I just had the K1 Spring Kit installed and it solved the trans flare problem that I have been fighting with for over 16 months!!!!!!! It cost all of $2.26 from the Benz Dealer. This car has never shifted and driven as well as it does now.

A special thanks to Joe P. and Gilly for the information that they provided. I was ready to give up on the car and sell it due to the trans flaring, but now I would not consider parting with this car. May she live long and enjoy the roads.

esm6869

this is great! What is the procedure to intall it? Do you have to remove the valve body?

The valve body does not need to come out. You just drop the pan and remove three screws from the end plate of the K1 accumulator. Pull out the piston with the spring assembly, replace the two springs. Check your seal rings while your in there and put it back in. Put the end plate and the pan back on and the install is finished. I went further and made sure the pressure to the vaccum modulator was what the book called for and had the cable adjusted. At near two hundred thousand miles, this car shifts better than any of my vehicles!

esm6869

Thanks! This is good news. The trans on the '91 300E (200k) has been adjusted for first 1-2 shifts to compensate for 2-3 flaring. How is the shift quality now, especially the 1-2 shifts?

You said "Check your seal rings" would you mind explaining this a bit further. What woul I be looking for and what do I do if there is a problem?

Anyone have the part number for the K1-spring accumulator kit?

My car is 1995 E320.

Thanks

I don't know what number trans the '95 E320 has, but the spring kit that I used will work on the 722.3, 722.4 and the 722.5. That part number is 126-270-44-77.

Again, a big thanks to Joe P. at Behind the Star and Gilly at Zimbrick European for pointing me to the spring kit!!!

That's great! I think 722.3,4,5 were the only transmission used in 6 cylinder gasoline engines in W124. I just called my dealership and of course they never heard of it. They will order it for me, however.

Now, Are there any instructions that come with this kit or can anyone give me a quick note as to the procedure?

Thank you

Instructions do not come with the kit, only two springs and a couple of plastic pieces. Very little in parts, BIG OUTCOME though.

That's great if that kit will solve your problems, I have just had my trans apart for a similar problem and due to the car having been driven for quite a while with the flaring the bands and clutches were all shot.

Just got the car back with a reconditioned transmission and it's like new again.

Matt.

W123 Flaring 2-3
 

I just took my 83 300d for its first short drive and everytime it would flare (in between shifts the motor seems to free rev for a second or two, until I let off the accelerator and it goes into third) horribly into third. I've been reading this isn't all to uncommon for 123s, but it sure doesn't make me feel very comfortable. I tried adjusting the bowden and it only made my 1-2 noticeable and quicker/harder going into D. Maybe I should try getting a new modulator? It has brand new Castrol Dextron/Mercron III fluid (old fluid was pretty clean) with a new Febi filter in it. Any advice on how to best adjust this out or even knowing someone else's does this too would be great peace of mind, and very appreciated.

Thanks,
Jeff M.

For the last couple hours I've been piddling with the 83 and managed to get the flaring down to only like 500rpms which I can live with, for now. Before it sounded like I was going to hit redline before it'd shift. I found I have a minute vacuum leak on the line going to the modulator, it takes about thirty seconds for it to go from 14" to about 1" of vacuum. I noticed many of the rubber fittings on the end of the lines are getting all checked so I'm going to replace this anyway, but will this minute of a leak really affect my flaring problem anyway?

I also found this while looking around:
So it just has a cover which I pop off and give it a turn?

~jm

There should be a little rubber dust cap. It has been some time since I have done this, but if I recall correctly, you take it off and inside is a T shaped handle that you pull out and twist clockwise to increase pressure.

I would try to avoid any flaring if at all possible. It is my understanding that when the trans flares it rapidly wears your "clutches".

Someone very recently had posted how they changed the rubber connector between the plastic vacuum tube from the engine area going to the vacuum modulator valve. They said it didn't look cracked but was hard. They replaced it anyway and the results were "very impressive". There are MANY threads on this topic ... here is one:

Adjusting the trans mod valve

Haasman

Here is a side view of a trans which might help:

Thanks a lot haasman. Both my 300s really could use some tweaking in the shifting, this flare has to be horrible on the tranny. Picture really helped too, now I know where to look. :)

Jeff M.

Hi,

I have a 90 300CE, the trasnission was rebuilt about a year ago. The transmission started flaring about a month ago on shifts from 3-4, but only when the car is warmed up.

Seemed like most of the people said theres did it when it was cold. Do you think the spring kit will fix my problem as well, or could it be something else? Do you think this kit is a DIY job or should I have it done by a tech?

Thanks for your input, greatly appreciated.

Dean:
The kit that I posted the part number on specifically addresses the slipping or flaring on 2-3 upshift at partial load. I would hate to tell you to try the kit and screw something up. I'm not mechanic, but a flare at 3-4 might be low pressure at the vacuum modulator or a small leak.

I am sorry to post this again,but does anyone have any info on installing this kit? Any help is greatly appreciated for this DIYer.
I got K2 accumulator spring kit.

Thanks
95e320

Did you look at the previous pages to this thread? Does this help?

95e320: I do have an install diagram, but the spring kit that I had put in was the K1, not the K2. The K2 position is on the opposite side of the valve body.

My old 1977 280E, which my brother now drives, has a flaring shift from 2-3. Everything else is normal. It was doing this when I first bought the car about 100,000 KM ago. I was worried about it then and had it looked at several times by several techs, got it tweaked, etc. Nothing helped. So I just changed the fluid every 40,000 KM and she's still purring along, albeit the flaring shift from 2-3. The car's total mileage is around 300,000 KM, original transmission.

A tech once tweaked it so that the 2-3 shift was more smooth, but then the other gear shifts were not. I chose to live with the rougher 2-3. It really drops into 3rd with a solid clunk, but it has never worsened. It seems the rough 2-3 shift is not uncommon.

ESM6869,

Do you think this may be just a simple adjustment, or a vacuum leak? Any chance its a DIY thing? Should I start a seperate post?

This is my second transmission, since I ve had the car and Im verry easy on it. Kills me to think it may be going again.

Any input you have is greatly appreciated. Thanks in advance!

Sorry it was K1 not K2

Does that K1 spring apply to the 1992 300D 2.5 Turbo? I have increasingly worse 2-3 flare as the car warms up. No flare (or much reduced) when flooring it. I really want to get something like this installed before toasting my tranny!

Thanks much for additional info! This sounds like a life saving upgrade!!!!!!

-m

Mercedes300E:
Sorry I haven't responded...been out of town. When I was having trouble with 2-3 flaring and 3-4 flaring, the 3-4 flare went away when I had the vacuum modulator replaced due to a small tear in the bladder. I think proper adjustment and checking for a vacuum leak may help you. If you really want to get good information on your situation, private message "Joe P" at behind the Star in North Carolina or I think Gilly's screen name is "Gillybenztech" at Zimbrick European of Madison, WI. They were very helpful and offered great information to help me.