Difficulty engaging 4 lo? (1 Viewer)

[re_guderian]

Ugh, I hate electronics for things that are better suited to a lever.... This weekend when I was stopped (admittedly too late, as I was on some off-camber, mogul dirt sections) to engage 4 low, I got the dash light flashing and beeping, and it would not engage into low range. I was in N, and then tried inching forward or back. If I left it in low, and hit the gas, I gat a grinding/whirring noise. Never had this happen before. No codes, and after 3-4 tries, it finally went into low range. Not sure if it was lack of use (ugh, I suck, been a few months since engaging low range) or the terrain, angles, and how I had the driveline wound up at the time that caused this. Anyone else had similar happen to them?

 

[r2m]

Ugh, I hate electronics for things that are better suited to a lever.... This weekend when I was stopped (admittedly too late, as I was on some off-camber, mogul dirt sections) to engage 4 low, I got the dash light flashing and beeping, and it would not engage into low range. I was in N, and then tried inching forward or back. If I left it in low, and hit the gas, I gat a grinding/whirring noise. Never had this happen before. No codes, and after 3-4 tries, it finally went into low range. Not sure if it was lack of use (ugh, I suck, been a few months since engaging low range) or the terrain, angles, and how I had the driveline wound up at the time that caused this. Anyone else had similar happen to them?

Yes, I had this happen also, but I was trying to disengage 4LO. I too was at a weird angle and incline and got the same noise but wouldn't disengage.
It wasn't until I was completely level again everything worked fine. At first I though I really jacked something up and have to be towed home, but all was fine.
It seems that our rigs like to be sitting level and not under any strain when shifting into/out of 4LO.
Short story is, I wouldn't worry about it. This happened to me several years ago and never since but I do shift in and out of 4LO when flat and not under load.

 

[Acrad]

Unfortunately for 10-19 models you have to use a multimeter for troubleshooting. Only '20+ can you pull codes for this area of the vehicle.

Torsen Diff (VF4BM) - Technical overview / Diagnostics / Troubleshooting - ClubLexus - Lexus Forum Discussion

GX - 2nd Gen (2010-2023) - Torsen Diff (VF4BM) - Technical overview / Diagnostics / Troubleshooting - NOTE: Multimeter testing required for this area for 2010-2019 models The FSM would be best but here is a document on troubleshooting various Toyota 4WD/AWD systems. The center diff/transfer case...

www.clublexus.com

 

[Rednexus]

Even with a lever it can still be difficult when the drivetrain is stressed due to the trans being in park on a incline. Prior to the 4-low shift, I recommend coming to a complete stop, putting the rig in neutral, letting it move a few inches/feet in neutral, putting your foot on the brake (and keeping it there), putting the rig in park (foot still on brake), then doing the 4-low shift (foot still on brake, remove when the shift is done). This will take all stress off of the drivetrain and allow it to shift much easier.

If you are on anything but totally flat ground there can be a lot of stress on the drivetrain without taking these steps and it may make a shift difficult.

I also don't know about the 460 but if I try a lever shift into 4-low with the trans in N I'll get grinding noises, 100% of the time. It needs to go from N and then into P to avoid this, prior to a shift. If you tried it in N only you'll get grinding.