Need to know Engine RPM for 722.5 Trans. at Hig way speed please?
 

Hi Guys, I want to swap in a 722.5 5 speed trans for my 91 300se. I need an extra overdrive gear to boot up the gas mileages and lower the RPM. Please can any one of you tell me what is the RPM you guys at about 75mph for a 722.5 trans with overdrive on. Right now I have a 722.351 4 speed in it at 75mph it read about 3650RPM or more, incredible high!
Hope you guys share some data for me to compare the beneficial between two trans. Thanks
(BTW, FYI, my trans NOT SLIP, run good just paid $1500 for rebuilt.)

Any one? please.
By the way, FYI who ever own a 300E from 90-96 should have this 722.5 trans and for E300 from 94 to 96...thanks

In part, the final drive ratio of the rear axle really effects your revving at higher speeds.

The E-class / 124 has a 4-speed automatic through EOP / MY '95.
You might consider the taller final-drive of a V-8 or diesel W126.

The wagon's have a suitable final drive I think for reasonable acceleration and somewhat decent highway revving. I thought the 5 speed auto was introduced in the W124 on all models in the 94-95 MY's?

No, still the 4speed.

I think of this each time I drive my SDL into town, ya know that looking for 5th gear. It's also well above 3k at a stiff hiway cruise.

I would love to find out what the verdict is. I dont want a higher rear end gear r/t lack of torque.

I drive a 1990 300SEL with the same transmission. Your RPM at 75MPH is correct for that transmission and that rear end. It is the same as mine. The SE and the SEL with the 103 engine are geared for higher RPM. I know it seems like you should upshift to a higher gear, I felt the same way when I got my first 300SEL, but it's just the way it is.

FYI guys
 

I found this place have some 722.5 trans and data information. But the price is a little high. any more data please share..thanks