Auto gearbox's

[The Patrolman]

Rick, I thought that was the case:thumb2
But where does overdrive sit within 1, 2, 3 and 4:nenau
Is it an actual reduction gear like on the old mgb's if you revved them too high and knocked the od off they would over rev.

 

[The Patrolman]

If my maths are correct,......
With a set of 2.8 differentials and 37" tyres there should only be 4.5mph difference between the std 265\70\16 tyres and 4.2diffs. If I get the speed compensator too that should make for a pretty rapid and less uneconomical truck:thumb2

 

[solarman216]

speed 3 is direct drive, (assuming fluid converter clutch locked) so prop is turning at engine speed, 4 is an increase gear or overdrive, so prop is turning faster than the engine, if you were in 4 and turned OD off at max revs I think the control unit would not permit it to drop out till engine revs dropped to a safe level, on the old MG's etc the OD was an add on unit that was simply solenoid operated so yes you could turn it off with nasty results, Rick

 

[The Patrolman]

As my od appears not to be active at the moment I cannot check its operation.
I'm sure that it had an effect in 3 and possibly 2 and 1 also:nenau
Why would you have an od button when you can kick down to 3 by giving it more beans on the loud pedal.
We will get somewhere between us Rick:thumb2
I've tried posting my excel table which may be useful for other tyre sizes n diff combos but its not having it atm:nenau will have a go with a proper PC tomorrow:thumb2

 

[solarman216]

I have to say I am no expert on Auto's and have rarely driven one, I would not have thought the OD would work on all gears on an Auto as this would require a separate epicyclic section on the rear, and I saw nothing of this when I stripped briggies box when it failed, he in fact would be able to answer your query re operation better than I, Rick

 

[The Patrolman]

I've tried finding a manual in the help sections, I had one before but lost it. :doh
I'll keep digging for clues:thumb2
So far it ain't broke so don't need fixin':thumb2

 

[solarman216]

I have a owners manual that covers the Auto box, seems pretty much as I said OD is 4 but there is a Auto/Sport/Snow switch, so between the two you should be able get what you need, PM me your address and I will send it to you, Rick

 

[macabethiel]

As my od appears not to be active at the moment I cannot check its operation.
I'm sure that it had an effect in 3 and possibly 2 and 1 also:nenau
Why would you have an od button when you can kick down to 3 by giving it more beans on the loud pedal.
We will get somewhere between us Rick:thumb2
I've tried posting my excel table which may be useful for other tyre sizes n diff combos but its not having it atm:nenau will have a go with a proper PC tomorrow:thumb2

On my old r3mR the overdrive switch stopped working. I investigated and found the wire had broken. It was a fidly job as it ran partway down the centre of the gearshift lever. Fixed for the cost of a couple of blobs of solder and some wire off an old set of Christmas Tree lights.

 

[The Patrolman]

On my old r3mR the overdrive switch stopped working. I investigated and found the wire had broken. It was a fidly job as it ran partway down the centre of the gearshift lever. Fixed for the cost of a couple of blobs of solder and some wire off an old set of Christmas Tree lights.

Thanks, the issue of it not working is not a problem, yours would be the first line of fault finding.

I am trying to ascertain the way in which the autobox and overdrive affect the gearing of the car now I have 37" tyres on and the best way to get into top gear and reduce engine speed when on long journeys.

If I can get into top gear with od off is this still higher than third and lower than fourth.

The quest for answers continues:thumbs

 

[The Patrolman]

On and I might have got my calcs sheet to upload too

 

[The Patrolman]

Well had a little run this morning and the overdrive button is working and the revs do increase slightly when activated.
Not too sure how this helps me but it does mean I don't have to fix anything :thumb2

 

[solarman216]

Well had a little run this morning and the overdrive button is working and the revs do increase slightly when activated.
Not too sure how this helps me but it does mean I don't have to fix anything :thumb2

surely when you activate OD your revs will drop slightly, Rick

 

[The Patrolman]

yep that's right :thumb2
but in Troll land the OD is always on and you push the button to turn it off:nenau
I did notice it works in 1,2 and 3 as well as top so its possibly an additional gear set not just an additional gear:nenau

Any Ideas if Nissan do a proper explanation of all the gearing options on the auto boxes - probably in an owners handbook that no one now has:naughty

 

[solarman216]

Ah neat, so in effect you have 8 gears, bit like trucks were you can go up or down half a gear at a time, Rick

 

[The Patrolman]

Even neater it works in low box too so I have 16 gears:clap:clap

Trolls rock:thumb2

 

[solarman216]

then that must mean it is a box on the output shaft, mean these trolls, do they do them in SWB? Rick

 

[The Patrolman]

then that must mean it is a box on the output shaft, mean these trolls, do they do them in SWB? Rick

Oh yeah!!!

 

[solarman216]

then I will have to start looking for one to replace my current worn out and tree damaged SWB Mav, Rick

 

[solarman216]

had a quick look around, but nothing for me all far too dear, and not many SWB I need a motor that I can purchase spare parts for cheap when I break em, do not think the Trol comes into that category, maybe I will pack it in and do something else for the adrenalin, maybe hang gliding or something, Rick

 

[The Patrolman]

There is a chap that is buying all of the Trolls and taking them all to Poland.
if you look on ebay there are no Y60 D Trols about these days

I bought my first D for £995 it was exported for £2000:doh