87 300D rpm/speed Q

[BodhiBenz1987]

I know this one's been done before, but my search yielded sort of vague results, so I figured I'd just ask with a new thread:

What rpm should the tach read on my 87 300D when cruising at 60-65 mph? My dad insists that he remembers it running at around 2100 during high cruising speeds ... this seems a little absurd to me, and mine definately runs in the 2500-2700 range when going between 60-70 mph (depending on grade of course). Are my rpms normal? My dad hasn't driven the Benz for a few years, and he's been driving big rig diesels singe then, so it could just be that he's gotten so used to them that he forgets the MB's ratios.

So, can anyone tell me at what speeds (assuming flat terrain) the tranny ought to shift from gear-to-gear, and what the normal range of rpms are at the range of speeds? I'm just curious so I can compare to what my car does, and I couldn't find it in the manual or Bentley "ECLass Owner's Bible."

In the event that a car had inappropriate rpm at a certain speed, what might that be indicitive of? I don't suspect a problem, but am just curious. As usual.

[Jim H]

For What It's Worth: my 86 300SDL
70mph = 3,000 rpm
65mph = 2,500 rpm
55mph = 2,100 rpm

Depends on what 'highway' speed you have in mind.

2,100 at 65-70 would be low, in my opinon.

[BodhiBenz1987]

Originally Posted by Jim H

For What It's Worth: my 86 300SDL
70mph = 3,000 rpm
65mph = 2,500 rpm
55mph = 2,100 rpm

Depends on what 'highway' speed you have in mind.

2,100 at 65-70 would be low, in my opinon.

Looks like almost exactly what me car does ... only at 70 mph its usually more like 2800 rpm and goes to 3000 around 80 mph

[mbonly]

my 87 300d does 80mph at 3000 rpm's as far as the shift points go I've fiddled so much with the bowden cable that no longer know what it was before I just adjust it every once in a while to get it to hold gers a little longer and then readjust it to get it to shift early depending on how I feel and where I'm going, if I have a trip coming up to a hilly place I adjust it to hold gears longer to baby the tranny. At 65 it does about 2600 rpm's. I started a tread the other day about how nice it will be to have a 5 speed auto from a newer Benz in the 603 powered cars I think it will be more relaxed at 85 to 90 and the 603 can definitely haul after 2700 rpm's so the taller gearing will not be a problem.