4 HI won't shift on the fly

[Soneill]

4 HI won't shift on the fly

1st off: 2011 SR5, 128k, lever shift 4x4

Yesterday morning it was raining and I went to shift into 4 HI while I was driving. The 4x4 light just kept flashing. At one point it seemed like 4 wheel drive had engaged but not completely. I pulled over and stopped it - finally got it to engaged after some fiddling. I tested 4 Low, no problems. Put it back in 4 HI and hit the road. Got up to 60 and had crazy vibration coming from the front drive train. Went to put it back in 2 HI, light just flashed(like before) and 4 HI was still engaged. I drove about a mile and it still wouldn't disengage. I made a right turn to find a place to stop and heard and felt a loud "BANG", truck went back into 2HI.

After more testing of the 4HI transition. I found the truck will only shift into 4HI while sitting still and 4 HI will ONLY disengage when put into REVERSE. I tried driving forward and turning the wheel left and right, no difference. I did find a torn CV boot on the passenger side, that may be the vibration but I'm not too sure. Has anyone run into anything like this? Before yesterday it would shift IN and OUT of 4 HI while driving forward, backward or sitting still without an issue.

 

[fixer5000]

all 4 tires have about the same amount of wear? diameter same?

 

[Thebeastlives]

4 HI won't shift on the fly

1st off: 2011 SR5, 128k, lever shift 4x4

Yesterday morning it was raining and I went to shift into 4 HI while I was driving. The 4x4 light just kept flashing. At one point it seemed like 4 wheel drive had engaged but not completely. I pulled over and stopped it - finally got it to engaged after some fiddling. I tested 4 Low, no problems. Put it back in 4 HI and hit the road. Got up to 60 and had crazy vibration coming from the front drive train. Went to put it back in 2 HI, light just flashed(like before) and 4 HI was still engaged. I drove about a mile and it still wouldn't disengage. I made a right turn to find a place to stop and heard and felt a loud "BANG", truck went back into 2HI.

After more testing of the 4HI transition. I found the truck will only shift into 4HI while sitting still and 4 HI will ONLY disengage when put into REVERSE. I tried driving forward and turning the wheel left and right, no difference. I did find a torn CV boot on the passenger side, that may be the vibration but I'm not too sure. Has anyone run into anything like this? Before yesterday it would shift IN and OUT of 4 HI while driving forward, backward or sitting still without an issue.

I have a 2008 Tundra, 08, 96, 2019 Trd 4runner and I put them all in 4 wd hi stopped and neutral and get them out of 4 hi by reversing a little. Taught all the sons to do the same over the years and 4 wd has never not worked

 

[Salvo Jimmy]

4 HI won't shift on the fly

1st off: 2011 SR5, 128k, lever shift 4x4

Yesterday morning it was raining and I went to shift into 4 HI while I was driving. The 4x4 light just kept flashing. At one point it seemed like 4 wheel drive had engaged but not completely. I pulled over and stopped it - finally got it to engaged after some fiddling. I tested 4 Low, no problems. Put it back in 4 HI and hit the road. Got up to 60 and had crazy vibration coming from the front drive train. Went to put it back in 2 HI, light just flashed(like before) and 4 HI was still engaged. I drove about a mile and it still wouldn't disengage. I made a right turn to find a place to stop and heard and felt a loud "BANG", truck went back into 2HI.

After more testing of the 4HI transition. I found the truck will only shift into 4HI while sitting still and 4 HI will ONLY disengage when put into REVERSE. I tried driving forward and turning the wheel left and right, no difference. I did find a torn CV boot on the passenger side, that may be the vibration but I'm not too sure. Has anyone run into anything like this? Before yesterday it would shift IN and OUT of 4 HI while driving forward, backward or sitting still without an issue.

Do you exercise it in 4WD regularly?

 

[rightyouareken]

When was the last time your diff/tcase fluids were changed? If it's been a while, it might be a good idea to change them. On my 3rd gen I noticed 4hi engage quite a bit quicker after I changed the fluids. Sometimes fresh fluid loosens things back up a bit. Also like previously mentioned, exercising it regularly also helps the solenoids remain free and keeps them from getting sticky.

 

[Ogre75]

You shift to 4Hi at 60mph? Not for nothin, but if you need 4hi maybe 60mph is a bit too swift. This isn't an AWD system, can't imagine repeated use of 4Hi at that speed, even on wet pavement is good for it. Just my $.02

 

[Whippersnapper02]

4wd high should be selected on the fly under like 50mph or whatever the manual states. Also let off the throttle when shifting to make it easier on the system. As mentioned, 4wd is not AWD so you really don't need it in the rain.

