[zookster666]

im currently building a 1.6 and thought about using the vitara 3 speed auto

I just wanted to know.

Has anyone put one in?
Are they any good?
What is involved?
how would i mate it up to the sierra transfer?

cheers

[joeblow]

yes
no
lots
adaptor plate with bearing.

[Gwagensteve]

They work quite well so long as you can get them geared correctly. That's a bit of a catch because without an overdrive, you'll need quite tall diff and transfer gearing to make it work.

It's much easier to fit a 3 speed than a 4 speed- It's quite possible to leave the transfer in the stock position and still have a useful jackshaft.

The 4 speed is a better gearbox, but its length is a major hurdle, not to mention it's an electronically controlled box and therefore needs some amount of control/wiring to get it to work properly.

The car I built with a three speed runs a baleno 1.6 EFI (coil pack) 3.9 diff gears, a series 4 rockhopper transfer and Q78 swampers. (35.5") It runs 3900 rpm @ 100 km/h and has lots of low range - it engine brakes quite well in first gear and has plenty of power and gears to generate wheelspeed in mud and crawl on steep stuff.

Setup with 4.9 transfer gears, a trimatic sierra is still highway drivable on a 31" tyre- with WT diff gears (3.7) highway cruise is at 3863 rpm- about the same as a stock jimny.

Crawl ratio with this setup is 46:1 x about 1.8 for the converter - plenty for a 31" tyre. The real issue is it's not feasible to run less than a 31" tyre - highway revs will just go too high, even with a standard transfer case (and the crap gearing offroad that entails)

The adapter plate is quite easy to make - the output of the auto is the same spline as the back of a sierra manual so a sierra yoke slips straight in. I used an off the shelf bearing and a sierra gearbox output shaft seal.

Here's a photo installed.



Transmission tunnel work is required, even with a 2" body lift, but it's not that extensive.

Steve.

[Damo]

Are these really the same guts as a Trimatic? I've always heard they are but don't know for sure. Plenty of go-fast bits for them if that's the case.

[zookster666]

Thanks for that steve i run 31' tyres 3.9 diff gears and 4.16 transfer gears so it might not be very good at high speeds considering i wont be trailering it.
Is it possible to get an overdrive gear installed?
i want to stay away from bodylifts to keep a low center of gravity how much more tunnel work will be needed?

cheers

[datso]

Trimatics with the right oil and modifications are used in all applications and are almost bullet proof. Plenty of idiots put the wrong oil in and call them temperamental and hence the traumatic label came to be know when castrol no longer made dexron 2 available for them and all kinds of oils where tried.
You have to use the correct oil (now dexron 3) and there are a few tricks to make them almost bullet proof. I got one from a holden gemini which are made for a 6cylinder also and has no unitary transfer case unlike the vitara version.
Just use the vitara bellhousing, a gemini box and your choice of transfer case even a hilux will be a better option. Mine has a fully manualised kit and had some holes enlarged and stronger band replacements. A good oil cooler is another must when abusing these boxes. Very happy with mine.

[Gwagensteve]

Yes they are a trimatic. They weren't just used behind 6's either - they were run with up to 253's in Kingswoods and early commodores. There's plenty of tech on making them very durable (that's not the same as strong - there's seal upgrades etc that make the trans longer lasting than stock without actually adding strength.)

I'm not crazy about the idea of manual valvebody without a reversed pattern, apparently something not available for the trimatic - but thats just a preference of mine.

There was an aftermarket overdrive available for the trimatic - I've seen on a trimatic behind a 202 holden motor from NZ, but judging by the length, I'd say it would be far too long so there's no advantage over an AW-4.

There is also a lockup torque converter version (the TH180-C) used in the US, even on some vitaras, but apparently the locking solenoid is failure prone so there's no advantage there.

Yes, donor parts can come from any trimatic, however, saying "just whack a vitara bellhousing on a gemini trimatic" is a bit misleading, as the output shaft would also need to be swapped to a vitara one to reduce the length enough to make it worthwhile, and considering that to so that you'd need a whole vitara trimatic to get those parts, why not just fit that?

Some of the opposition to the trimatic comes from no overdrive (a limitation, I admit), but also the tallish first gear and loose converter- the trimatic has a 1.8:1 converter ratio, the AW-4 is 2.4:1 - but the hassles of trying to get the length of the AW-4 into a sierra just makes it less attractive for a SWB. It can be done, but the chances of ending up with a trouble-free installation are much lower.

