my auto in the 4runner does NOT like the cold.

it does NOT like to shift out of first gear, and when it does its a good head snap. (but only the first time)

after it shifts the first time it does not seem to have any other shifting issues with any other "gears" till you get to OD.

for the past couple of times ive drove it on cold mornings it does NOT want to hit OD for a good 5 min or so.

after it hits OD the first time it has no other trouble shifting in and out either on command (via button) or on its own.

Neither shifting problems can be "coxed" to go away (ie shift early) by letting out of the gas. (but after we get "over the hump" then it will upshift like it should if you let off it in the upper rpms)

fluid level is good, and fluid is fresh within 1000 miles give or take.

suggestions/comments?

 

solenoids?

 

mine doesn't shift into overdrive until it warms up also. there was a thread about this a little while ago, i think its common on all A340H's to reduce the wear and tear or something...

 

I've got a 340F and when it's cold I have very similar symptoms to you, snap-on. Except mine seems to stay in 2nd instead of 1st, and then the first 2-3 shift is hard. It won't go into overdrive until it warms up for a few minutes. After that it shifts just fine.

 

Everyone that I've ever drove are the same way, I've been told that it is designed to do this so engine reaches operating temp quicker. Toyotas are not the only one that do this, the Jeep automatics do the same!!

 

You're experience is typical of the Toyota autos. They will not shift into OD or lockup until the motor is warm. The shifts from a cold start are typical as the tranny has to warm the fluid somewhat to operate properly.

 

Change your thermostat and see if it help, get the one at the local auto shop instead the one at toyota.

 

Just so the information here is more complete for anybody that needs it, the A340H will not shift into OD and the torque converter will not lockup until the engine coolant reaches a temperature of 70 degrees C (158 degrees F).

 

Please stay away from the aftermarket thermostats. From my experiences and the advice of other Toyota mechanics the aftermakets are trouble and that's not on just Toyotas but other makes as well.

 

flush or drain and fill?

have you cleaned the filter lately? ie. with the last change?

 

when i pulled the motor (and trans) it got drained, TC drained, and the filter cleaned yes.



i guess i need to work on wireing up the switch for the electric fan in the morning so it isnt running full blast. i suppose that would be a good project for this weekend.

 

That directly contradicts everything everybody always says about toyota thermostats.

 

From my experience, the aftermarket thermostat work better than the toyota thermostat, right now I am using the toyota type thermostat and it take longer to shift than the aftermarket I use to use, but without one it will not shift to O/D. Also try using Redline Dexron II.

 

Guardian, that is terrible advice. What are the "best" plugs? Autolites? Champions? Gimme a break...please qualify your claim that the aftermarket thermostats work better. There is a reason your truck is not getting up to temperature w/o a thermostat. Please research before you make misleading posts.

Snap-0n, my truck will not shift "nicely" until the water temp comes up to about 160*. I though it might be related to tranny fluid temp as well but it is not. My trans can be 100* or 260* and it shifts darn near the same.

 

[hijack] Any photos of where you placed your sender for your trans temp?[/hijack]

 

I don't have one handy but I "T'd" the line coming out of the transmission BEFORE it goes into the stock radiator cooler, from there it goes into the auxillary cooler. I ran it this way to give the highest reading possible. I routed through the factory cooler to help heat the ATF in the winter time. I've got an aircraft style silicone baffle to block the aux cooler in the winter.

 

The theory about the temp needing to be a certain temp , sounds pretty good.
If you want or it doesn't hold true for your circumstance, i was having shifting problems in the 90. It felt like it was hanging up in between gears and i did not have overdrive. Tossed in a can of Sea Foam's tranny cleaner and must have cleaned out my obstruction, cause now it shifts and drives 1k times better.

 

Just so we don't get confused here, this is not a theory... it's a fact, and it's built into the logic for the transmission. As I mentionned above, the A340H will not shift into OD and the torque converter will not lockup until the engine coolant (as read by the ECT sensor in the coolant bypass at the rear of the engine) reaches a temperature of 70 degrees C (158 degrees F).

Now, nobody's saying that it's the only problem here, because it would not explain the rough engagement between first and second gear, but having to drive 5 minutes before O/D will engage is normal.

 

I know.

A theory is based on proved facts.

hence the comment, and also the reason i posted my comment about the cleaner. It sounded like he needed to get it up to temp first. but something also sounds like it is sticking because of the shift harshness.

 

Good point.