Notice: We request that you don't just set up a new account at this time if you are a previous user. If you used to be one of our moderators, please feel free to reach out to Chris via the facebook Outerlimits4x4 group and he will get you set back up with access should he need you.
Recovery:If you cannot access your old email address and don't remember your password, please click here to log a change of email address so you can do a password reset.
Yeah its just an automatic clutch manual. They have limitations, including with shift speed.
Merc actually built the best off road transmission ever - it was available in the Unimog - an 8 speed manual with a crawler box and a torque converter- allows left foot braking and stopping and starting in gear, but on the move drives like a manual.
We also have a MAN 4X4 truck at work with this system. It's the business.
Mazda apparently built a gearbox like this (known as a TQ) behind a 13B rotary in a small coaster style bus. Mightymouse and I spent some time around a campfire bench racing that little idea
Steve.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
Gwagensteve wrote:
Merc actually built the best off road transmission ever - it was available in the Unimog - an 8 speed manual with a crawler box and a torque converter- allows left foot braking and stopping and starting in gear, but on the move drives like a manual.
Its not just the transmission
I was wondering if this had been done, now I know. Does the clutch run after the torque convertor? Does that mean it has a clutch, but you couldn't stall it (as much as you 'cant' stall an auto anyway)?
Wheeling on completely wicked angles, without even looking stable.
I was wondering if this had been done, now I know. Does the clutch run after the torque convertor? Does that mean it has a clutch, but you couldn't stall it (as much as you 'cant' stall an auto anyway)?
I know it's been done. But I don't know anyone who's done it.
With a lockup switch for the torque converter, it'd be a great offroad transmission.
Highway-Star wrote: Does the clutch run after the torque convertor? Does that mean it has a clutch, but you couldn't stall it (as much as you 'cant' stall an auto anyway)?
Yes, clutch after converter. I have seen the exploded diagram from the unimog service manual.
Yes, you can stop and start without clutching in any gear. It won't stall. You still have to clutch to engage a gear as the converter still loads the transmission just like in an auto. In the MAN (V8 air cooled diesel, coils all round, planetary hubs, permanent 4WD with centre and rear diff locks) You start in 4th on the road and use the top 4 ratios only. the lower three are for off road. The MAN has no low range.
In the mog, it was available with any of the crawler box sets, so I believe it was possible to order a 3,XXX:1 low 1st with the converter. speeds are measured in metres/hour at peak torque.... I think they do 250m/hr or something stupid setup like this. Patrol42 probably has more info on this stuff though.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
Now Dad wants to know how to fit one of these transmissions to his lux (yeah right).
It really is the best of both worlds isn't it, not only for offroad ability. You wouldn't have use the clutch in traffic, just drive it like an auto; and I imagine you wouldn't have as poor economy as a true automatic; and still the fun of using a clutch and gearstick .
Wheeling on completely wicked angles, without even looking stable.
(I hope y'all don't mind me bringing up an old topic!)
From the first page:
Gwagensteve wrote:
N*A*M wrote: can you push start your auto?
Yes I can. the pump is on the tailshaft end of my auto. It's acutally better to tow start themand neutral drop them into drive, but it does work.
Auto's with plenty of gear reduction also can be bump started.
You can push start an auto?? Could someone please explain in more detail? What gear, or just in "D" in high range (from "N," of course)? What's bump starting?
I've always heard that you can't push start an auto, so this is sounding good!
Having had both in the one car - the Auto wins hands down.... especially with crawler gears.
I was a bit skeptical at first, but watching Steve's GWagen and cj's Vit doing their stuff ( with control ) changed my mind.
Running away down hill just doesn't happen with a properly geared auto, in low low I often have to accelerate on even the steepest downhill sections. With a manual it was two feet on the brakes and hope.
As for being in control - mines fully manually controlled from the dashboard - it doesn't change up or down by itself. I no longer suffer from the "shit I'm in the wrong gear" trauma on hills just click up or down - instant shift, no loss of speed, no breaking traction.
