[ALWilson]

Auto trans, A340E, v6 1997 T100

This problem started a while ago,

One month ago as I drive away from the house in the morning the trans acts strangely and won't shift up to 2nd gear, it catches my attention, then shifts smoothly from there on out. No problem shifting for the rest of the day. Several days pass, no difficulty with the 1-2 shift, then after sitting overnight, it won't shift 1-2 until it's warmed up. Now I just let it warm up, temp gauge up to midway, and she shifts like out of the show room.

I want the problem solved so I talk with my local mechanic he recommends taking it to the dealer; they're the experts and all. I follow the advice. After a day in the shop the service writer, calls.
"Mr. Wilson, you need to have the solenoids replace, valve body overhauled and it will cost you 1,300.00" I gasp, ask for time to think it over and hang up. I debate with my self and figure, go ahead and fix it, it's a good truck and a bad transmission can happen. So I call the dealership, negotiate the price down a bit; feeling smug I authorize the repair. Later buyer's remorse sets in but I rationalize," it's a good truck and you'll keep it a long time. They know what they're doing" and so on. I'm told it needed to stay until the end of the following day to complete the repair. Late the next day the service manager calls, "we can't find anything wrong, the solenoids work fine, and we don't want to go forward with this repair." Have you thought about swapping out the gear box? I'm shocked, what are they telling me? I change my mind, instruct them to stop work and put it back together. " We'll have to charge you 86.00 for the diagnostic work, I say. I don't like it but, put it back together and I'll pick it up."

Since then, at two independent shops, first shop's free diagnostics found; no computer codes and vehicle is safe to drive, they did not drop the pan. Second shop: kept the truck overnight, test drive in the morning showed the 1-2 shift delayed until engine reached operational temp, then no problems, codes or any thing wrong. Except they dropped the pan, now they say brass in the pan, or maybe it's babbit and the entire box should be rebuilt. I thank them for the observation and cautions that it will fail catastrophically and so on. I say, I'll take my chances and when or if it does fail I'll invest in it at that time. For now I'll let it warm up and drive it. No kidding after the initial shift it drives as if it came off the dealers lot, no slip, sounds, clunks, nothing, runs and shifts great.

Now I'm not too sure if you have an answer for all this but I'm really interested in finding out why it would behave the way it does and if there's an easy, or at least do-able fix for the problem.

I look forward to your comments and answers.

Al

 

[texas12]

Have you tried manually shifting? Start out in low and then shift to 2. I would still suspect the 1-2 solenoid in the transmission. I know on my '86 4runner it can be changed without dropping the transmission. Not sure about yours.

 

[Punisher]

I know the problem... I have an ae92 corolla.. '89 with an automatic 4spd.. When it is cold and shifts out of 1st into 2nd it will jerk.. when it warms up it isn't nearly as bad.. but then all the rest of the gears work fine.. whether I am beating the piss out of it.. downshifting into second to gain power or whatever.. no problems. It has done this for quite a long ass time now.. and even at one point the tranny wouldn't like work.. it hung in gears and barely put any power down to the wheels. The next day.. it worked perfectly.. lol.

I'd have to agree with your thoughts, just run it till it croaks. WHich I doubt it will. Check out your local junk yards and stuff.. see how much a rebuilt tranny would cost.. pick one up when you are ready and just keep it on hand if anything should happen. Shouldn't cost more than a few hundred dollars.. like 500-700 I'd imagine.

Best of luck to you!

 

[ALWilson]

I agree they are tough transmissions but, it such a nice rig and this is small thing, letting it warm up before driving, but if there's an easy fix, like changing the 1-2 solenoid, which I've been told can be done "under the truck" I'd go for it.

What about the valve body, is it a big job to change it out?

Thanks

 

[ALWilson]

Have you tried manually shifting? Start out in low and then shift to 2. I would still suspect the 1-2 solenoid in the transmission. I know on my '86 4runner it can be changed without dropping the transmission. Not sure about yours.

Hello

I took your suggestion; this morning when I drove off I put the selector in 1st drove for a few yards, about 2k on the tach and shifted up to drive, the gear box shifted into 2nd and so on. Next stop, a 100 yards or so started off in D and the gear box shifted fine...:thumbup:

I'll need to check this a few more times but if it works every time do you know which solenoid would need to be changed?
1 or 2 ? Have you solved this problem in your gear box?

Thanks

 

[dx-r]

Maybe the 2nd gear clutch pack in your trans is worn out. Have you checked your trans oil? Does it look dirty and smell rancid?

Removing the valve body is not that hard but it's a messy job. Basically you would drain the tran oil, remove the pan, remove the trans oil filter/strainer, remove the bolts holding the valve body then lower the valve body enough to disconnect the throttle valve cable then the valve body should come right off.

