2Hi to 4Lo, bug or feature?

This is my 6th 4x4 vehicle. Half had a floor shifter, sold that last one last week and I already miss the floor shifter.

Of the 3 with knobs, this is my first that I can't go straight from 2Hi to 4Lo even in Neutral with feet on clutch and brake. Well, the knob will go, but the indicators only flash. If I shift to 4Hi, and wait for the indicator to stop flashing, which usually requires also putting it in gear and move a few inches, then going to 4Lo works.

'07 GMC Sierra could go straight from 2Hi to 4Lo
'12 Nissan Xterra could go straight from 2Hi to 4Lo

Mentioned this to my friend, he previously owned F-150, Titan and Ram, all 3 would do it too.

Is this a bug or a feature?

 

I wouldn’t call it a bug or a feature, just a characteristic of the Tacoma’s system.

 

It’s because the 2WD to 4H shift is not complete until the ADD is locked in. Only then will it allow 4H to 4L. So because you are sitting still and the ADD isn’t lined up, it won’t go until you move. So in theory you could shift across both modes, but the ADD would have to be in the perfect spot while you’re sitting, which is very unlikely.

A lever to yank on is much preferred in my opinion. I don’t like the knob or ADD, but I got rid of the ADD and so now it at least shifts quickly electronically. Since I spoofed the ADD electronically, it will shift both times in one go.

Technically, you could delete the ADD on a 2024 as well using parts from the full time 4WD Limited model. But the wiring connectors are not really easy to locate to build a harness for spoofing.

 

Not familiar with all the Toyota acronyms yet, what's ADD?

 

Automatic disconnecting differential. It’s a coupler in the right side front diff tube that disconnects the right side axle shaft. This lets only the spider gears spin (driven by the left axle), instead of the front driveshaft and ring & pinion. Some see it as a benefit, I don’t really. It’s mostly done for CAFE/mpg related stuff.

It’s not a terrible thing, it works okay but when it doesn’t work, it becomes a headache to deal with. Most problems are due to moisture, if moisture is kept out of the ADD actuator motor, it will probably live a good long time. Still makes shifts take an annoyingly long time to complete sometimes.

 

And manual locking hubs.

 

I can get the merit to hubs, but don’t want them for myself. I’d leave them locked all the time except maybe a roadtrip if I had them.

I want things continuously moving so nothing ever seizes. Seals sticking, etc.

 

Only had them on my '88 Ford Ranger. I'd leave them locked all winter. In the summer, I'd lock them when leaving home if I had plans to leave pavement.

 

The chief engineer Sheldon Brown specifically says in the tacoma you need to go 2Hi, 4Hi, 4Lo and should also do that in reverse when coming out of 4Lo. It's just the way Toyota designs it. Also, Tacoma's are notorious for being tricky to get in and out of 4Lo. Always irritated me.

 

Since you can shift to 4Hi while on the move I don't see the need to stop and go straight to 4Lo from 2Hi. Just shift it to 4Hi before stopping then when stopped you are ready to go into 4Lo.

 

I respect Sheldon brown and what he’s helped to push with the truck, but a decent amount of what he has said isn’t technically accurate when you dig into the details. The transfer case naturally shifts 2H-4H-4L, but there is no reason for it to not do both shifts in a row with one turn of the knob…the exception is it is waiting on the ADD before going to low. If the ADD is out of the equation, then it will make both shifts in a row no problem. It is nothing specific to the design of anything, it’s just the way it is because the ADD is there and not pre lined up 99% of the time.

 

That would work when I'm already on the move, but that's not always the case. I use 4-Low often on my property because of steep hills, wimpy clutch and a reverse gear ratio for racing.

 

It's annoying- waiting for Toyotas to do their Toyota crap. It's been a Toyota thing for a long time.

 

Last had manual locking hubs and transfer case on my 1987 Bronco. I would always lock the hubs ahead of time before leaving the house if I was expecting any chance of snow and might need to shift on the fly to 4H.

Some of my co-workers had late 80's Chevy's and Ford's with electronically controlled 4WD and they were always acting up.

 

I don't disagree with your point, however, it seems to works best (quick engagement wise) when going in order. That was always the case in my 2nd gen and seems to follow suit on my now ex's 3rd gen and now the 4th. Waiting for 4hi to lock in before going to 4lo just seems to lead to a quicker completed shift into 4lo.