And the ability to not have to do the three pedal shuffle on hills to take off is priceless.
Wouldn't have one in my road car but I'm an absolute convert for a 4x4.
( usual disclaimers )
It seemed like a much better idea when I started it than it does now.
AUTO ...did my comp rig a few years back,I personaly prefer it,& I now seem to have less breakages(or might or changed driving style as well) & as for going quicker down hills,I just keep tellin myself its a comp truck..
DAIHATSU FEROZA UTE,V6,caged,lokd 35's
NOW SOLD
& then
GQ DUAL CAB TUFF UTE,caged,lokd,35's
NOW SOLD
& then
JK WRANGLER 4 DOOR TUFF TOURER,lifted,lokd, 35s
Gwagensteve wrote:autos and diesels make very good friends. Mostly, it is due to to flat torque curve and limited revs that seems to make them work nicely.
Also, with turbo diesels, the stall speed of the converter covers the doughy off boost reponse- Small engined cars like Disco's are better in auto than manual because of this - they won't pull at all when off boost, but the auto ensures they don't fall off boost on gearchanges and always pull away on boost.
Steve.
I can attest to that, once on boost i can suprise a few cars and the disco is quite nippy for 2t of british alloy/ steel. My first 4by was an LJ50 zook and that little sewing machine would crawl everywhere and over anything, next was a 2dr 4spd rangie, 1st low was great offroad i could get out and let it idle down the steepest Toolangi slopes and even in high in stop start traffic it rarely stalled. Next was an auto 4dr rangie with TF727, what a power sapping box that is but brilliantly smooth and effortless in low range, my tdi disco was a different ball game but much easier to control and with converter locked up and a little acceleration it can be controlled on fairly steep slopes although not nearly as steep as the old 2dr rangie could handle. Day to day in traffic and on long tours the auto wins hand down.
Saddle up tonto, its the not so loanrangie! . 98 TDI DISCO lightly modded with more to come.
pootrol wrote:my last GQ was a manual which was great but ive now got a another GQ with an auto which im looking forward too once finished as ive thought for a long time it would be better control for 4bying.also without one hand constantly grabbing for the shifter i wont be spilling my beverage all over the dash while juggling steering wheel,gearstick and can at once..ive always said if you have an engine with enough torque go auto same for road cars.smaller capacity motors need manuals to move by ringing the p#ss out of them.same on the street,rice burners need manuals big engined cars use tricked autos.
Pootrol has brought up the main and most important factor in 4x4'ing.
You should always go for the option which will be less likely to spill your beer.
I've just purchased a new XLT dual cab ranger in auto, because the majority of it's life will probably be on the road, although i'm going to do my best to get out there when ever i can. So i was pretty glad to see that alot of people seem to prefer autos for offroad. I havn't had the chance to take it offroad yet, so not sure what it's going to be like, but for what i'm wanting to do i think it'll been fine. But on road, the autos used in the rangers and BT's are very good, standing start accellaration is unbeleivable for a small TD, the big stall (around 2500-3000) gives you it's optimum power and torque straight up, where as my 2.5 manual ranger can suffer a little if the revs drop, when loaded up. Another thing i found with the auto, is that it's manuallized, put it in 2nd or 3rd, and that's the gear it will start off in, and stay in.
carrot wrote:
You can push start an auto?? Could someone please explain in more detail? What gear, or just in "D" in high range (from "N," of course)? What's bump starting?
I've always heard that you can't push start an auto, so this is sounding good!
You can't push start many autos. apparently the trimatic can (?) and so can the merc box in the 300GD. Be aware that if you try this you risk damage to the gearbox. if your auto won't permit it. It is related to the position of the pump (i.e relative to the output shaft)
I am aware of a guy the the US that ran a TH350 behind triple transfer cases and 5.13 gears and apparently that would just bump start like a manual, but he had about 135:1 reduction before converter, so it won't take much to turn the motor over.
