Automatic Transmission

[bpossel]

Looking at the BBB, there are 2 transmission types documented...
K4A 025 and K4B 050.  Each one with different fluid level max. when changing the fluid.

How do we tell which trans type that we have?

Thanks.
Bob

bpossel
Memphis, TN.
1971 280SL
1997 E320

[Cees Klumper]

There's a plate on the side. Then also I would guess that the data card, OR e.g. Gunther Engelen's book would give the necessary info. As for how much fluid the trans takes, I suppose you could establish that by measuring the amount that comes out when you drain it completely including the filter?

Cees ("Case") Klumper in Amsterdam
'69 white 280 SL automatic

[hands_aus]

Hey Bob,

There was a discussion in April 05 about auto transmissions. I asked JoeA a question about trans types and numbers

here is the info.

Quote

Hey Joe,
The auto-trans in my 250 SL says it is a GA230sl*E.
Is that the same as the K4A025 auto-trans?

Bob Smith (Brisbane, Australia)
RHD,1967 early 250 SL, auto


REPLY

17 Apr 2005 :  10:17:21  

Hello Bob,

Yes, this is the early version of the K4A025 (notice the 16 bolt oil pan). From what I can decipher, the later version also type K4A025 (16 bolt also) is physically the same but has a slightly different valve body in the transmission. This later version of the K4A025 is identified by "GA 280 SE" label. Both these units are basically the same and are interchangeable.

The early K4A025 "GA 230 SL-E" was used in models 230SL, 250S (up to chassis #3651), 250SE, 250SL, 250S/8.

The latter version K4A025 "GA 280 SE" was used in models 280S/8 (early models only), 280SE/8 early models only), 280SL/8 (all), 300SEL/8 (early six cylinders only with).

A new K4C025 (4 bolt pan) replaced the K4A025 transmission in all the later models except for the W113 that kept the (16 bolt) K4A025 until the end of production.

Joe Alexander
Blacklick, Ohio

end quote

I hope this is of help to you

Bob Smith (Brisbane,Australia)
RHD,1967 early 250 SL, auto

[bpossel]

Hi Bob,

Thanks for the info from the earlier post...

The BBB states that the K4A 025 refill amount at oil change is 3.75 vs the K4B 050 requires 7.75 at oil change.

Bob

bpossel
Memphis, TN.
1971 280SL
1997 E320

[ja17]

Hello Bob,
The transmission capacities should be close to each other. The figures given vary greatly probably because one figure may include the torque converter and the other may not? You should always drain the torque converter during the service.

Start off by adding about five quarts, then start the engine and work the gear selector through the gears. with the engine running check the fluid level. Add a quart at a time and re-check until the fluid appears on the dipstick with the car running. Be careful not to overfill, the marks on the dipstick are about one pint apart.  Leave the fluid level between the marks until after a test drive then recheck and top it off.

If you accidentally overfill, you can bleed off a little fluid by loosening the rubber cooling line hoses from the transmission at the radiator. These rubber lines shoud be checked for condition also. If one bursts you'll be stranded.

Joe Alexander
Blacklick, Ohio