Vario 814 gearbox 5 or 6 speed ?

[814da]

Hi all I have a dilemma that I am looking to solve I have a 2003 814 vario with a 5 speed zf s5-42 gearbox Center top shifter and would like to fit a 6 speed box also with the Center top shifter !

Question what 6 speed gearbox was fitted to the vario ? Is it the zf s6 -850 ? As this appears to have the shifter on the side and requires a oil cooler?
I have asked mb uk with no luck as they wanted a chassis number off a 814 with a six speed box to work from

Any ideas are welcome thanks mark

 

[Sitec]

Hi Mark. What's the reason for the change? More speed or just better ratios? I believe the ZF 5-42 is already an 'overdrive' box, as it's the same gearbox found in the old Leyland Daf Roadrunner truck... and it's sat behind a 150hp 5.9 Cummins 6 cylinder, so is a strong box. I fitted the Cummins/ZF combination into my 101 Land Rover and never had an issue with the box...

 

[814da]

Hi thanks for the reply I want to improve my road speed ratios as I about to switch the transmission on my truck from 2 to 4 wheel drive I have a donor 814 da 4x4 but having done the maths on the ratios will lose 20% of my top road speed requireing me to do over 2000 rpm to maintain a 56mph cruising speed, if I switch the gear box to a six speed this will bring my top road speed back to 56mph at at 1700 rpm,

The question is which six speed gearbox did Mb fit to the vario ?

 

[Neil]

The original owners mb owners handbook will show all the gearbox options that mb fitted in it

Neil

 

[charlieaarons]

There is virtually no difference between the top gear ratio on ZF S5-42 and current Ecolite 6 spds. Save your money and spend it on changing the diff ratio to your liking.
The S5-42 with deeper 1st had 5th at 0.76. The S6-650 used in some American pickups for a while had 6th at 0.72, only 5.25% faster, not 20%

 

[charlieaarons]

Those transmissions won’t bolt to your OM904. They had proprietary bolt patterns, yours is SAE#3 I believe. Or might be #2 like the 906.

 

[Sitec]

And if you get really stuck, I designed a conversion plate to make a Land Rover LT230 full time 4x4 transfer case fit a ZF 5-42. This gives you full time 4x4, High, Low and a choice of ratios. There's a group on Facebook called Cummins Land Rover Group (CLRG). One of the fella's on there (Reece Myers) has marketed my kit and the billet gear to convert the ZF output splines to the LT 230 transfer case.

 

[814da]

There is virtually no difference between the top gear ratio on ZF S5-42 and current Ecolite 6 spds. Save your money and spend it on changing the diff ratio to your liking.
The S5-42 with deeper 1st had 5th at 0.76. The S6-650 used in some American pickups for a while had 6th at 0.72, only 5.25% faster, not 20%

Thanks that’s valuable information and as you said the 6 speed upgrade would offer a marginal increase the diff upgrades are interesting but I have no information on what options would be available ?

I have conducted some research in an attempt to glean something on front diff options but have had no luck from mb uk do you know of anyone who would could offer options on diff up grades I guessed the guys at Atkinson vos would be a start ?

 

[Neil]

I had my diff ratios upgraded. I initially rang Atkinson and Voss, but they couldntunderstand anything i was asking for. In fact they eventually quoted me on fitting lower ratios than i already had. I was a but shocked that they got it so wrong so opted to go to germany for the upgrade. Expensive but worth it.

 

[814da]

I had my diff ratios upgraded. I initially rang Atkinson and Voss, but they couldntunderstand anything i was asking for. In fact they eventually quoted me on fitting lower ratios than i already had. I was a but shocked that they got it so wrong so opted to go to germany for the upgrade. Expensive but worth it.

That’s interesting who did you use in Germany?

 

[part time nomad]

I was thinking about looking for a 6 speed box for my Vario, Even the 5.25% top gear would be worth having! and if the 1st is lower that could be an advantage too. Both of those coupled with closer ratios would be good.

I can`t help but think that Mr MB spent a lot of time & effort researching the ratio`s on the 4x4 before coming to their conclusion!

I have played about a fair bit with Land Rover gear ratio`s, and found that the manufacturer normally gets it about right, you may have a taller top gear, but find you are always dropping out of it on the slightest incline.

I have not looked in to the ratio on the transfer box, but if it is 1 - 1 in high, then why not fit/keep the standard 4 x 2 difs?

All this said, if I come across a good six speed box I would be very tempted. I think I would get away with the 5.25% the 4 x 4 setup does consume power and fuel.