Running a 2c with auto3speed + o/d in a 94 caldina wagon. If you Brits arnt familiar with that name, same as corona(WOT??). Anyway, small/med family wagon. It locks off at 70km/hr in 4th. Trying to climb a hill at speed, have to drop back to 3rd which is screaming, gas off to 4th then she goes straight into lockoff instead of slipping in 4th till 100km/hr when engine rpm would better suit lockoff. Quite surprised toyota got this box/engine match, spoilt an otherwise economical family wagon. Is there a speed sensing device, can I can manually insert a manual overide switch, or, is road speed detected inside box with no way of overiding lockoff at 69km/hr. The issue is hills, and having to slug up them because of this auto configuration. If I could have slippage in 4th till 90/100 km/hr I could maintain/increase speed up hills instead of now having to predict and run at them with speed or suffer embarrising speed drop to 60km/hr as screaming in 3rd is destructive. I took the auto in for a service when I bought her 3yrs back, when I mentioned this issue and asked these questions they blinked for awhile, a prominant auto specialist didnt know. Toyota seemed to have matched this auto to the wrong engine? So, are we stuck with this unusual design fault, or is this a little screw adjustment I dont know about, and will kick myself for putting up with this for so long... Cheers Frank

- (#14019) frank, 2 Nov 04 13:03

Uh, no, the Caldina/ Corona would be the Carina in the UK.
So that's a front wheel drive transaxle, then. Is the tranny pressure controlled (it's got a kickdown cable) or electronic 9a TPS and a bunch of solenoids.

The Townace is RWD with an Aisin A40 series mechanical/ pressure controlled tranny. The only solenoid is for o/d. So we probably can't help much. Now, if it is a pressure- controlled tranny, you might adjust the kickdown cable a bit either way and see if there's any effect. Most of the system relies on a pressure signal from the governor to operate, you could strip it all down and alter it, or you can change springs inside the valve body too, but that's a big job.
If it's an electronic tranny, there's ways and means but pretty complex to explain.

I'd say a non-turbo 2c in a Carina shell is underpowered. Perhaps Toyota have tuned the tranny to let the engine rev out in each gear to compensate?

Give me the model code of your car and I'll try to find if there's any changes/ updates on the tranny...

- (#14019) David Miller, 2 Nov 04 16:19

Our speed limit is 100km/hr, even on our best roads, so shes underpowered in regard to overtaking, nearly adequate otherwise. Letting o/d rev out until lockoff would be nice! but this is not what Toyota have done here. Lockoff ALWAYS occurs at69km/hr when in o/d. If in 3rd screaming at 80/90 km/hr and you gas off to enter o/d in will enter o/d for a second then lockkoff. then being in too high a gear for the hill you drop it back to 3rd, screaming again, you reduce speed and be satified at only 60/70km/hr for the hill. It could climb in o/d slipping at around 80/110km/hr (engine power would be okay, ratio too) but lockoff at 69km/hr prevents this. O/d slipping is currently under utilised as lockoff at 69km/hr is set too low. Kickdown I think is press/mech(cable to throttle linkage on fuel pump), only wires to tranny at select linkage on box and o/d solenoid I guess. my recokoning is the device that lets lockoff know its now 69k, time to lockoff, if i could overide it or change the speed it switches at.... model KB-OT196V-DXPNS FRAME CT196-5008239 TRANS/AXLE A241L-02A Kickdown adjustment does not alter lockoff begining at 69k. If lockoff initiation occurs inside box, I think I'm stuffed. If its initiating device is a wire from speedo we may be able to put a switch in circuit and override it when slippage in o/d is prefered. Ideally it should slip till around 100k because, even on the flat and working up to 100km/hr, as soon as lockoff happens at 69k, acceration decreases dramatically, and excessive load is placed on the engine. Makes it a bit of a lemon, though I have modified my driving to suit and got over my initial disappoitment ....until now.. Cheers Frank

- (#14019) frank, 2 Nov 04 17:33

Bugger, Typed a reply and the server crashed out...

Anyway, your 241L is a hydraulic tranny. From the info I have, you might want to look at removing the governor and playing with it's spring and weight. It looks like it's in a housing above the diff and so might be easy to remove. The other line of attack is the valve body.

But to go any farther you'll need a manual. I sourced a manual for the A40 in the townie from a place in the US. They list one for the A240, but it might be out of print now. Search for ATSG.

- (#14019) David Miller, 3 Nov 04 14:13

Thanks David. I got on the telling bone to some auto trans specialty garages, full page ads in the phone guide too. One, said lockoff was temp controlled, sender on the radiator, after promptings from me of disbelief, corrected to say taking the pan off and valve spring alteration. Another said it was solenoid operated(told him it was a mech box) and a switch with resistor in line same impedance as solenoid to fool computer. I'll try Toyota nz and let you know what they say. I hardly deal with cars, except an interest in my own maintenance-- usually cause I hate being screwed around by dumbasses at garages. This is starting to make a good story, or maybe God doesnt want me to own cars...... I can see her point, they appear to make some people stupid. The board of knowledge excloded of course. Thankyou Gentlemon FRank

- (#14019) Frank, 3 Nov 04 15:18

The o/d solenoid only enables the rest of the o/d circuit. You still want o/d, but you want to affect when the lockup clutch is engaged. That's a balancing act between line pressure and the various valve springs in the lockup control section. Both throttle position and road speed affect line pressure in various parts of the system.
You might try setting the kickdown cable WAAY too tight- just make sure you still get full throttle movement- if the tranny thinks the engine is under full load it'll hold the clutch open to a higher speed. If it doesn't, perhaps the tranny actually has a fault?

