300 te rpms at 80 mph and above
 

:rolleyes:one more question about the wagon I found today...What rpms should it be turing at 80-85 mph??? I was pushing 4000rpm at 85. Thought it seemed high? Higher than my 300d? hmmmm

seems about right.

Normal. M103 is a high rev motor. You don't really start to get any power out of a M103 until you hit 3K rpm, which is why they're geared so high. If you drive it around town in 3rd gear, you will discover that the car isn't anywhere near as sluggish as you'd thought previously. It can actually be pretty peppy if you are willing to drive it in a way that keeps the motor in the torque range. I usually don't pop it into 4th until I hit 45 with no traffic or lights ahead. On my 300SE, the RPM to MPH ratio is pretty damn close to 50:1 in 4th gear. So, at 60mph you get 3K RPM, 80 you get 4K, and at the red line of 6250 RPM you top out at 125MPH.

A diesel is a lower RPM higher torque motor, so you can't really compare to gas as far as RPMs go.

I keep mine in 3rd most of the time in the city too, unless I have a real long stretch where I am just cruising, then I let it run in 4th at low rpms.

Sounds right to me. My 88' 300SEL runs around 2900-3000 at 60 mph if I recall.

My old 84' 190D ran about 3000 at 55 mph. :)

Swap a 722.5 5speed auto in it and will help you a bit...cheer

Should the original 4 speed auto fail on my 300E at some point in its life.....is the 722.5 5-speed a direct swap in? If I was able to find a used one? That would be pretty cool....

^ Until the overdrive fails on you and you're back to 4 speed ;) I hear its really luck of the draw with that transmission.

Unless you want an extra computer or 2 in that 300, I'd avoid and stick with the 4 speed. They're more robust and can take a beating. Just change the diff and related speedo and you'll drop a few RPMS that way.