 

[Ronin_Runner]

following.

Was also told don't need it in the rain

 

[jhguth]

putting it in 4hi in the rain will reduce your traction, not improve it

as you turn all 4 wheels follow different arcs, not just side to side but also front to back. except for on the limited, the 4wd system just has a center transfer case which means there is nothing acting as a differential between the front and rear axle

the safest, best traction for wet pavement is to leave all diffs open and let traction and stability control do their jobs if needed

 

[mscot]

putting it in 4hi in the rain will reduce your traction, not improve it

as you turn all 4 wheels follow different arcs, not just side to side but also front to back. except for on the limited, the 4wd system just has a center transfer case which means there is nothing acting as a differential between the front and rear axle

the safest, best traction for wet pavement is to leave all diffs open and let traction and stability control do their jobs if needed

Interesting. How about in snow?

 

[jhguth]

the same thing about tires following different paths in snow is still true, but in snow the traction can be so limited you sometimes will need both axles driving and it doesn't matter that the tradeoff is that this technically means at least 1 tire is scrubbing in turns because the traction is limited enough that it would slide or scrub anyways.

also i'm not saying it would generally make a significant difference on wet pavement, just that whatever change would be negative not positive. and as others have mentioned it's just not necessary

 

[Soneill]

all 4 tires have about the same amount of wear? diameter same?

Yes, all the same. Brand new as well

 

[Soneill]

putting it in 4hi in the rain will reduce your traction, not improve it

as you turn all 4 wheels follow different arcs, not just side to side but also front to back. except for on the limited, the 4wd system just has a center transfer case which means there is nothing acting as a differential between the front and rear axle

the safest, best traction for wet pavement is to leave all diffs open and let traction and stability control do their jobs if needed

Thanks for the info. I still don't know why I have to be stationary for it to shift into 4HI. Never had a problem before especially off road.

 

[Soneill]

4wd high should be selected on the fly under like 50mph or whatever the manual states. Also let off the throttle when shifting to make it easier on the system. As mentioned, 4wd is not AWD so you really don't need it in the rain.

I can't even get it to engage at 10 mph on the drit road by my work. If I'm in motion at any speed, it will not engage.

 

[Soneill]

You shift to 4Hi at 60mph? Not for nothin, but if you need 4hi maybe 60mph is a bit too swift. This isn't an AWD system, can't imagine repeated use of 4Hi at that speed, even on wet pavement is good for it. Just my $.02

No, shifted below 50 mph. Then got up to 60 and its never repetitive. She is off road in 4 wheel more often. The main issue is that all of the sudden I have to be stopped for 4HI to engage. Then it will only disengage in reverse.

 

[Soneill]

When was the last time your diff/tcase fluids were changed? If it's been a while, it might be a good idea to change them. On my 3rd gen I noticed 4hi engage quite a bit quicker after I changed the fluids. Sometimes fresh fluid loosens things back up a bit. Also like previously mentioned, exercising it regularly also helps the solenoids remain free and keeps them from getting sticky.

It is time for a fluid change. I'll do it this weekend and see if it helps. But yes it get regular exercise

 

[Soneill]

I have a 2008 Tundra, 08, 96, 2019 Trd 4runner and I put them all in 4 wd hi stopped and neutral and get them out of 4 hi by reversing a little. Taught all the sons to do the same over the years and 4 wd has never not worked

Thats good practice but I have never had in issue before the other day. Manual evens says you can be in motion under 50 mph

 

[Whippersnapper02]

I can't even get it to engage at 10 mph on the drit road by my work. If I'm in motion at any speed, it will not engage.

Have you ever changed the fluid? I'd look into it. I'm assuming electronic shifter? Maybe the actuator motor is getting weak.

 

[Soneill]

Have you ever changed the fluid? I'd look into it. I'm assuming electronic shifter? Maybe the actuator motor is getting weak.

Its ready to be changed, going to do it the weekend. It has a shift lever. I was worried about it being the ADD actuator. I wonder if there is an way to test it.

 

[Pbuscemi]

Tire Size

My 4Runner (05 V6 4WD) is currently not shifting on the fly either. I hear a loud clicking or clunking (Not grinding) when I try to disengage.

My tires haven't all come in yet, so the rear ones are 265/75 and the front are 265/65. Would that cause the issue?

all 4 tires have about the same amount of wear? diameter same?