How to Replace Four Wheel Drive Actuator 01-14 GMC Sierra 2500

[@1AAuto]

√ *Watch the Video* √ *Buy The Part at 1A Auto* 1aau.to/m/Visit-1AAuto √ *Do it Yourself* √ *Save Money*

[@1southsoon]

Thank you for the reply. My truck is actually an 02 Avalanche 2500. Today I looked and found that I have an actuator on the transfer case. I did your test and listened for the actuator sound and heard nothing. After a little more research I found that the ground wires on the frame under the drivers door were never tightened at the factory. After a few turns of a ratchet the truck shifts flawlessly. Good luck with your part business. Putting out the videos is a great idea to help sales.

[@stevenchan1057]

The owner at the beginning of the video looks so comfortable in front of the camera. And he speaks so well. Not like reading from a script at all.

[@1AAuto]

@02CamoZ71 You may want to check under the hood for broken or frayed vacuum lines to see if any of them are broke. If you do find one fix it and see if it helps. A lot of times many different vehicles use vacuum to also help engage the 4WD system, and if there's a leak it may not fully engage. Hope this helps you out.

[@1AAuto]

It could be, in the system runs off of vacuum, check the vacuum lines to see if any of them have a crack or are broken and need to be replaced. Hope this helps you out.

[@1AAuto]

@pitty4cly It could be the actuator, or possible the hubs having a hard time engaging. I would also check for any unplugged, loose or cracked vacuum lines under the hood.

[@1AAuto]

@yobie732 Once you loosen the nut the whole unit should come right out as shown in the video. If you look at the end of the actuator in th video there is some fluid on it. Not sure if part of the actuator has snapped off on you and is stuck in the housing. Hope this helps out.

[@vincentfontana8325]

Love the safety used in this video. No glasses but he squints to protect his eyes while using air tools

[@1AAuto]

+Vincent Fontana Thanks for checking us out! 1aau.to/m/Shop-1AAuto-c

[@1AAuto]

HI Tony, I would check the vacuum lines under the hood to see if there's possibly a vacuum leak which may be causing the 4wd to not fully engage.

[@1AAuto]

@1973Rhoda You may want to check the threads where the new actuator screws into to see if there's anything caught in them.

[@1AAuto]

@Jonathan11347 Possibly could be an issue with the hub mechanism?

[@1AAuto]

It should break free for you as shown in the video. Is the nut on the actuator stripped from the wrench slipping on it? If it is and you can't get a good bit on the plastic, you may be able to use a pipe wrench to break it free.

[@1AAuto]

@pooh3700 It could be the actuator. You may also want to inspect all of your vacuum lines in the engine bay to see if there are any broke or disconnected ones that could be causing the issue. Hope this helps you out.

[@1AAuto]

Sounds almost as if the shift motor is not properly engaging on the transfer case. I would suggest checking out the motor itself and see if it is clicking over far enough to engage the transfer case gearing.

[@1AAuto]

@imaniguana You could try to check your vacuum lines to see if there's a leak at all in them. If there is that may cause the system to hang up. If it is stuck in 4WD you should be able to feel the front end hop when you take a turn.

[@1AAuto]

@Davaith That could be a bad wheel bearing. You may want to check them to see if they're worn.

[@1AAuto]

@cheekster96 it might be. If there's a check engine light on also I would have the code scanned to see what may be causing it.

[@1AAuto]

@TheMaxamise You may want to check it to see if there's anything blocking it or you may also want to check the fuses to see if one of them are blown.

[@1AAuto]

You may want to inspect the CV axle to see if it needs to be replaced. I would also check the transfer case to see if anything needs to be replaced on it.

[@1AAuto]

@personman8 You may want to check the hubs to see if it's trying to engage.

[@JipJac]

Man! Thanks for this video. Very helpful for someone who who is not a mechanic like myself. Was discussing with a friend just now about how my 1500 HD hasn't been engaging the 4WD and he told me about this. A google search led me here. Great video!

[@1AAuto]

@algid4 You may want to scan the computer for any codes that may be generated. If there are any, it should point you in the direction of what's causing the issue.

[@1AAuto]

You could test the power going to the actuator with a test light. If there's a check engine light on, you may want to have the code pulled to see what it's pointing to.