Additionally, if you have a poorly geared and/or underpowered car, a trimatic will be terrible. I'm aware that some have been used behind corolla 3K motors for example, and they are horrible slack things to drive. That's not the case behind nearly 70kw and 130Nm with a Baleno motor .

I've also installed a jimny auto into a sierra and with a large cooler it works well, but it is not a transmission that can be readily strengthened, all repair parts are ex-suzuki, and it has a very small converter which seems to make it a bit "grabbier" offroad, so harder to modulate around the stall speed. They also need tranmission tunnel mods.

Here's some photos of the tunnel mods required with a BL. Yes, more would be required without a BL for sure - I'm not entirely sure how much. Not a great deal more IMHO.









Zookster - here's my gearing info for your proposed setup.

tyre diameter in inches 31.00 inches
1st gear 2.54 :1
top gear ratio 1.00 :1
Transfer case high range ratio 1.55 :1
Transfer case low range ratio 4.16 :1
Diff ratio 3.90 :1
revs @ idle 750.00 rpm
revs @ peak torque 3500.00 rpm

Desired cruising RPM 3500.00 rpm
Speed in km/h 85.95 km/h

On road data
Cruise RPM @ speed
Desired speed in km/h 100.00 km/h
rpm in top gear@ 100km/h 4072.33 rpm
Off Road Data
Crawl ratio 41.21 :1
speed@idle in 1st gear 2.70 km/h
speed @peak torque in 1st gear 12.61 km/h

This is from my gearing calculator, that doesn't take into account converter ratio - your "real" crawl ratio would be equivalent to 74:1 in a manual so your speed at peak torque in 1st gear would be 7km/h

I'd agree 4072 rpm is a bit high at 100km/hr. Anything under 4K should be liveable though.

Steve.

[zookster666]

Thanks for the info guys it has helped me alot.
All i need now is to work out what to do next. As i said i still need to be able to drive it comfortably at highway speeds i will speak to a transmission specialist before i go any further

cheers

[datso]

I wrote the last message at work and had to hurry but thanks Steve yes its not a matter of just whacking the gemini box on you will need to get this done right by aligning the pins and will need a centering tool to get the vitara bell right also a donor vitara 3 speed helps!
The input shaft change was inc. in my rebuild as I had the Gemini tri rebuilt using the Vitara TH-180 as a donor for bellhousing and any other bits that it needed. The full manualising kit is not a strengthening mod but I like to have full control of the changes and it helps keep me awake.
I needed the transfer case rebuilt and decided to go the Gemini box and a Toyota liteace 4x4 diesel transfer case which is good for the freeway and for light duty offroad. The hilux TC would be better suited for heavy duty off road but they supposedly the same design.
Youll also need the right Gemini box with the linkages on the drivers side.
I got my Vitara auto from a friend and the Gemini was free from a Gemini forum member.
I had the mounts custom made and hammered the tunnel like a mad man and welded some plates where I split the metal open but in the end I can get a trimatic cheaply re-built or a complete one easily.

On a side note do not read if its insulting suzuki loyalists I ran into an owner of a Lada Niva in Albury (big Dutch dude named Piet) which had a Fiat twin cam engine and converted the car to 2wd with no transfer case using a gemini box (originally a sohc fiat from factory). He said he enjoyed drifting on dry back roads and was going to turbo it next. It had twin downdraft webers and sounded and went awesome. Ive been considering the Fiat engine recently as I can get the running gear from a damaged Fiat spider and a 16v efi engine from an import. Its alot of stuffing around but the fiat twin cam engine is bullet proof and would make a killer street setup with rwd only since its becoming more and more of a Tar queen rather than dirt muncher.

My understanding is that the 4 and 6 trimatics are a different compared to the V8 trimatics with the v8 versions having more clutch plates.
Also Toyota K series engines never used trimatics they have their own design.
Ratios vary depending on what car they where fitted in eg. Peugeots, Chevs (Opel, suzi, Pontiacs, holdens) Rovers etc.

[twitchy]

speaking of which does anyone have a spare Vitara 3 speed????????????

[2stroker]

Sorry datso but Gwagensteve is correct after the demise of the toyoglide trimatics were common in a number of 3K and 4K engined corolla's in the late 70's early 80's .

Gee we have become spoilt, I can remember when a 2 speed auto was the ducks guts, then we had to have a 3 speed, now it has to be 4 or 5 speed with lock up converter etc.

Zookster666 if you are really keen to go auto why not forget about the 1600 Suzuki engine and repower the vehicle with something that comes with a decent auto instead, then your only specialty machining is a custom jack shaft, everything else can be done in house.

