4 low

[Riche]

Hey guys,
A newbie to the forum here. I just bought a 1997 Z71 ext. cab. I need some transfer case advice. My 4 low is not engaging. The light just blinks. I think the front axle is engaging b/c you can feel the difference the steering in 4 hi. (i.e. the tight steering effect of the 4 wheel drive). 4 low feels the same I don’t think the trans case is changing ratios.
Any advice?

And when I start it up in the morning the first 25 feet the truck rolls I feel some kind of metal grinding noise from the front of the truck(it will only do it if it is rolling). Kind of like bad breaks(metal on metal) it only last a second. And the lights (dash & headlight) usually dim(weird???). It will not do it again until I let the truck sit for probably 4 hours.

Anyway you may think that I bought a pile but the truck is in relatively good shape the engine/trans are strong. And the exterior/interior is clean. I plan on rebuilding the front end and I fell it will be a really good truck. I would appreciate any advice with my dilemmas.

Thanks in advance!!!
Richard

[goinbig]

Do you have manual hubs on the front?

So 4 hi does work? That is interresting...I'll have to think a little about it. Maybe someone else can help.

[Riche]

Thanks for the reply goinbig.

I am assuming they are auto, whatever is stock. I don’t think it has been modified.
It doesn’t have the manual locking hubs that you have to get out and lock.

Thanks,
Richard

[Riche]

I think this weekend I am going to jack it up and put it in 4 hi and see if all wheels are turning. The 4 hi light comes on and locks in but the 4 low light just blinks for a while. And then returns to 4 hi ( I realize the potential to be on Americas funniest home videos attempting this so I will have the wife ready with the video camera!!!!!)
Anyway, hypothetical situation here. If I got the truck and didn’t know a lot about push button 4x4’s and I tried to engage 4 low in drive would that mess it up?

[goinbig]

When you jack up the vehicle, make sure that all 4 tires are completely off the ground and that no one is standing too close to the vehicle.

Where you moving when you put it in 4 low? If so, how fast were you going?

[Mikado14]

4 Lo should only be engaged in neutral and at a stop. That would be in the owner's manual but seeing as you bought the truck used, you probably don't have it.

[Riche]

I was at a full stop and in drive with my foot on the break. I hit the button and all the 4 low light did was blink.
later I found out that this wasn't the correct way. I think doing that somehow messed up the transfer case solenoid or something. How does the transfer case work does it always stay engaged and just switch from high to low?
If so I can see how my truck could still work in 4 hi and not 4 low.

Richard

[TXAGG05]

The manual suggests that you be moving less than 5mph and in neurtral. I get the most painless(quietest) shifts just barely rolling in neutral. If you are not in neutral the electronic transfer case will not shift to 4-lo. Be careful with it up on the jacks if you still have to do that.
Jeb

P.S. - oh yeah, when driving it on pavement in 4wd you are going to get some pretty nasty sounds if you turn any(especially in low), so I'd just drive straight or test it on a real loose surface.

[BrakeTorque]

What might be happening is that it shifts into 4 hi check to see if you can reach the same speed in 4lo in 1st and you will know whether or not its engaged

[Riche]

I am almost positive 4 hi is working.
and I am pretty sure the front axle is engaged.
but since the 4 low light is blinking and retuning to 4 hi I am thinking that the transfer case solenoid is not functioning properly.
I am going to use 6 jackstands to lift it up and I am not going to rev it up like an idiot. I just want to see all 4 wheels turning in 4 hi that way I know that at least that is working....
and definitely won't be crawling under it and ending up on faces of death!!!!!
in first gear it will reach the same speed while the light is blinking. I am almost positive that the transfer case is not shifting. is there a way to test the solenoid?

[skipr]

I have the 98 K1500 and it's the same set up. It's like TXAGG05 & Mikado14 said, you must be in neutral. try pressing the button several times. And also try going from 2wd to 4 low. Mine hangs up sometimes, but i'm always able to get to engage with a little persistence. And try this too, holding the 4lo button down for a couple seconds before releasing. What did you pay for this truck? and how many miles on it?

[farmboy]

Some times with the pushbutton you just have to play with it for a little while try rolling forwards and back at a very very slow speed and the gears will line up the actuator cant push them in umless its perfect

[Riche]

Ok… I am positive 4 hi works…
I took a quick look at the transfercase to see which solenoid controls the shift to 4 low. I see plenty of connections. Which one is the solenoid that shifts to 4low? I want to test the wires to see if it is getting power. If it is getting power then I may need to remove it and check actual solenoid…

Thanks guys I am getting close on this I think. I hope it is a solenoid of wiring problem and not the trans case….

[skipr]

Originally Posted by Riche

Ok… I am positive 4 hi works…
I took a quick look at the transfercase to see which solenoid controls the shift to 4 low. I see plenty of connections. Which one is the solenoid that shifts to 4low? I want to test the wires to see if it is getting power. If it is getting power then I may need to remove it and check actual solenoid…

Thanks guys I am getting close on this I think. I hope it is a solenoid of wiring problem and not the trans case….

DrkGrn/wht (dark green with a white stripe) is your 4Lo from selector switch to your transfer case control module.

[Riche]

thanks skipr,
"case control module"?
were is that?
is it the big solinoid on the bottom front of the case?