[@1AAuto]

You may want to check the vacuum lines under the hood to see if they are split or attached. You could also see if there are any stored codes in the system that might tell you what's causing the issue.

[@1AAuto]

It could be. You may want to hook a scanner up to it, to see if there are stored codes that may tell you what's acting up.

[@1AAuto]

@Dudedaaman It could be. You may also want to have the computer scanned to see what the culprit might be. If there's a code stored, it should tell you what it is.

[@1AAuto]

You may want to check the CV or U joints in the front axles to see if they are freezing up. Hope this helps you out.

[@1AAuto]

If the system happens to have any kind of vacuum lines that connect to it, you may want o see if there's any type of a leak in it.

[@1AAuto]

If the vacuum line has become unplugged from something that could be what's triggering the light. You could also have the code pulled to see what it's pointing to.

[@1AAuto]

@MrTarkus007 electrical items such as this can't be returned once they are installed on the vehicle.

[@1AAuto]

@XBraidenX0121 You may want to check the hubs to see if there's an issue with them not engaging.

[@1AAuto]

@MrTarkus007 Where it's that cold outside, you may want to let the truck sit at idle for a while and let the motor and transmission warm up for a while, with the heat on in the cab. It may just be frozen in place and need to be warmed up. Hope this helps you out.

[@1AAuto]

You may want to check the switch, and also the actuator to see if they are working okay and have power to them.

[@1AAuto]

@02CamoZ71 Sometimes the light will blink and the truck will not engage into 4WD.

[@1AAuto]

@stephen123453 If you're asking how much it would be to do a 2WD to 4WD conversion, it may be pretty costly.

[@1AAuto]

Both of those codes point to an EVAP leak. It could be the gas cap or possibly the canister valve.

[@1AAuto]

It could definitely be the the issue but it could also be the transfer case shift motor. You might want to see if the motor is working first and then see if the actuator is pushing out when you hit the 4hi.

[@1AAuto]

There could be either a fault with the transfer case, shift motor or the front differential. Bringing it into the shop and having them read the codes will be the best bet at this point.

[@badgn2002]

2003 Yukon 2500. 2 HI, 4 HI and 2 Low lights all work on dash. I can hear the transfer case motor working. I can feel the truck drag when engaging the transfer case. Drained the fluid in the transfer case all looks good. My mechanic confirmed the output from the transfer case spins the front drive shaft. The front wheels spin on the lift. But under load no 4wd. I am replacing the front axle actuator. I bet this is the issue. Thanks!

[@squarecrawler9551]

raymond sherman did the front actuator fix the issue? I have same Exact problem

[@1AAuto]

You may want to monitor it to see if it does it again on you. If it does it could be the actuator that's getting tired.

[@1AAuto]

@33brianw It may. You may also want to look for a pinched wire somewhere that might be causing the issue too.

[@1AAuto]

The issue could be with the transfer case shift motor not working correctly so the light is not switching out of the 4Lo.

[@1AAuto]

@oneloudchevy32 If it tries to engage but does not engage all of the way you might want to check under the hood for a loose of broken vacuum line. If there is one that's broke it may keep the 4WD system from engaging all of the way. Hope this helps you out.

[@1AAuto]

You could try to turn the front tires by hand to see if they are rubbing of catching on anything.

[@1AAuto]

You may want to inspect the locking mechanism(s) for the front hubs to see if they are worn.

[@1AAuto]

You may want to check the wiring to see if there's power going to the actuator.

[@1AAuto]

@jmf96763 I would check all of the fluid levels and also have the code ran in the computer to see what's causing the issue.

[@1AAuto]

It may be the actuator. If there's a check engine light on also, you may want to pull tthe code to see what it points to.

[@1AAuto]

It's possible. Sometimes if you back down the road in reverse a few feet, it may disengauge for you.

[@1AAuto]

We currently do not have a video for that particular year. You may be able to apply some of the basic steps shown in this video to your application.

[@OSCARANDRES039]

Thank you for your video. I recently replaced the actuator motor and I had some oil coming out from the hole. Is that normal ???

