6 speed box

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g wagon g
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Joined: 21.04.2014
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Hi I have decided to post it for all and many of my friends on here Spent all xmas holidays from boxing day to yesterday fitting a 6 speed gearbox to my g Big essay ahead please move on if bored Spent all day in cave but rain on roof told me it was not so bad Got 6 speed box with many miles just to try out Top guy delivered it from miles away on route for xmas vacation It will go on, please excuse any spelling miss takes as I'm not checking all this Found a cheap single mass flywheel kit If my miller had been working ok it would of saved 4 32 mile trips to work and back Save the environment I should of left it as it was as the machine was fine before Modified flywheel and thought the clutch might slip under load but continued Made linkages for gearbox but with a thin grinding disc. It was as good as could be To be fair it was perfect and looked like I had machined the item needed Don't joke when you can adapt parts with a skilled gringing hand to very accurate tolerances its skill or luck. It looked machined but I scrapped that one anyway boo hoo It was bang on well the 3rd one Flywheel was a pain Bolts wer hard to obtain in the egth I needed so off to work another time The bearing etc etc etc Took it on and off 4 times as I was not happy with it 100% Bolted gearbox up and modified for a quick swap if needed in future Oh I forgot The time also involved a full front axle rebuid with new diff and wheel bearings cv joints etc Spent a day cleaning and inspecting and measuring parts not a bind just a day or more wasted The ball ache was doing away with the assisted Bowden cable for Mercedes 6 speed gearboxes It woud be easy but a g wagon tunnel where gearlever mounts is way higher than standard box fitting The gearbox rubber mount from a car seems better than a g wagon one so I chose to adapt crossmember for box to suit Spigot shaft bearing for gearbox input needs a mod too All merc parts The worst bit was designing a linkage with no cable assist Its done and I tried it today, well last night to be honest Went a 20 mie run to tescos without my phone. My wife woud of moaned if she had to drive out that far for me lol Confidence is good and bad I broke down !!!!!!!! No not realy ony kidding. It worked well Gears are suited to g wagon with om 606 fitted Revs are a little higher but only a bit It is in the happy power band so much more A 603 would cry out for a 6 speed The box seems more than well used but I will find a low miles one and treat with care. For the money this is the guinee pig and I wont worry if it keels over Slick shift smooth change and I doubt I will go back to 5 speed Might be a bit higher revs in top gear but what a smooth box Cheap too I have not kept it all Mercedes as I did not want cable assist so I made an overkill shift linkage that works well If you wanted to do your own the standard linkage will be fine I just wanted a solid mechanism that would be ok in deep water etc To be honest its a bit harsher in 1st and 2nd but I have got rid of the dual mass flywheel I don't thik I would go to 5 speed again as many cheap 6 speeds available if you can change it yourself If not get a low miles 6 speed and see how it goes I will keep you posted on how my old poorly box copes with the torque Mine was a 130 c180 box in a sad state and I wil give it a hard time If the box does well and lives I will source a good box and I would never go back to 5 speed Gears are suited to a g wagon its just I hope it will cope with the torque Keep you posted Later rather than sooner lol
neilmarton
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Joined: 29.03.2015
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Re: 6 speed box

one GIANT leap for "G"kind !!!

The most technical thing I can remember was changing the sprockets on our mopeds back in the day !

What are the benefits of installing a six speed box ? 

Quicker pull away ? Or higher top end ? Or just a lower gear for crawling and a higher cruising with lower revs so improved fuel efficiency ?

keep on trucking yes

JASONGDS
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Re: 6 speed box

Looking forward to a test drive, someone with knowledge of these 6 speed boxes could list all the available ratios? Or are there so many? 5 speed ok, but at times a bit remote from the box, but still way better than LR! 

Nick123
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Joined: 12.01.2004
Location: Argyll, Scotland
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Re: 6 speed box

Congratulations and respect are due!

When Gordon resurrected our bodgewin'd 406 last summer he mated a six speed manual 'box to the 606 engine and ... Goodness Gracious Me what an astonishing improvement. We are delighted.

In low box bottom gear our SWB G-Wagen will now crawl along steadily at less than a slow walking pace and in high box top it will bowl merrily along the highway. The shift itself is slick and the drive is transformed. You are quite right Gav - it's the way to go.

As for doing it in your man-cave while the rain rattled down, how much hot tea did you get through?

g wagon g
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Joined: 21.04.2014
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Re: 6 speed box

Lower overall ratio in top but only a bit


Reason for swap is bearings are more expensive for 5 speed to rebuild than a good low miles 6 speed box

I will rebuild the 5 speed one day perhaps or just see if the 6 speed lives

I got the cheapest high miles box so if it worked i could select a low miles one. The box seems ok. It catches second gear with a quick gearchange but otherwise its ok


        Happy days so far at 230 miles old

                                              Keep you posted

g wagon g
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Joined: 21.04.2014
Location: uk
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Re: 6 speed box

                  It was not too bad


The hard bit was doing away with the bowson cable assist so its just one linkage thats all metal


Not many cups of tea but a few beers to aid the situation lol

                                               G