With "normal" gearing the procedure involves towing the car up to speed and dropping into D from N. lot more speed is required than in a manual, but that will depend on gearing etc. With very low gearing and in low range, it should work at quite a low speed.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
so i keep seeing the term 'bump start', and i get a mental picture of a bloke standing behind a 4wd and casually bumping it with his hip, at which point the engine turns over....
whats the dif between bumpstart and roll or tow starts?
[quote="Barnsey"]
Bronwyn Bishop does it for me.[/quote]
Most manuals, once warm, will "bump" start, - once the car is moving (at all) popping the clutch in will start it - generally, the speed doesn't need to be much over a walking pace. I used to be able to bump start my diesel hilux at ridiculously low speed.
Auto's generally require a "tow start" as I understand it - the slip inherent in an auto means the car has be moving fairly quick to get it to turn the motor over. I don't know that there is a set speed - it will depend on the converter and gearing.
The auto I referred to be "bump" started was only due to extremely low gear reduction. This created other problems, like being unable to stop the car with the brakes though....
Unfortunately, (or not...) there's VERY limited transfer case options behind a trimatic - they only came in Suzuki Vitaras. With some other parts (from OTT industries in Canada) , it MIGHT be possible to mate one to a hilux transfer case. I;m currently putting one into a sierra and I've made a short tailshaft adapter, so a vitara one could work with a divorce mounted transfer case like an MQ or Navara.
Steve.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
Thanks for all the replies, I'm trying to understand... Sorry, I'm a bit new to much of this terminology...
Trimatics = part of the GM auto transmission family (wikipedia)
It is related to the position of the pump (i.e relative to the output shaft)
Meh? Which pump? I feel stupid... heeheehee
Ok, I'd like to be able to understand all of this so that I can know which autos I can push start and which I can't, but if that's all too hard to explain to me then my main question is, can I push start my prado?
carrot wrote:Thanks for all the replies, I'm trying to understand... Sorry, I'm a bit new to much of this terminology...
Trimatics = part of the GM auto transmission family (wikipedia)
It is related to the position of the pump (i.e relative to the output shaft)
Meh? Which pump? I feel stupid... heeheehee
Ok, I'd like to be able to understand all of this so that I can know which autos I can push start and which I can't, but if that's all too hard to explain to me then my main question is, can I push start my prado?
Auto oil pump. The pump that moves the auto fluid round the box, making it work (very basic explenation there ). Without oil pressure, auto's dont work . Google the workings or an automatic transmission, you should find a few simple to understand diagrams that will help you get your head around it.
Layto....
[quote="v840"]Just between me and you, I actually really dig the Megatwon, but if anyone asks, I'm going to shitcan it as much as possible! :D[/quote]
carrot wrote: then my main question is, can I push start my prado?
No.
The only reason I stirred up the pushstarting thing was NAM's original point that you can't push start an auto, and, in some rare cases, you can.
Unless you come across a G wagen or a carby vitara that need push starting in the bush, assume you can't.
I wouldn't try it with a Prado. It may result in transmission damage.
Reminds me of some old school auto tech published in US Fourwheeler magazine about 15 years ago that you could slip an auto into reverse when descending a steep hill and use the accelerator as a brake. This was published with a proviso that it shoudl only be attempted with old/worn/loose autos.
Someone tried it with a brand new 80 series auto. It "bit" instead of slipped and the car rolled.
Steve.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
Haven't read the thread but my opinion is auto's kick arse in the bush, I would have disagreed before I actually drove one. They seem to soak up the bumps and ledges a little and keep traction, it is also one less thing to worry about.
My prado is auto and I love it in the bush, will have the hilux back next week with a commo V6 and shift kitted T700 and I bet it is even better being able to hold higher gears and not worry about stalling out or changing back with a clutch etc.
