Can't Undersand W114/W123 Auto Gearbox Dipstick

[01alam]

Hello All,

I have just bought a 280CE W114 Auto. Sometimes the gearbox doesn't engage a gear after being slow or at traffic lights, unless I shift to N then back to D.

I checked the oil level of the gearbox, the oil seems fine, but I don't understand the dipstick. There are two "humps" on it. The oil is below the lower "hump", just wondering which level is which?

I have also bought Castrol TQ-D Dexron, I think it will be OK, any comments?

Thanks,
Angus

 

[Dieselman]

It sounds like the ATF level is too low.
The lower hump is for cold ATF, teh upper one for hot ATF.

Check it when hot with the engine running and after running through all the selections and back to Park.

 

[01alam]

Thanks Dieselman, it is way too low, I drove it for 6 miles and leave it standing for 5 mins, and the level was below the bottom hump.

Looks like a cheap fix. That's good!!

Thanks

 

[lynall]

I think its needs to be ticking over when you check the level well it is on mine



Lynall

 

[01alam]

Thanks all,

Just wondering should I add ATF when its hot, or when its cold? Should I add to the top hump?

Thanks,
Angus

 

[nickcc101]

Makes no difference when you add the new oil, just make sure that the oil you are using is the correct oil. Check with MB that Castrol ATF is the correct oil. If you use the wrong oil you will be in for a very expensive repair.

 

[SilverSaloon]

From what i remember reading when i replaced mine is that any Dextron II fluid is suitable for this age of Merc.

I opted for the more expensive MB ATF fluid from the dealer though, just to be on the safe side. It was over twice as much but worth it IMO if the car is a keeper.

Not sure if its wise to top up the fluid.... do you know what type is already in there?

may be best to flush it, and replace all with new stuff. Also change the filter. This will also give you the chance to check the state of the gearbox fluid pan - if its been running so low on ATF then i'd be interested in what may be in the pan, and clean it out etc.

Depends if you plan to keep the car for a good while...

 

[01alam]

Thanks nickcc101 and Silver Saloon.

I might top it up for now and get it changed ASAP. My main concern is that the gearbox is functioning properly, that is my hope!

Angus

 

[grober]

I have to possibly disagree with the definition of the MIN and MAX marks. Automatic gearbox markings are difficult to check/ interpret. Most older gearbox dip sticks are only calibrated for the situation where the engine/gearbox is hot i.e. 80C+ and idling in the P (park) position. The MIN and MAX markings are minimum and maximum levels for the HOT fluid only. They are not the hot and cold levels. When cold i.e. 20/30C the level will be 10/12mm below the Min (hot) mark. Later dipsticks are clearer with min/max markings for 30C AND min/max markings for 80C. On the old 4 speed hydraulic boxes the difference between min and max is a mere 1/3 litre so doesn't take much to overfill. Before adding any fluid I would warm the box up by driving 10 miles and check the level again- if its between the 2 marks(MIN/MAX) at 80C then the fluid level may be correct.
Don't take this as gospel because what I have said applies to 4 speed boxes around 1989-95 .Don't know for certain about your box but your owners handbook may clarify matters.

 

[01alam]

Thanks Grober,

It sounds like I have overfilled the Gearbox oil, I have totally misread the lines, I am way above when hot. Right, need to be off to garage ASAP.

Thanks,
Angus