[Highway-Star]

twitchy wrote:

speaking of which does anyone have a spare Vitara 3 speed????????????

I know a wrecker west of Brisbane that had one (whole Vitara with 3spd auto, minus engine). Not sure its still there though, was a while ago I saw it.
Can try them if your keen anyway:
http://www.ipswichspareparts.com.au/

[datso]

Thanks 2stroker, Toyota K series and GM box wow

[Brett]

so does that mean you could put a vitara transfercase on the back of a gemini auto?

you could runn a piazza turbo, auto and duel cases.

[atari4x4]

Brett wrote:

duel cases.

are they 2 transfer cases that are fighting each other with swords?

[Saam]

nah you put an engine on either end and join them together, the one which doesn't explode wins

[Trojan]

atari4x4 wrote:

Brett wrote:

duel cases.

are they 2 transfer cases that are fighting each other with swords?

No, you'll find one sitting on a swinging chair on a verandah and the other wearing glasses leaning against a car.

[twitchy]

Highway-Star wrote:

twitchy wrote:

speaking of which does anyone have a spare Vitara 3 speed????????????

I know a wrecker west of Brisbane that had one (whole Vitara with 3spd auto, minus engine). Not sure its still there though, was a while ago I saw it.
Can try them if your keen anyway:
http://www.ipswichspareparts.com.au/

Been there & no go unfortunately. Mate at GDM Wreckers found one for $800 in shit condition. looks like I might have to go Traumatic from something else.

[zookster666]

I thought about different engines but i have the 1.6 already and have stripped it down to put all new gaskets in it and i want to keep it as simple as possible.
how much longer id the 4spd compared to the three speed
alternatively i can get an auto out of a 3k corolla for free this might be another option.
cheers

[kenn]

Go the four speed , it's worth the extra work..JMO.

[twitchy]

Can a 4 speed auto be used with a carbie engine???????????????????

[kenn]

You have a point there!

[Jester]

twitchy I know im the other side of the country but in the next few months I'll be pulling the 3 spd outta my vit to do a manual conversion, It will need an overhaul so i wouldnt ask much for it though freight would be the killer. If you'd be interested i could organise it when i get to it though first it needs to get on the road and get my hands on a manual box and goodies

[twitchy]

Thanks Jester, will be easy enough for freight as I have a friend in the right industry.


Or maybe I should just go back to the original idea of Isuzu diesel with auto?????????

[Gwagensteve]

twitchy wrote:

Can a 4 speed auto be used with a carbie engine???????????????????

Yes, but you'll have to be reasonably capable with some wiring.

All gears in the AW-4 except Park, reverse and neutral are selected electronically. Apply power to the right solenoid and it holds that gear. I don't think it would be possible to get automatic shifting though., so you'd have the equivalent of a full manual valvebody.

The AW-4 is 130mm longer than than the 3 speed from memory. that basically means there's no jackshaft (at all) if installed in a sierra with the transfer case in the stock spot.

I don't believe there's any real scope to shorten the tailshaft on a SWB sierra, so the AW-4 isn't really a viable alternative unless the sierra transfer is hard mounted to the back of the gearbox. That's possible, but has been stuffed up plenty of times too, and is a massive amount of work.

Steve.

[joeblow]

Gwagensteve wrote:

twitchy wrote:

Can a 4 speed auto be used with a carbie engine???????????????????

The AW-4 is 130mm longer than than the 3 speed from memory. that basically means there's no jackshaft (at all) if installed in a sierra with the transfer case in the stock spot.

there is plenty shaft left, have done quite a few with just the AW4 and t/case in original spot.

Gwagensteve wrote:

I don't believe there's any real scope to shorten the tailshaft on a SWB sierra, so the AW-4 isn't really a viable alternative unless the sierra transfer is hard mounted to the back of the gearbox. That's possible, but has been stuffed up plenty of times too, and is a massive amount of work.

Steve.

once again, there is plenty scope to shorten the rear shaft. i fit those autos to dual cases in shorties and the rear shaft is still longer than factory TJ rear.

the buildup thread on TABS hardtop will show this once we update it

[kenn]

I've got one in my LJ so it cant be that hard to do in a Sierra.
Just wasn't sure about the wiring bit with the carby motor.

[twitchy]

Looks like I might just have to get a 4 speed then, I know a good sparky so all should be well.

[zookster666]

i might be able to get my hands on a 4spd i can take it off the road for a while to fit it once i move.
im pretty good with wiring so i should be right ill try to do a thred on it once im ready to do it