300ce with no overdrive - PeachParts Mercedes-Benz Forum

savagehula · #1 12-07-2004, 12:25 AM

i am haiving problems with my 89 300ce's tranny. just a couple of days ago it wouldn't shift into overdrive. it stays on third gear on the freeway, so it's stuck at high rpms. first thing i checked was the tranny fluid which was low but even after i added fluid it's still doing the same thing. hope you guys can help me out!! thanks!!

Chamorro · #2 12-07-2004, 01:31 AM

(I could be wrong about the following; if so, other members will correct me

)

1 - your car doesn't have overdrive. It's a 4-speed w/ 1:1 top gear ratio.
2 - your car likely starts in 2nd gear; that's why you think it's only in 3rd gear. At a complete stop, you can either mash the accelerator or shift into 2 & back to D to start in 1st gear.
3 - w/ a 1:1 ratio, and a (relatively) aggresive rear end, you're going to see fairly high RPM's @ freeway speeds.

jeff-abalone · #3 12-07-2004, 01:31 AM

Did u check the vaccum modulator valve???

rich_ie · #4 12-07-2004, 01:51 AM

Hi Savagehula
When I got my 89 300e from the org owner they sold it cheap because the trans was acting up so the took the cost of the trans rebuild off the price.

Took her home drop the pan the fillter was colged

installed new fillter make sure its on right new pan gasket and it runs like new.

You might want to try it, its not that hard just make sure you have a big pan to catch the fluid and I leave 3 or 4 bolts (loose) in the front or back and open one side of the pan so the fluid run to the drain pan if you pull it down all at once the fluid runs everywhere.
Good luck hope this helps,
Rich_ie

kramlavud · #5 12-07-2004, 07:58 AM

Chamorro is correct. You have 4 forward gears with 1:1 on 4th, no overdrive. The 124 cars started in 2nd gear until about 93 or 94 when the trans was modified to start in 1st. Additiojally the coupes have a lower rear axle ratio which results in the engine turns slightly faster at any given road speed.

Mark

nglitz · #6 12-07-2004, 10:22 AM

In a typical sedan 300E, the RPM indication in top gear (4th) is about half of the MPH indication, i.e. 3000 rpm at 60 mph. I'm guessing your coupe has a higher ratio rear axle so expect higher rpm than that. Or, you could be truly stuck in third and screaming along at 5000 rpm at 60

savagehula · #7 12-07-2004, 12:57 PM

thanks to every one who replied to my tranny problem. i'm going to try the filter change and flush and see if that works.

savagehula · #8 12-07-2004, 01:00 PM

Quote:

Originally Posted by jeff-abalone

Did u check the vaccum modulator valve???

hey there jeff!! thanks for the reply. i use to have a cd of the repair manual but lost it. was wondering if you could email me the location of the modulator valve and info on how to check if it's functioning right. Thanks!!

jeff-abalone · #9 12-07-2004, 04:00 PM

Quote:

Originally Posted by savagehula

hey there jeff!! thanks for the reply. i use to have a cd of the repair manual but lost it. was wondering if you could email me the location of the modulator valve and info on how to check if it's functioning right. Thanks!!

Sorry! i don't have the repair CD as well. Hope that someone can send some more informations to you. No idea where it is located. In my 190E, it is located top of the tranny.

GregS · #10 12-07-2004, 10:09 PM

I wish I could be of more specific help, but I used to own a 1990 300CE that had the same problem. It wouldn't go into 4th gear (come on people, give the guy some credit and assume he knows when his car isn't going into 4th gear

), and it turned out to be some sensor type thing installed on the transmission that the dealer was able to replace and resolve the problem. For some reason I want to say it was a component other than a vacuum soleniod. I sold the car and gave the records to the new owner, so I can't give you more info than that, but my point is, don't let some shop tell you that a new tranny is in store. Take it to a good shop that can diagnose the problem and fix it properly.

Greg