‘99 Highway RPM range (5 Viewers)

[900exdriver]

Quick update. I pulled data with a obd scanner. No codes. Engine coolant temp rises normally cruising along and maintains an average 175-180 f. So I think can check off the engine temp sensor. Reading similar posts/threads, mostly 80’s series, bad solenoids are sometimes the cause of transmisson issues. I might look into a new solenoids along with a new filter.

 

[MongooseGA]

If you're still looking in the next few days... I might have a solenoid for you if they're reusable parts.

This may be off, but my old Benz uses a series of adjustment cables to regulate shifting and whatnot. Turn one cable too far, it won't shift into high gear. Don't turn it enough and it may just stack shifts to get into top gear right away. I wonder if there's any possibility our trucks have some sort of adjustment feature as well? I'm sure not the same mechanical system but maybe in techstream?

 

[900exdriver]

Update time: pulled the pan. Changed out solenoid #2 and replaced the filter. Still stuck in 3rd at highway speeds. #2 controls 3rd-4th. Back to the drawing board.

Is there a ecu for the tranny?

 

[2001LC]

Quick update. I pulled data with a obd scanner. No codes. Engine coolant temp rises normally cruising along and maintains an average 175-180 f. So I think can check off the engine temp sensor. Reading similar posts/threads, mostly 80’s series, bad solenoids are sometimes the cause of transmisson issues. I might look into a new solenoids along with a new filter.

That seems just a little low. If that's while running 70MPH at ~3K plus RPM for 5 minutes, I'd look for 187 to 192 F possible 197f. I wouldn't think low enough to prevent shift up, but!

 

[STIGPIG]

Wow
Definitely stuck in 3rd
My 99 has 5.29s and 3k RPM is over 80mph

 

[900exdriver]

That seems just a little low. If that's while running 70MPH at ~3K plus RPM for 5 minutes, I'd look for 187 to 192 F possible 197f. I wouldn't think low enough to prevent shift up, but!

I went back out today. Fluid is full in the hot range. Temp got up to 192. I think I read that the temp needs to get to 125 before shifting to 4th. So I think I’m covered there.

Not sure if this is normal but I’ll be at highway speed and if I let the pedal go idle RPM’s drop to 800-1000. I thought the RPM’s should relatively be in 2k-3k until once slowed down.

 

[pjess50]

Maybe I'm missing something but isn't stock tie size 275/ 70/16? Using a smaller tire size would lead to higher rpms.

 

[CorporalClegg]

definitely a transmission control module, you need tis. Do you have access to a high end scanner?


pjess50, yes tire sizes affect gear ratio and "true" speed, but the odometer will read the same.

 

[Ohiolc100]

I have 265/70/16s on mine 2450rpm at 70mph

 

[900exdriver]

Maybe I'm missing something but isn't stock tie size 275/ 70/16? Using a smaller tire size would lead to higher rpms.

I’m running 33’s.

definitely a transmission control module, you need tis. Do you have access to a high end scanner?

I’ll look into the module. I have a Bluetooth scanner and it’s pulling up no codes. I think it’s time for me to get techstream.

 

[900exdriver]

Land cruiser-3
Me- 0

The saga continues...

I’ve read about the a343f as much as my eyeballs can handle. I’ve referenced many post (this for example Stelah Won’t Shift Into Overdrive/Forth Gear (urgent)) about shifting issues and learned a lot. But I’m still at lost as to why I can’t get this thing to shift into 4th/OD.

So far I have replaced the fluid twice. Changed out the #2 solenoid, filter, ECT sensor, and the OD direct clutch speed sensor. Those items seem to be the hot ticket to the lack of higher gears. I even pull the ecu to see if I had any burnt or destroyed capticators.

Also seemed a common issue with the Surf that ran a a343f.

Am I missing anything else? Any ideas, criticism, smartass remarks!? My next purchase will be a cable for techstream.

 

[89BIGBLUE]

Is there a way to test the OD button or wiring?
The truck seems to be telling you it’s healthy...no codes or misbehavior...like it’s doing what it’s being told to do.
Just thinking at it...

 

[900exdriver]

Is there a way to test the OD button or wiring?
The truck seems to be telling you it’s healthy...no codes or misbehavior...like it’s doing what it’s being told to do.
Just thinking at it...

Well, referencing the other thread @flintknapper suggested this

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.

I suppose I can pull the switch and check. I do get the OD light on the dash.

 

[900exdriver]

I pulled the center shift console. Checked the O/D main switch and shift lock control ecu. It looked pretty toasty. What do you all think?

Connected the the volt meter to pin 5 and 10 and this what I got.

 

[KillerBox]

I pulled the center shift console. Checked the O/D main switch and shift lock control ecu. It looked pretty toasty. What do you all think?
View attachment 1833047

Connected the the volt meter to pin 5 and 10 and this what I got.

View attachment 1833048

900exdriver did you fix your overdrive problem?

 

[BillysIdol]

Next time I am on the highway, I will have to see where my RPMs are at 70MPH. I took a big road trip and I felt like I was also having an issue with the truck getting into 4th. I played with the O/D off button and noticed a rise in RPMs. That being said, I was getting about 17 MPG on the highway so maybe it was going into 4th after all...

 

[900exdriver]

900exdriver did you fix your overdrive problem?

I haven’t. I ordered a new O/D main switch. Still haven’t received it. While I’m waiting I’m trying to figure out if it’s normal for the rpms to drop to idle at cruise speeds when I let off the gas. I’ll let off at 60 mph and my rpms drop from 3000 to 1000 or so. Not sure that’s norm. I thought the rpms should at least hang for a bit at those speeds.

When I the switch arrives I’ll be sure post an update.

 

[MongooseGA]

I haven’t. I ordered a new O/D main switch. Still haven’t received it. While I’m waiting I’m trying to figure out if it’s normal for the rpms to drop to idle at cruise speeds when I let off the gas. I’ll let off at 60 mph and my rpms drop from 3000 to 1000 or so. Not sure that’s norm. I thought the rpms should at least hang for a bit at those speeds.

When I the switch arrives I’ll be sure post an update.

I remember you asking about this before and I made a mental note one of the last times I was driving mine. Not exactly apples to apples with mine being the 5 speed, but I do remember that my engine speed fell, but still nowhere near down to 1000 RPM.

 

[KillerBox]

I haven’t. I ordered a new O/D main switch. Still haven’t received it. While I’m waiting I’m trying to figure out if it’s normal for the rpms to drop to idle at cruise speeds when I let off the gas. I’ll let off at 60 mph and my rpms drop from 3000 to 1000 or so. Not sure that’s norm. I thought the rpms should at least hang for a bit at those speeds.

When I the switch arrives I’ll be sure post an update.

IDK, 990exdriver. I had an intermediate type of stalling problem with my 2001 LX. It only happened (sometimes) after I applied throttle from an idle. That idle could be leaving a redlight or coasting down a hill. So it could very well be going back to idle very quickly.

Btw on my 4 speed transmission, I am doing 2,600 rpm at 75 mph.

 

[900exdriver]

Well, another update. The switch didn’t help. Back to the drawing board again. TechStream just came in so I’ll dig into that soon. Looking at the repair manual matrix charts. A few more items to check and then I’m out of ideas. Might seek a professional help.