Failing the 4H Test?

[MHG]

Got me 2025 Taco home. Live on Long Island so off-roading places are limited. Beaches open on April 1. Testing putting it into 4L and 4H Saturday. Did. It seem to disengage from 4H (although the 4H icon went out). Drove and heard a loud clunk on a the . Backed up and went forward all seams good.

Wanted to test my 4WD so went to a parking lot. Put the front wheels against the curb. Stepped on gas and felt a tone of resistance. Engage 4H and it feels the same. Engage 4L and it goes right up the curb effortlessly.

Guess my question is, is it possible for 4L to work and 4H to display its working but not actually engage? I would think it’s the same inside the front did, just a lower gear on the trans.

Again, all indications on the dash tell me it’s engaging. I may have had the traction control on so maybe that’s effecting the 4H.

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[BAQ717]

Got me 2025 Taco home. Live on Long Island so off-roading places are limited. Beaches open on April 1. Testing putting it into 4L and 4H Saturday. Did. It seem to disengage from 4H (although the 4H icon went out). Drove and heard a loud clunk on a the . Backed up and went forward all seams good.

Wanted to test my 4WD so went to a parking lot. Put the front wheels against the curb. Stepped on gas and felt a tone of resistance. Engage 4H and it feels the same. Engage 4L and it goes right up the curb effortlessly.

Guess my question is, is it possible for 4L to work and 4H to display its working but not actually engage? I would think it’s the same inside the front did, just a lower gear on the trans.

Again, all indications on the dash tell me it’s engaging. I may have had the traction control on so maybe that’s effecting the 4H.

You’re overthinking it, my fellow Taco enthusiast. I’m sure it’s just fine, I believe it’s just a matter of gearing. Wait till those beaches open up and enjoy. Can’t wait to get mine on the sand sometime this summer.

 

[StreeTaco]

4H engages whilst moving.

 

[GMak621]

4H engages whilst moving.

X2

4HI engages easier while you’re moving. I usually do it around 25mph with foot off the throttle, coasting

 

[MHG]

Well I guess I can add some movement to the test. Although you would think the ADD is still engaging and disengaging the same differential .

 

[Forest Moon]

You don't have to jump a curb to test the 4wd. Just drive around in a circle. Then on a straightaway, engage 4H and circle around again. There should be a lot of resistance when turning on pavement. You can do this at very slow speeds.

 

[gasgasman]

Transfer case has to be turning, for the 4x4 to engage.

 

[MHG]

You don't have to jump a curb to test the 4wd. Just drive around in a circle. Then on a straightaway, engage 4H and circle around again. There should be a lot of resistance when turning on pavement. You can do this at very slow speeds.

That’s what I was doing g when I heard the gun shot pop. Trying to avoid doing that again.

 

[Yotota]

The pop was probably the transfer case engaging or disengaging.

How I test modern 4 wheel drive trucks:

- Find a gravel parking lot.
- Drive in a circle in 2wd. Remember how it feels in that gravel.
- Switch to 4High. Wait for the light to stop blinking. If it takes more then 5sec, slowly roll forward in a slight turn until it engages.
- Once engaged, drive in a circle again. You'll feel the front end scrubbing against the gravel.
- Stop. Straighten the wheels, roll forward a little to unbind the drivetrain.
- Trans to neutral, switch to 4Low. Wait for the light to go solid again.
- Trans to drive, do another circle. Should feel like it did in 4High, but a lot slower and torquier.
- Stop. Straighten the wheels, roll forward a little to unbind the drivetrain.
- Have a locker? Time to test it. Push the locker button. Wait for the light to go solid. If it takes more than 5sec, slowly roll forward in a slight turn to get the rear wheels to spin at different speeds and align the diff splines.
- Drive in a circle. Your inner rear wheel should be spinning/hopping a bit on the gravel, and/or the outside rear wheel will be dragging a bit.
- Stop. Push the locker button. Wait 5sec for it to unlock.
- Roll forward slowly and slightly turn left/right to unbind the locker and allow it to pop loose.
- Stop. Straighten the wheels, roll forward a little to unbind the drivetrain.
- Trans to neutral, switch to 2High. Wait for the 4wd light to go out. You'll hear a clunk at the very least.
- Trans to drive. Roll forward slowly to make sure everything is disengaged. It may need a slight turn to let the transfer case disengage.
- The truck should be back to normal in 2wd high.

 

[MHG]

It probably was. It was so loude 3 of my neighbors came running out of their houses to see what hit.

Thanks for taking the time to type all that out. Gravel parking lots are about as common on Long Island as Politicians.

Ill Hit up Google earth to see if I can find one.

 

[MHG]

Well moving and throwing it into 4h did not help. Still takes considerable throttle to mount a curb. In 4L it scoots right up with no effort. Guessing the 4H is messed up. April 1 the beach permits open up here on the island so that will be a true test.

 

[gasgasman]

You do realize that the throttle response changes when in different four wheel drive modes?

 

[Airborne]

Well, i understand the excitement of having a 4x4 , the curiosity will have you looking for snow, mud and any excuse to put it in 4 wheel drive …relax…dont go out of your way to twist a shaft, or over torque a universal….i have owned 4x4,s since i was a kid, my father had them i grew up around them , you can beat the balls outa them, you can get stuck and rip them up ….relax. Dont push against a curb to test it, when the time allows and you actually need 4 wheel drive its there , i have seen a lot of guys go outa there way to have an excuse to use 4 wheel drive, …..oops shit happens , be smart buddy you worked hard to get your truck. Go easy, smart youll be glad you did
David

 

[Yotota]

Well moving and throwing it into 4h did not help. Still takes considerable throttle to mount a curb. In 4L it scoots right up with no effort. Guessing the 4H is messed up. April 1 the beach permits open up here on the island so that will be a true test.

Climbing a curb is not an effective 4wd high test. There's no need to try that.

Drive somewhere that has dirt or gravel. You shouldn't be engaging 4wd on concrete/asphalt anyway.

 

[MHG]

Thanks for the responses. Just sold my lifted 25 year old Jeep XJ. Not my first rodeo as they say. The curb test was my go to any time I did work on the Jeep or my F250.

Where I live if your driving on some grass some where or gravel you are likely trespassing. This is the burbs. Nothing but homes and shopping centers. Although I guess I could go tear up the grass on the southern state parkway.

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