1st gear only "4 LOW"

Hey was driving home from work tonight and decided to stop in the middle of the road and drive on 4 high just to make sure everthing stays lubricated. Stopped about a couple miles short from home and kicked it into 4 Low, This is the question? The trans never shifted out of 1st gear in 4 Low? Is this normal? RPM shot all the way up 5500+ before i decided to back it off.

 

Was the gear selector in D ?

 

Yes....

 

Intetesting

What kind of speed were you at with the rpms at 5500 ?

 

40ish... is this normal???

 

I didn't think 40mph was possible in 4low/1st gear.

 

I dont think so either. I do remember in my 89 toyota p/u I had it in 4lo and 5th gear and was only doing like 35. RPMs are going to climb crazy fast in 4lo. Are you sure it wasnt shifting and you just didn't notice?

 

That is possible in D

Maybe you didn't notice it shifting up

 

It's not. He doesn't know what 4LO is.

A750F Transmission 1st gear ratio is 3.52. 4Lo is a 2.57 ratio. Final drive is 3.73. This is assuming everything is stock. Final
crank to wheel ratio is ~33.7 in 4Lo/1st. At 5500 engine RPM, wheel RPM is ~167. Actual speed will be dependent upon tire circumference, but assuming stock tires at ~96in circumference, that boils down to about 16032in per minute. That's roughly 15mph if you do the math.


Edit: This is assuming the torque converter isn't providing additional reduction, which it shouldn't be once he attains constant speed.

 

You do realize that 4lo is a super low gear reduction, right?

At any given road speed in any given trans gear, the engine rpms will be about 2.5 times higher than in 2hi or 4hi.

2hi for pavement, 4hi for loose surfaces, 4lo for s-l-o-w-l-y climbing rocks and such

 

Just bought this truck a few weeks and its first time i played the 4lo, But i have driven my friends 08 and in 4lo it shifts like in 2w-4hi? The a-trac and traction light stays on my truck also. I was driving down hill as i watched my rpm reach the limits into red and the truck never shifted out of first gear. Maybe normal? i am going to call toyota coporate to find out.

 

DAC on ?

 

Maybe do it again and video your dash so we can see whats going on...

 

Guys, there's nothing to diagnose here. If he's doing 40mph in 4lo, his truck is shifting through the full range of gears. He's just missing it.

 

.... Yes it's normal. You aren't in first gear. It shifts fast.

Top speed in 4L is ~53MPH (gear limited).