5 speed questions (240D)
 

I have read here and there about some 240's being equipped with a 5 speed transmission. Was it a overdrive transmission, or just a way to have smaller steps between gears? Was it an option, or something that came through on the gray market cars only? Also did the rear end ratio change as a result of having 5 forward gears?

It's basicly the same 4-speed tranny with an overdrive unit bolted between the main body and the tailhousing. It was never an option in the USA, only grey market cars wil have them. From what I've seen, they keep the 3.69 rear end.

They are rare as rare can get over here. If you find one, latch onto it. 5-speed trannies can still be bought and imported over from europe for around $600-700 Euros.

European model 240D, 240TD, and (maybe) non-turo 300D's are the ones to look for.

The elusive five speeds.
 

My understanding is the same as forced induction's basically. I did drop a couple of emails to larger auto wreckers in england seeking a price on one of these boxes but got no reponse from them. Does anyone know of someone vending them? Although it would be better to get one in the states if possible as the driveshaft should be aquired at the same time as it is shorter. My understanding is the overdrive ratio is not particularily large but everything helps with 240ds and I might be wrong about the final overdrive ratio.

280SLs also had them with the M110 motor. BUT again, good luck finding a scrap one. I will probably be selling a four speed setup from a Euro 280E later this year.

I guess I should not hold my breath until finding one... Thanks for the informantion.
J

Four speed should help economy a decent amount over the nonlockup auto. 3-500rpm less at cruise speeds.

5 Speed Difference
 

My 5 sp seems to worth about 10 MPH over (my father's '74 240 4sp) 4th, so you'll be able to cruise at the same speed with that many fewer revs. As I don't have a tach, I haven't a clue what the actual spread is. It's a great car for the flats of Florida, but doesn't have a lot of grunt in 5th and slows a bit on overpasses, even ... Delivers between 31 & 34 average MPG, tho, and will cruise around 80 without apparent strain -- 77-79 is my usual.

Ed

R Leo has a 5-speed 240D. Give him a few thousand $ and he might part with it. :D

Talked to him a the meet in Centerville ,hes got big plans for it i believe.

the od ratio is a little less than 20%. it would transform a 240 on the highway i think.

tom w

really.. wow he's living the life isnt he

It's a 0.83:1 as I recall, so you're right... around 17%. :D

I think the real question is when would you use it? And do we really want low rpm's?

4th at 80mph is fine with me with enough power to switch lanes and pass semi-trucks. 5th is probly a good idea above 80 and would be great for doing 90mph, otherwise strikes me it would be worthless below 75.

At least on a 240D. A turbo OM617 would have plenty of power to cruise at 65mph in 5th all day.

Yeah but what's the point in lugging and bottoming out the power band? I dont get it - hard to believe the sacrifice in performance is worth whatever fuel economy somebody expects to get. And even that might be a myth, am not convinced that bottoming out gears with engine operating at 30% efficiency improves fuel mileage at all.

In the RPM@60mph thread it was demonstrated the w115 220D doesnt even produce 50hp until it hits 3000 rpm. Lugging along at/near 1800rpm (65mph in 5th?) strikes me as painful for both the car and driver.

(edit: I realize I'm not speaking for everybody here. But for me kicking the 240D, maxing out the power band and paddling through the gears to optimize performance is major part of the 240D experience. And should be the same with 617's too, not much fun fouling the chambers at low rpm's and driving under conditions of incomplete combustion. For me these diesels come alive at 3000rpm and anything less is nothing.