4WD Manuel Transmission Queston
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captwalker87
New member
i didnt have a owners manual either, and i thought i would try on-the-fly shifting. well, bad idea. it shifted into 4hi, with an awesome BANG and nice clicking noises. turns out, i ruined my front diff and its ADD system, even though i was only moving 10 mph. so i replaced the front diff, it wouldve been nice to find out it doesnt do on the fly another way.
http://www.showmesome.info/hilux/info/faq.htm#4x4damage
I copied & pasted the info:
"Question: Why can't I use 4x4 mode all the time or on the roads?
Answer: There's drive to both axles and the front and rear axles have different turning circles. On hard/dry surfaces like tarmac there's no give on the road surface so you'll end up with windup on the transmission which can destroy it.
Permanent 4WD vehicles like Range Rovers have a differential in the transfer case to allow it to slip as you turn in circles. The Surf is not intended as a permanent 4WD vehicle.
Misc."
Sidney
I copied & pasted the info:
"Question: Why can't I use 4x4 mode all the time or on the roads?
Answer: There's drive to both axles and the front and rear axles have different turning circles. On hard/dry surfaces like tarmac there's no give on the road surface so you'll end up with windup on the transmission which can destroy it.
Permanent 4WD vehicles like Range Rovers have a differential in the transfer case to allow it to slip as you turn in circles. The Surf is not intended as a permanent 4WD vehicle.
Misc."
Sidney
Bilzo
New member
I have a '95 SR5 V6 4WD and the manual says that shifting from H2 to H4 can be done at any speed up to 50mph, and shifting from H4 to H2 can be done at any speed. Shifting from H4 to L4 needs to be done at speeds less than 5mph, and the clutch must be depressed. Shifting from L4 to H4 can be done at any speed with the clutch depressed.
Personally, I've never tried doing any of this. I'll always engage the front drive when I'm stopped.
Personally, I've never tried doing any of this. I'll always engage the front drive when I'm stopped.
regularguy412
New member
For what it's worth, I have a 92 V-6 3.0 with an auto tranny and integral transfer case. That means, the transfer case shares and uses the same ATF that the A340H auto tranny uses, for its own lubrication. The tranny and transfer case cannot be separated.
I have both engaged and disengaged the ADD front axle on numerous occasions -- going from 2H to 4H on the fly and back to 2H. I agree with Bilzo about not shifing into 4H at an unreasonably fast speed -- especially if you are on a slippery surface. I have noted no unusual or scary noises coming from the front end or tranny/transfer areas when performing these actions. I 'can' hear the hubs engage when doing this ,, and I can also hear the hubs / axles disengage and eventually stop turning while still moving forward, at speed.
I noted when reading my owner's manual, that Toyota recommends the front axle be engaged for a distance of approximately 10 miles at least once per month. I don't always get that accomplished, but it seems front hubs and axles need to have the internal lubrication moved around on a regular basis.
There are currently 182,000 miles on my 4runner.
Mike in AR
I have both engaged and disengaged the ADD front axle on numerous occasions -- going from 2H to 4H on the fly and back to 2H. I agree with Bilzo about not shifing into 4H at an unreasonably fast speed -- especially if you are on a slippery surface. I have noted no unusual or scary noises coming from the front end or tranny/transfer areas when performing these actions. I 'can' hear the hubs engage when doing this ,, and I can also hear the hubs / axles disengage and eventually stop turning while still moving forward, at speed.
I noted when reading my owner's manual, that Toyota recommends the front axle be engaged for a distance of approximately 10 miles at least once per month. I don't always get that accomplished, but it seems front hubs and axles need to have the internal lubrication moved around on a regular basis.
There are currently 182,000 miles on my 4runner.
Mike in AR
