gearbox conversion

[Flyair]

I just found an interesting item on e-bay: a gearbox conversion from either manual or automatic to a 6 speed gearbox. it could nicely accompany engine conversion for those who like to put a new soul in the classic body.
http://www.ebay.com/itm/Mercedes-SL-6-SPEED-GEARBOX-230-250-280-SL-W113-4-Gear-Sifter-Automatic-/251201985183?pt=Motors_Car_Truck_Parts_Accessories&hash=item3a7cce1a9f&vxp=mtr

[Jack Jones]

There was a seller in the US trying to move these in 2011. I contacted him but after one response that he was going to get me some additional information, I never heard from him again. The seller in Poland refers to these as rebuilt but my understanding is that this is a new transmission. Still interested but would prefer a seller on this side of the pond.

[jmbour]

Interesting, but not cheap !
A new ZF 5 speed would almost the same price, would be more original and would fit.
More information on the gearbow (new or rebuild, what origin ?) and the modifications needed would be welcome.
But : 60 MPH (or 100 KM/H) @ 2000 t/M in a Pagoda, what a dream !

JMB

[Garry]

At 7800 Euro a new ZF gearbox is about twice the cost of this one.  However it does not explain if new tail shaft is also needed that would add to the cost.

When I fitted my 280SL with a Getrag box, I had already fitted a 3.46 rear end and the revs were around 2200 at 100kph (62mph)

It was nice and quiet but had very little torque given that the power in the Pagoda does not come into its own until at least 25-2700rpm.  To be honest, it was almost too low but a real highway cruiser with an overdrive.

[GGR]

At 7800 Euro a new ZF gearbox is about twice the cost of this one.  However it does not explain if new tail shaft is also needed that would add to the cost.

When I fitted my 280SL with a Getrag box, I had already fitted a 3.46 rear end and the revs were around 2200 at 100kph (62mph)

It was nice and quiet but had very little torque given that the power in the Pagoda does not come into its own until at least 25-2700rpm.  To be honest, it was almost too low but a real highway cruiser with an overdrive.

That's the thing.  Best staying in the torque range otherwise it's not really enjoyable.

[Jack Jones]

My recollection is that this is a new Getrag box converted to fit the 113 chassis. I discussed this with a seller from the US in January 2012 and shortly after he dropped off the radar. Remember that this is a 6 speed box and 5th gear is very similar to the ratio on the ZF transmission. You can use sixth gear only when conditions are optimum, i.e. when traveling through the mid west where it is so flat at night you can see your own tail lamps.

[jmbour]

Isn't a 3,46 rear end the best and simplest solution ?

[Garry]

If I had my time again the best solution is to do either the gear box change leaving the 4.08 rear in place or doing the 3.46 conversion but not both.  Many here have done a 3.27? conversion but I assume that they are doing that conversion with the Auto gearbox. can someone else confirm that?

[BaronYoungman]

I have done that conversion with a auto and it is GREAT on the highway.. slower off the line but never my concern with this car
Bob

If I had my time again the best solution is to do either the gear box change leaving the 4.08 rear in place or doing the 3.46 conversion but not both.  Many here have done a 3.27? conversion but I assume that they are doing that conversion with the Auto gearbox. can someone else confirm that?

[pagoden]

I had a 4.08 in my 280SL.  I feel that the experienced owners and restorers who counseled me against buying a Pagoda with that rear end ratio were right to do so, but the rest of the car was pretty much what I wanted.  So what to go to for the back axle ratio?  Using the 4.08 ratio as a starting point for the math, I found that the 3.27 gave a ~20% reduction in revs, the 3.69 was very close to 10% lower than the 4.08 and the 3.46 fell right in the Goldilocks middle with an approximate 15% reduction in revs across the board.  Mine is a standard shift car and I too feel that the 3.46 is ideal for it.  I could have fun with the 3.69 but they seem to've been vacuumed up by previous generations of Pagoda owners, and they're still a bit short-legged for highway cruising.  I imagine that the 3.27 is especially nice in an automatic Pagoda with modification to give first-gear starts.  I also speculate that it sounds and feels particularly right to those whose youthful automotive experiences were with/in V8s.