Changing lo to hi range in 150

[vk2ss55 Senior Member Find all posts View Profile Close vk2ss55]

I've noticed at times when changing from lo to hi range that the orange light flashes and the beeper sounds and it stays in lo range .
I have to switch back to lo and jiggle back and forth and finally it'll go into hi range and the beeper will stop .
Anybody had this problem ?
Cheers
Ross

[mrkrinkle Senior Member Find all posts View Profile Close mrkrinkle]

I have similar problems with my 95 series sometimes.

Just chuck it in reverse and drive back a little and the then it should go back to high no worries....

[williade Avid PP Poster! Find all posts View Profile Close williade]

Mrkrinkle: your problem is the centre diff lock not disengaging, I'm guessing? That sounds like transmission wind up and you are correct in how to disengage it.

Vk2ss55: is your prado a manual or auto? If manual is the clutch disengaged and if auto is the transmission if neutral when you turn the dial? The CDL sticking due to windup is one thing but the t-case should be able change between high and low range easily. I'd be curious to see some replies from other 150 owners.

[andoland Senior Member Find all posts View Profile Close andoland]

To succesfully change between high and low range you have to have the vehicle in neutral and the clutch pushed all the way in (same as starting), then turn the knob, then wait until high/low range is engaged and only after that can you move the gear lever or let the clutch pedal out. If you don't wait (e.g. turn the dial then whack it into gear straight away or let the clutch pedal out a touch) it will not disengage low range. This is really frustrating but that's how it is.

[williade Avid PP Poster! Find all posts View Profile Close williade]

That's what I love about a stick shift transfer case. You don't have to deal with actuator motors and their mood swings.

[vk2ss55 Senior Member Find all posts View Profile Close vk2ss55]

Williade
My 150 is an auto and yes it's in neutral when turning the knob . I used to have a 120 and yes you had to maybe go forward and backward for it to disengage lo range and the orange light to go off, but it did disengage . The 150 seems to take a bit more rocking for it to disengage , with the orange light flashing and the beeper sounding . Maybe it's just wind up as you say .
Cheers
Ross

[footoo Member Find all posts View Profile Close footoo]

Mine is what you might call a brand spanker (2 weeks old) and it goes in and out of low with no problems, apart from the clunk which is a bit daunting. Your gear box/transfer case might just be a bit tight which translates to you need to get out there and use it a bit more, as we all love to do..

[williade Avid PP Poster! Find all posts View Profile Close williade]

Ross, I think you may be confusing the centre-diff lock not disengaging, which may require you to roll backward or forward to release the drive line windup, with changing from low range gearing to high range. The light you can see on the dash is telling you the CDL is engaged. Maybe another 150 owner can confirm this.

I have had the CDL being very stubborn before (had to reverse backwards at speed and flick the transmission into neutral to get the CDL to disengage) but I have never had the T-case refuse to come out of low range. In theory, any torsion/binding/windup in the gear teeth would be released when the t-case is placed in neutral (ie when shifting from L->N->H) almost like jacking up a wheel to release drive line windup for a stubborn CDL.

[vk2ss55 Senior Member Find all posts View Profile Close vk2ss55]

Williade

I think you hit it right on the head mate.....I need to get out and do more low range stuff !
Cheers
Ross

[barajak Senior Member Find all posts View Profile Close barajak]

This could be wind up. I use the CDL when required and then disengage it until it is neaded again. The vehicle is quieter and the stearing more positive with the CDL disengaged as is has no wind up then when you stop to engage high range, it changes without hesitation every time. The CDL can be engaged and disengaged on the move so turn it off before you stop for the range change.

[williade Avid PP Poster! Find all posts View Profile Close williade]

Wind up from the CDL will put torsional stress on the cv's, axles, diffs, prop shafts, uni joints and the output shafts of the transfer case. The wind up ends there. The hi-lo range planetery gearset is unaffected any other drive line torsional stresses if you place the transmission in neutral like you are supposed to.

[barajak Senior Member Find all posts View Profile Close barajak]

Hi Williade, Correct me if i'm wrong, i'm not a mechanic but the transmission is between the transfer case and the engine so shifting to neutral will unload the pressure to the transfer case from the engine. It will do nothing to ease the pressure of one of the gearsets involved in the gear shift. Any mechanical gear shift will go easier without torsional stress involved.

[williade Avid PP Poster! Find all posts View Profile Close williade]

Hi barajak. The transfer case in a full-time 4wd had two main components. The low range reduction planetary gear set and the centre differential, also a planetary gear set. When the centre diff lock is stuck, the sun and planet gears of the diff are under load because of torsion from the front and rear prop shafts. The input for the centre diff (ie the output from the hi-lo gear set) is un affected by this. The hi-lo gear set is only placed under load when it receives drive from the transmission. So placing the transmission in neutral (having the clutch in for a manual) will release any torsion being applied to the hi-lo gear set.