hey guys

my friend had bought a 1992 300E a coupel months ago and i was very happy about it all and decided to get one for myself. Well in his and my newly purchased car, when the transmission shifts into i belive 2nd or 3rd gear it gives it a hard kick. I have realized this only when i accelerate a little too hard. wat ar some solutions if there are any.
I bought this car to replace my 5 speed 1990 Toyota Supra. So im still adjusting to being a calm driver.

 

First off is it hard on shifting up or downshifting?

I have a 1990 300E and have the same issues with my car when i floor it and a downshift occurs rather harshly. My mechanic at the benz dealer that i have used for quite sometime said that it is normal and actually better than smooth operation. He explaned that a smooth shift actually slips the clutch more and that it is harder on the transmission...in other words if it smooths out over time noticeably, take it to get checked out. I hope this helps to put you and your friend's mind at ease...ENJOY YOUR NEW BENZO!!!


ZorroAMG

Pearl black 1990 300E
17" AMG Mono for winter, 18" Brabus Mono VI for summer
94-95 Taillights and corner lenses, AMG Duckfin Spoiler
Intrax Lowering Springs, Koni Shocks, Eibach Sway Bar
Remus Exhaust, Brembo Cross-Drilled Rotors

 

To make the car shift sooner you do adjust the control pressure (bowden) cable, you will need to allow several MM clearance at the throttle linkage.

However to change the shift firmness you will need to adjust the vacuum modulator on the transmission.

For a harsh 3-2 or 2-1 downshift, you would benefit from a lengthening of the control pressure cable.

 

If you are NOT accelerating hard then you'll start outa second (you probably already know this). If you aren't pushin the car it should be smooth.

If you ARE accelerating hard then their will be a big kick from first to second gear. To lessen the kick, ifyou want speed and comfort for your passengers, get well aquainted with the shifter in the console. Put the selector in 2 from a stop and floor it. Once you approach or just enter into redline shift it, or let it redline completely for a somewhat rough kick. Past second their should be no rough shifts. If you are having problems from 2-3 then do what the other guys said . But if you are shifting bad from 1-2, they're all like that and you just gotta get used to pushin your Benz. She's designed to handle it !

These car's transmissions are pretty complicated for their original design (made in the eighties). It took me a few months to REALLY get aquainted with my car's engine and tranny for best performance .

 

Actually, 1992 is the first year of first gear start, so this car is always starting out in first gear regardless of how far he presses down on the accelerator.

In 1991 and older 300E's, they always start in second gear unless you:

1. Mash the accel. pedal to the floor to engage the kick down switch

or

2. Move the gear selector all the way down to 2. You don't need to leave it in 2. After selecting 2, you have engaged first gear start whether you leave it in 2 or push it up to D.

 

Ahh! Well, us benzies from the eighties are often left in the dark !! Anyway, I didn't know that, I'd assumed only 500E's were first gear starts, but never mind...

 

Well actually, 500E / E500's don't have first gear start. I have no idea why they didn't.

The two most common upgrades to these cars is a modification to the valve body to engage first gear start at all times, and a defeat switch for ASR.

Another strange thing 500E's don't have is limited slip differential (posi-traction to you Detriot muscle car fanatics).

All of the W126 chassis 560 SEL's have limited slip differential.

I guess the engineers relied on ASR to stop the slipping of the rear wheels...

 

The guy I talked to on a forum had a first gear start. Must have been an add in. I'm striking out at a very post, he he!

Anyway, that does bring up another topic. Is there somin you can do to the pre-1992's or whatever to get it first gear start? I actually like second gear start, but it would be sweet if you could set up some sort of system in the car to control whether you do or not. The delay can help ya lose seconds in a race ...

 

Yes. Your transmission can be modified to do a first gear start.

Bergwerks sells a kit that you can order and have installed. They have two different kits depending on the year of your car. One is a valve body modification. The other is an electronic switch.

http://www.bergwerks.com/e_w124.jsp

 

ya the problem is when i take off and only on the upshifting. the downshifting seems a little rough as if im driving a manual and both the clutch and accerator have been released. well is there any sort of transmission fluid i can put in to help ease the kick liek some of those racing auto transmission fluid.

Driving slower is not an option at this point. I use to drive a manual toyota supra and it is instinctive for me to push my babe pretty hard.

Thanks

 

Like I posted earlier, you can take your car to a mechanic and have him adjust the vacum modulator on the transmission to adjust the shift firmness.

 

is it possible for me to adjust it myself?

Where is the vacuum modulator located?

 

The modulator valve is on the drivers side of the transmission, identified by a green or red color. It should have a rubber cap over the adjustment. It is right above the pan.

Turning the screw counter-clockwise softens the shift. Clockwise makes firmer shifts. This takes about thirty seconds once on a lift.

The less vacum the modulator valve has going to it, the firmer the shifts are. Also make sure you don't have a vacum leak in that system. Make sure the vacum line isn't cracked and that the cap on the modulator valve isn't cracked. If after this change you have shifts that flare while others are still firm then you have an internal problem. It is real concievable that you have a valve body problem.


What you don't want to find is that someone adjusted the modulator valve to cover up a slipping/dragging shift problem due to wear in the transmission.

 

Thanks alot, il take a crack at it tomorrow and let ya know how it goes or if i have any problems.

Thanks alot