Manual had it's purpose but the autos hold their ground really damn well, love it!
[quote="fool_injected"]
I pity my brother when she is a teenager[/quote]
funny how over 90% of comp trucks are autos ey....
i prefer a manual myself, but you would have to be an idiot or live under a rock not to realise that in many situations autos are at least equal, if not superior to, manual vehicles when set up properly.
[quote="Barnsey"]
Bronwyn Bishop does it for me.[/quote]
I like to think manuals are for standing at the bottom of the hill watching the hard lines getting driven.
Really, it's horses for courses - my road car is manual, my 660cc sierra is manual, my Gwagen is auto and the last two cars I have built are auto. In a road car or a touring 4X4 - manual no worries. The harder the terrain, the more you want an auto.
Nobody who has ever seen a properly set up (and driven) auto work would ever say a manual is superior in hard terrain.
Steve.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
funny how over 90% of comp trucks are autos ey....
i prefer a manual myself, but you would have to be an idiot or live under a rock not to realise that in many situations autos are at least equal, if not superior to, manual vehicles when set up properly.
U cant compare a comp truck to your standard fourby....in comp trucks u are too busy with your hands to have a manual...but for a standard fourby u need a 5 speed manual...
funny how over 90% of comp trucks are autos ey....
i prefer a manual myself, but you would have to be an idiot or live under a rock not to realise that in many situations autos are at least equal, if not superior to, manual vehicles when set up properly.
U cant compare a comp truck to your standard fourby....in comp trucks u are too busy with your hands to have a manual...but for a standard fourby u need a 5 speed manual...
whats wrong with an auto that has 4 gears and a torque convertor which esentualy gives you a larger range of gearing anyway?
do you only steer with one hand whenever you drive the rougher stuff? its great to be able to choose the gear you want, but sometimes you just dont have enuf hands to shift when you really need to...
[quote="Barnsey"]
Bronwyn Bishop does it for me.[/quote]
funny how over 90% of comp trucks are autos ey....
i prefer a manual myself, but you would have to be an idiot or live under a rock not to realise that in many situations autos are at least equal, if not superior to, manual vehicles when set up properly.
U cant compare a comp truck to your standard fourby....in comp trucks u are too busy with your hands to have a manual...but for a standard fourby u need a 5 speed manual...
whats wrong with an auto that has 4 gears and a torque convertor which esentualy gives you a larger range of gearing anyway?
do you only steer with one hand whenever you drive the rougher stuff? its great to be able to choose the gear you want, but sometimes you just dont have enuf hands to shift when you really need to...
i'd rather select my gears so im in exactly the right gear i need...rather than let the auto jump in and out of the gear i want...
funny how over 90% of comp trucks are autos ey....
i prefer a manual myself, but you would have to be an idiot or live under a rock not to realise that in many situations autos are at least equal, if not superior to, manual vehicles when set up properly.
U cant compare a comp truck to your standard fourby....in comp trucks u are too busy with your hands to have a manual...but for a standard fourby u need a 5 speed manual...
whats wrong with an auto that has 4 gears and a torque convertor which esentualy gives you a larger range of gearing anyway?
do you only steer with one hand whenever you drive the rougher stuff? its great to be able to choose the gear you want, but sometimes you just dont have enuf hands to shift when you really need to...
i'd rather select my gears so im in exactly the right gear i need...rather than let the auto jump in and out of the gear i want...
Why do I NEED a 5 speed in a standard 4wd? I have had them and I prefer the auto thanks anyway. I can and do select my gears in the auto as required and don't have it jumping in and out of gear as you put it.
[quote="4WD Stuff"]
I haven't quoted Grimbo because nobody takes him seriously :finger: :finger: :finger: :finger: [/quote]
speeds are measured in metres/hour at peak torque.... I think they do 250m/hr or something stupid setup like this. Patrol42 probably has more info on this stuff though.