 

[ALWilson]

Hey, Dx-r

The fluid is in fine shape, clear and red. Thanks for the thought on the clutch packs. But when it upshifts to second there's no slipping or sounds or anything out of the ordinary???, it just shifts late, that is until the temp gets up a bit off the pin. Thereafter it shifts fine.

What grabs me is how my local temp could change anything in the flow of fluid? I live in So. Fla and the overnight temps will warm a can of beer but not change viscosity of something like A/T fluid. Be that as it may, first shift in the morning the trans won't shift out of first until after it reaches operation temp. If I let it warm up before driving off, It's no problem.

I'm wondering about the #2 solenoid, from what I've read it's got to open to allow the 1-2 shift, now how would temp effect a solenoid or its ability to open and drain that side of the shift valve? Lets say the solenoid opens, drains the top side, but sticks then the fluid won't go through the right passage to the second gear brake pack?? Man I wish I had a clue.....

Anybody want to chime in?

:hammer: :hammer:

 

[redfox435cat]

hum. my 04 does this on 2-3 when its cold. after that its fine.

 

[bobad]

hum. my 04 does this on 2-3 when its cold. after that its fine.

My 92 does that since brand new.

It's a small annoyance on cold mornings until it warms up. If I lived in a real cold climate, it would be a problem.

 

[ALWilson]

Thanks bobad/redfox

I agree it's just a little thing in an otherwise great rig.

From what your both saying it stay the same, and doesn't get any worse?

Thanks again:chug:

 

[bobad]

Thanks bobad/redfox

From what your both saying it stay the same, and doesn't get any worse? Thanks again:chug:

Mine hasn't changed at all in 12 years. I wish I would have had it taken care of while it was under warranty, but it really is a minor aggrivation.

Your problem could be a little different, so your experience may turn out differently.

 

[jeffs94]

It sounds like a throttling valve problem, wont do it when its cold but when its warm it shifts like a dream. A good valve body cleaning would probably find the problem, gummed up throttling slots i suspect or lots of clutch pack residue plugging up the 1-2 shift circuit orifices.

 

[bobad]

It sounds like a throttling valve problem, wont do it when its cold but when its warm it shifts like a dream. A good valve body cleaning would probably find the problem, gummed up throttling slots i suspect or lots of clutch pack residue plugging up the 1-2 shift circuit orifices.

Sounds reasonable for an older tranny like the OP, but mine did it right off the lot.

 

[ALWilson]

Sounds reasonable for an older tranny like the OP, but mine did it right off the lot.

Right off the lot? Are you sure you're not experiencing the " no shift in OD feature" until the coolant temp reaches a pre set temp?

I use to experience that and was concerned but learned from the owners manual that it was a built in feature.

My symptom, on further investigation is not temp related, i.e. it will not shift from 1st to 2nd after sitting for 8 to 12 hours. But letting it idle for a time or starting off in L and then running up the rpm to 3k the upshifting with the shift lever will make it up shift.

But after the first upshift, smooth as silk.

I'm leaning towards the valve body problem, sitcky or dirty 1-2 shift valve, but don't know how to proceed.

Aftermarket trans medics, Synthetics, upgrade to re-built valve body, hot footing it around in second gear, plugged strainer????

Or learn to live with it? Not really an option, cause it's such a nice truck in all other regards.

Thanks

 

[ALWilson]

It sounds like a throttling valve problem, wont do it when its cold but when its warm it shifts like a dream. A good valve body cleaning would probably find the problem, gummed up throttling slots i suspect or lots of clutch pack residue plugging up the 1-2 shift circuit orifices.

I agree, but how to proceed? Drop the pan take out valve body, put on bench and then what? It looks like a pro's job to clean, reseal, etc... Then if I'm going to the pro's to rebuild the VB why not get one of the "modified" performance units and then on to Turbo Charging or Super Charging??? I can hear my wallet scream.

DIY type project? I'm a fair mechanic, but of the shade tree type with no shop, lift ,or the other things that make life easy under a truck.

Thanks

 

[jeffs94]

I agree it sounds strange to have this problem right off the showroom floor....could it be a safety feature until the tranny fluid gets up to the correct temperature? I dont recommemd removing the valve body until you are 110% sure you know where the gear selector needs to be....removing the VB without knowing this could lead to a whole list of problems up to and including removing the tranny and a complete teardown. I'd definitely find out from toyota or check the factory service manual BEFORE attempting.

 

[400ex rocks]

No shift problem

I live in canada and it is much colder which agravates this problem alot more. I have a 2001 tacoma that did this. The problem was that the Neutral start safety switch would collect moisture over night and until you drove it far enough to heat the transmission and dry out that moisture it wouldn't shift. I put a new one on and it took care of it . My dealer told me that they have done alot of these as it seems to be a flaw in toyota models. The switch was $210 plus 1 hour labour. You could also try a parts yard as they go for about 40 bucks there.
Good luck I hope this helps.
Rob