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just chillen...
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Discussion Starter #1
What is the proper way to engage the 4hi and 4lo on a 99 z71?

Now what is the proper way to disengage it?

Let me know all the secrets and what Ill feel when doing so!
 

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I slow roll my 4hi. Like 5-10 mph. Glides right in.

For 4lo I come to a complete stop, hit the button and then as it's flashing I ease off the brake until I hear it catch. No gas. Just idle slowly ahead.


Disengage 4hi/4lo I always let off the gas and hit the 2hi button. Once I feel it disengage I always come to a complete stop and then reverse for 5-10 feet. Just to be safe. It's something I've always done.

You need to be barely creepin when you disengage 4lo.

4hi will disengage much easier than 4lo.
 

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Mmm Sandwich
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4 hi can be engaged at any speed. I usually had my foot off the pedal as I was doing it thou. 4 low in neutral
 

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4 hi can be engaged at any speed. I usually had my foot off the pedal as I was doing it thou. 4 low in neutral
Do you coast slowly in neutral for 4lo engagement?

Anytime I'm at a complete stop, my truck will not lock into 4lo. I have to be barely moving for it to catch. Has always been that way. That's why I barely edge ahead in drive after I hit the button.
 

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Mmm Sandwich
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Depends if it goes in or not. Usually it went in but I have had to coast sometimes
 

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cunts
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It's better to roll in neutral if possible when engaging in 4lo. 4hi can just be shifted in at low speeds off the throttle.

Sent from the land of teepee's and buffaloes
 

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The Canadian
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4 Lo I leave in drive, just creep, no gas. 4-HI I engage at whatever speed, just normally put it in neutral, click it in, then put back in drive (even at 80-100 km/h). Never given me a problem. NEVER leave it in Auto 4wd
 

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This place sucks dicks
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My particular year of truck must be different. It wont even attempt to shift into 4low unless the trans is in neutral.
 

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cunts
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Mine is the same way as Bart's. Absolutely will not shift into 4lo until trans is in neutral. My 96 Yukon would shift into 4lo while in drive iirc, but even then I would still put it in neutral. Just less undue stress.
 

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My particular year of truck must be different. It wont even attempt to shift into 4low unless the trans is in neutral.
What year?

My 4lo is very touchy. I find that if I push the button while stopped (in drive) as soon as I let off the brake it normally catches immediately. But if I remain on the brake it will just flash @ me. If it doesn't catch as soon as I remove my foot from the brake then sometimes it just doesn't catch.

There are times when I miss the old floor-shift days.
 

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Mmm Sandwich
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What year?

My 4lo is very touchy. I find that if I push the button while stopped (in drive) as soon as I let off the brake it normally catches immediately. But if I remain on the brake it will just flash @ me. If it doesn't catch as soon as I remove my foot from the brake then sometimes it just doesn't catch.

There are times when I miss the old floor-shift days.
That may be because according to the owners manual it should be in neutral or park when putting it in 4lo
 

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That may be because according to the owners manual it should be in neutral or park when putting it in 4lo
Well, I should be a little more specific then I guess.

If I am at a complete stop, whether it be drive, neutral, or in park, it will not engage. It's as if the gears don't mesh or something. Seems like a luck of the draw situation when in N or P on whether the gears line up.

9/10 if I leave it in drive and do as I mentioned it will "clunk" right in.


But it is an 11 year old truck. So it prolly doesn't function as properly as it did when new.
 

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That's pretty much spot on for what I do.

Like I said, I leave it in {D}, come to a complete stop, push the button, then as it's flashing I ease off the brake. Catches immediately.

But maybe I'll try and do a slow roll in neutral next time I try it. I've maybe been in 4lo 5-6 times since owning this truck. Maybe.
Its not exactly spot on - because you don't shift it into neutral which the directions say you have to.

It says you can be moving but still must shift the trans into neutral.

I still have a fooked up switch. So sometimes after using Autox4 and switching back to 2wd for awhile I'll come out in the morning and start truck and it will have shifted itself into 4low.
 

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just chillen...
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Discussion Starter #17
Thank y'all sorry it took so long
 
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