Stelah Won’t Shift Into Overdrive/Forth Gear (urgent) (1 Viewer)

[tracknod]

Hello all,

So I’m on the road, 4000 miles from home with the family and have run into a problem. My supercharged 99 has decided it doesn’t want to go into fourth gear. YES I MADE SURE THE OD BUTTON WASNT PRESSED!

Right now I’m in Forks, WA. The problems started after I left the FJ Summit in Ouray headed to Portland crossing Utah pulling a 2400 lb trailer. On my scan gauge on one pass, the ATF temp got to 221 but no lights ever came on. About an hour later is stuttered going into 4th then it would drop back to third. All while the temp was reading 178. We stopped and let it cool and all was well.

Now, while I was in Portland for work my wife went and had the fluid changed at a dealership and they said all was good and it didn’t need a flush, but they did it anyway. I’ve check the fluid levels and all are good.

My problem is that now it won’t shift into 4th so I am stuck at 60 mph at 3000 rpms in third which is TERRIBLE son MPG and I have 4K miles to get back to Florida.

Does anyone have any suggestions on what I should do?

Thanks in advance!

 

[flintknapper]

What does your ScanGauge say your coolant temperature is (needs to be 130°F or above) or the transmission will not shift into overdrive.

IF there is an issue with that circuit (faulty temp sensor or low voltage to it) the transmission will not shift.

If not that...then I would suspect a shift solenoid.

There is also an O/D Direct Clutch speed sensor that can cause your problem.

 

[Mauser]

Did they power flush it? Flushing usually isnt a good thing. My sister let the oil jockies talk her into a flush on her car at one of the quick lube joints and it trashed the transmission. Flushing can push stuck built up crud into places it shouldn't be.

 

[flintknapper]

Did they power flush it? Flushing usually isnt a good thing. My sister let the oil jockies talk her into a flush on her car at one of the quick lube joints and it trashed the transmission. Flushing can push stuck built up crud into places it shouldn't be.

Rarely do shops do a 'power flush' vs. a 'fluid exchange' anymore...but you are correct. A 'power flush' is an excellent way to stir up the fine 'sludge' in the bottom of the pan and have it go right into the Valve Body.

But it sounds as if the OP had the problem (or the beginnings of it) before the transmission service.

 

[tracknod]

Hey guys,

Yes it was a power flush. Toyota in Portland did it and I specifically talked to the master tech that worked on the truck.

As for temp, yes the atf fluid is up to temp as the scan gauge is reading 145-180. It just won’t go into overdrive at all.

Where exactly is the shift solenoid?

 

[flintknapper]

Yes it was a power flush. Toyota in Portland did it and I specifically talked to the master tech that worked on the truck.

^^^^^^ Groan...........!

 

[suprarx7nut]

I apologize if this is a dumb question, but you don't seem to have clarified. Maybe you did and I missed it.

Were you towing with OD on? Are you still towing? OD should always be off while towing.

 

[flintknapper]

Hey guys,

Yes it was a power flush. Toyota in Portland did it and I specifically talked to the master tech that worked on the truck.

As for temp, yes the atf fluid is up to temp as the scan gauge is reading 145-180. It just won’t go into overdrive at all.

Where exactly is the shift solenoid?

You may have misread or misunderstood my previous post. The 'temp' I was inquiring about is your Coolant Temperature not trans temp. The transmission will not shift into overdrive until your engine coolant temp reaches about 130° F. So if the sensor is faulty in any way (mis-reading, low voltage) it might be a cause.

Its just something to check. A shift solenoid, O/D Direct Clutch speed sensor or the Valve Body itself are other possibilities.

 

[flintknapper]

When you press your overdrive button 'on' to disengage OD...does the light on the dash come on? If so..then we know that portion of the circuit is probably good...but that doesn't mean the switch is working when left in the OD position. About the only way to check that...would be to remove the connector from the switch and check for continuity between the 5 & 10 wires.

 

[Spike555]

Just because your temp gauge reads normal does not mean your ECU is reading the correct coolant temp.
This is why @flintknapper is asking what your scanguage reads for engine temp, that will show you the same temp the ECU see's.

I had a problem with my Land Rover once stalling at stop lights and really bad MPG, turns out the engine temp sensor was bad, temp gauge read fine but because the temp sensor was bad the ECU thought the engine was -40*F so it was running full choke and flooding out the engine when hot. There were two temp sensors. One for the gauge and one for the ECU.

For lower emissions your truck will not shift into overdrive until the engine is warm, a warm engine uses less fuel than a cold one.
So if the transmission computer thinks the engine is not warm it will not shift into overdrive.
This shortens the time it take for the engine to reach operating temp which reduces emissions.

 

[tracknod]

Ok guys... sorry for no reply, but we have just been driving home... at 61 mph since the truck won’t go into overdrive for 4K Miles.

So let me answer a few questions.

Yes, the scan gauge is showing a water temp of 190-210 and the atf is running 150-200+ depending on the passes. (HOLY CRAP Teton Pass is a Muther F’r.)

Yes, the OD button lights the dash light and turns it off when you depress it again.

The truck also would randomly go into overdrive about once every two days or so for about 50 Miles, but suddenly jump back to third gear just as quick as it started. This would happen just randomly when the truck wasn’t accelerating and on completely flat road such as through Kansas.

I did stop and talk to a transmission shop and they said they doubted it was the shift selenoid since I had first gear. The owner basically said the selenoid was on/on or off/off, and since I had the other gears he didn’t think it was that. Does that make sense?


I should say the truck is running great otherwise. 12k Miles and other than this all has been great.. it hasn’t thrown a single CEL


@flintknapper ... you said it may be the OD sensor. Where is that and what is the part number. I can’t seem to find it.

Thanks for everyone’s help. TIA.

 

[Spike555]

Your thermostat is bad.
Replace it.
170 is to cold.
210 is on the high side.
Your engine temp is not being properly regulated.
Replace thermostat. Report back.

 

[tracknod]

Your thermostat is bad.
Replace it.
170 is to cold.
210 is on the high side.
Your engine temp is not being properly regulated.
Replace thermostat. Report back.

sorry.. that was a typo... 170 was 190.

The temp when it got to 210 were on elevation climbs where we were climbing 8-10% grades.

95% of the time the water temp was 191-200.

 

[flintknapper]

@flintknapper ... you said it may be the OD sensor. Where is that and what is the part number.
.

Your OD direct clutch sensor is on the transmission (drivers side) forward part of transmission right behind the bell housing portion.

You should check the wiring to it and the connection itself. If all that looks good...then remove the sensor and check the resistance (should be between 560-680 ohms @ 70° F).

 

[Volunteer2005LC]

In to see where this goes