- (#14019) David Miller, 4 Nov 04 01:34

No matter what throttle position, always lockoff at 69km/hr or, if just to o/d from 3rd, immediately upon entering o/d.

- (#14019) Frank, 5 Nov 04 00:40

Hmm. If it was a townie I'd say it's faulty. The townace tranny will slip gently into lockup at (working from memory here, haven't driven one for nearly two years...)around 40mph. At full throttle it'll hang on to 3rd until about 65mph befor slurring a change and then slurring the lockup on.

Do you notice ANY change in gearchange characteristics depending on throttle position? I'm wondering whether the kickdown cable is broken internally, or the valve it attaches too is seized?

- (#14019) David Miller, 5 Nov 04 02:01

David Going by your townie changing description, my caly would be the same. My arguement is: this configuration is not ideal for performance. I dont mean racing, just normal driving. When accelerating up to 60mph or so, the acceleration slows dramically when lockup occurs. The engine even does a shudder on its mounts, as the load of lockup is too early, puts an excessive load(wrong gear) on the 2c matched to this auto setup. Its just a design fault in my book. My kickdown functions correctly, I've altered it before with no change to lockoff at 69km/hr. Consistant changing occurs, the box is in good working order. The designers just screwed up, I reckon, and I was hoping to modify this mistake of design. More slippage in o/d before lockup would improve the driving all round. Its a schoolboy error in my book, unless a previous owner replaced a box or motor of a slightly differing match, creating this problem. I'll phone some owners/sellers this weekend, see if their's are the same.... let you know

- (#14019) Frank, 5 Nov 04 03:06

...But lockup is there to improve mpgs by removing slippage losses.
I know you've readjusted the fuel screw, but are you sure the motor is performing as per factory?

Remember that a diesel is most efficient around it's torque peak, usually around the 2k rpm. There's also no sense in letting the engine exceed maximum power revs (4k-ish).

- (#14019) David Miller, 5 Nov 04 11:04

I'd say the valves are slightly in need, rings getting tired maybe too, but it still shifts like a lemon. If only a manual override of lockup was fitted, hills would be less embarrasing. After purchase 3yrs back, i changed 13" wheels to 14". Better, that shudder at lockup says it all to me...

- (#14019) Frank, 5 Nov 04 16:43

Of the 8 owners I contacted today none were familiar with lockoff or when it occurs. Some will probably become conscious after my calling and query, though i doubt i'll know as i've had a gutsfull of this. Many hours now. PS tyre cicumference of 14" (low profile) only 5% more than 13". So, no, my wheels arn't too big. DAVID I agree with your arguement that lockup is there to reduce losses, a manual overide to extend slippage in 4th would also reduce loss of momentum at hills, reduce loss from strain on moter caused by direct drive occuring at too low an rpm, and reduce loss from overreving a deisel in 3rd gear. You say there is no sense in revving beyond 2000rpm, yet earlier post a description of your use of a townie 2yrs previous in a manner I would call reving out. Its okay though. Thankyou for all the kind attention gentlemen. I'm off to blow some whistles in another world where theres no doom and gloom. thanks F

- (#14019) Frank, 6 Nov 04 00:21

Nope, I didn't say that. I said no sense revving beyond maximum POWER @4000...

At this stage, if I were you I'd probably want to strap the car to a dyno to confirm that it's HP output is approaching it's rated value and that power and torque curves have sensible shapes. Perhaps cam or pump timing are off. Anything which affects timing will affect the shape of the power curve, and that might result in the "mismatch" you feel.

But seriously though, have you driven many automatics? Your description of what it does sounds like many I've driven, including my present Grand Vitara TD- which has a bang-up-to-date electronic tranny. You say it's rolling into lockup on a light throttle at 69kph. Sounds OK. And under heavy acceleration, it holds onto 3rd until 100kph before dropping into 4th and lockup almost simultaneously. Again, 100%. Perhaps you're asking the tranny to enter a regieme that it has no need for, assuming that the engine is functioning correctly?

It'll be spanners out to make any changes to the tranny, no doubt.

- (#14019) David Miller, 6 Nov 04 00:43

David Yes, sorry to misquote you. A little frustrated cold calling people and asking them about their auto tranys... And yes everything is 100% in the manner it shifts, the engine uses no oil and has minimal clatter for miles travelled, though power is probably down from factory. However, expenditure Vs vehicle resale value would prohibit further investigation... She runs like a dream...and most test drivers would agree. Hopefully, the couple driving 2hrs tomorrow to come and buy it will agree. I guess I'm a little hung up on this mainly because, as my friends tell me, I'm very light on the throttle. I'm not into reving motors at all. However I'm a long way from my chinese girlfriend, whose slugged her 999cc toyota starlet around for so long she has got severe carbon buildup, the pinking prompting me to get her to change to higher octane fuel, retard ignition, and for a couple of weeks let me cane it on the highway/motorway, going from her normally 40mph cruise, to 60mph, never speeding of course.(yip, no tickets for going too slow in nz!). I might be a featherfoot, but now and then I'll give them a good hill climb at speed, or high speed night trip on an empty road. I've never ever had to open up an engine though, and in the past kept very high milage cars going longer than expected. The spanners stay rusty. And no, this is my first automatic. I have driven many though, being an ex cabbie for a while in Sydney, and from a company pool when I was servicing production equipment. That was all years ago, I'm sure the modern auto trany has space technology in comparison. AT's are a bit like remotes, once your got used to them.... Next week my Toyota Coaster 6m bus running the 4.2 landcruiser engine should arrive from Japan. '92 for $15000 landed and on road. I'm fishing this summer, renting the house out. I know, mutter mutter, you've got winter. I'll have a rotten time, probably.

- (#14019) Frank, 6 Nov 04 05:16