75 300d trans ? - PeachParts Mercedes-Benz Forum

subman60 · #1 08-23-2016, 01:23 PM

I located one for a decent price $750. However the owner tells me the rebilt trans will not shift into 4th. I asked him how it shifted into the other 3 gears and he said not a problem. Where could the problem lie?

Frank Reiner · #2 08-23-2016, 02:09 PM

Quote:

Originally Posted by subman60

I located one for a decent price $750. However the owner tells me the rebilt trans will not shift into 4th. I asked him how it shifted into the other 3 gears and he said not a problem. Where could the problem lie?

Since the 722.1xx starts in 2nd, the seller may think it fails to shift into 4th, when it actually is shifting 2-3-4.

subman60 · #3 08-23-2016, 02:21 PM

Let me see if I understand. This cars transmission when in drive skips 1st gear and takes off in 2nd gear. If that is so then does that mean 1st is only engaged when the lever is placed in L? Sorry if this seems like a dumb ? But I'm not familiar with this series MB.

Zulfiqar · #4 08-23-2016, 02:49 PM

Quote:

Originally Posted by subman60

Let me see if I understand. This cars transmission when in drive skips 1st gear and takes off in 2nd gear. If that is so then does that mean 1st is only engaged when the lever is placed in L? Sorry if this seems like a dumb ? But I'm not familiar with this series MB.

yes - you understood correct. Benz which have 2nd gear start will engage first gear when the shifter is put all the way to the lowest position.

OR

put all the way to the lowest position and then put back in D while not moving - that way the trans starts from 1st gear and does 3 shifts do get into 4 gear. In normal driving conditions only 2 shifts occur, 2-3 and 3-4.

subman60 · #5 08-23-2016, 03:00 PM

i think I'll go have a look at it then. I'm guessing what to look for on this model is going to be the same for the W123 series? Mainly rust.

Frank Reiner · #6 08-23-2016, 04:29 PM

Quote:

Originally Posted by Zulfiqar

yes - you understood correct. Benz which have 2nd gear start will engage first gear when the shifter is put all the way to the lowest position.

OR

put all the way to the lowest position and then put back in D while not moving - that way the trans starts from 1st gear and does 3 shifts do get into 4 gear. In normal driving conditions only 2 shifts occur, 2-3 and 3-4.

subman:

There is one more "OR" in addition to the conditions mentioned by Zulfiqar:

The trans will also start in 1st when D is selected and full throttle (kickdown) is applied from a stop. In the event that the kickdown switch is defective, the trans will start in 2nd.

bricktron · #7 08-24-2016, 12:32 AM

how does this trans differ from the ones used on a W123?

Frank Reiner · #8 08-24-2016, 12:09 PM

Quote:

Originally Posted by bricktron

how does this trans differ from the ones used on a W123?

The 722.1xx was used in 123s as well as 114/115s, 116s, with the same characteristics.
The 722.3xx was also used in 123s, appearing in the early 80s (1982?).

Stretch · #9 08-24-2016, 10:27 PM

Ummm

Not all 722.1 or 722.3 transmissions start in second gear. Many of them start in first as you'd expect.

I have not managed to find any definitive Mercedes documentation that specifies exactly which transmissions be it type or serial numbers start in second or in first.

It seems to me that it is possible that "4th gear does not work" is just as likely as "it starts in 2nd"