[@1AAuto]

@2allendorf82 It may be due to a bad axle shift actuator you may want to take a look at it to see if has gone bad. Here's a link to them on our site if you need one. Hope this helps you out. www.1aauto.com/1999-chevy-k1500-truck-4wd-parts/y-mo-c/1999-1518-30?VideoReply&Forum&ATony

[@1AAuto]

@madbeto73 I would have to code ran to see what's causing the issue.

[@1AAuto]

If you have a portion of the actuator stuck in the front differential, you will have to probably find a way to wedge something inside the part so you can spin the damaged portion out.

[@mattparks11]

would a bad actuator cause the “service 4x4” light to come on and then a ticking noise when the truck is moving?

[@1AAuto]

+Matt Parks We wouldn't be able to diagnose an issue like that here, you may want to have a local mechanic take a look at it. Thanks for checking us out! 1AAuto.com

[@1AAuto]

You may want to check the switch to see if it's working correctly.

[@1AAuto]

You could check it to see if it's acting up.

[@1AAuto]

You may want take a look at the look at the transfer case to see if it was damaged.

[@MYbabyGLOCK30]

Have a 99 silverado z71 and i push the button but it just makes a clicking sound. It sounds like it is trying to go in but doesn't. That sound like the actuator to you?

[@Terceira73]

i tried putting my 4wd on while driving at a low speed it made a grinding noise and was working after that.could it be the actuator or something else?Your input would be greatly appreciated.

[@1AAuto]

Make sure that the actuator has power or vacuum to it.

[@1AAuto]

Then the issue might be related to the linkage not being in the correct position.

[@1AAuto]

HI Ben, It sounds like the computer is trying to remind you to possibly change the fluid or something. You may want to check the owners manual for recommended fluid changes.

[@1AAuto]

@TheMaxamise Also under the hood of the truck, check the vacuum lines to see if any of them are broke or split. If they are replace them, and this may solve the issue that you're having. I had a 96 Jimmy that this happened to, the 4WD would not fully engage, and it ended up being a broken vacuum line on the drivers side in the engine compartment. hope this helps you out.

[@1AAuto]

We don't have a vacuum or wire diagram for this vehicle. It could just be a weak actuator.

[@georgeferris6305]

Thanks!

[@ArmaAceChannel]

anyone recommend dropping the whole front axle for replacing the oil pan gasket?

[@ItsthePittsfrom81-83]

Hello great vid ! I have 02 Chevy Trailblazer. Which is mainly driven in two wheel drive. But when switched to all wheel or 4x4, Will made a weird grinding noise for a few seconds like bearing noises. Then completely go out like neutral with no movement in any gear the i switch it back to 2 wheel. its fine and then back to 4x4 it works again like no problem. It only does this randomly not all the time. Any help would be appreciated.

[@1AAuto]

If it's not working, you should make sure that there's power going to the actuator.

[@1AAuto]

The axle actuator on your F150 is made a lot differently. Here's the part number for it on our website with a picture of the part. Part Number: 1AFWA00008 1aauto.com 888-844-3393

[@schmidt311]

Hi, quick question... I replaced the actuator this afternoon, and it didn't change anything. Do I have to have to programmed before it communicates with the truck's computer (2004 Tahoe Z71)?

[@MrTarkus007]

thank you for the respond but in case i let it warm up per say 15 - 20 min. &it still wont shift what do you think it could be? the actuator ? it's never done this before it always went smothly into gear ...

[@1AAuto]

We currently do not have a video for that particular repair. We'll keep this request in mind during any future repairs that we may make to this vehicle.

[@ArizonaHeatRacing]

Is this to be replaced when 4x4 service ligh come on and does let you u go into 4WD ?

[@ccastleman9515]

got a brain buster for you .. I have a 05 gmc manual tranny . manual 4 wheel drive . my front axle is hopping and chattering in tight parking lot turns . i'm in 2 wheel drive but its like my axle is still locked in . is this possibly that actuator stuck?

[@algid4]

@1aauto i have a 1999 chev blazer 4x4, there is a dash in my car saying 4x4 service, it dose go off and came back on again, now its always on, when it dose go on 4x4 doesn't work, am not sure if its just the switch or the axle Actuator or something else.

[@Balmond1986]

I have a 2002 gmc 1500 z71 4x4 I replaced cv axles and hubs recently and we just got a first snow and went to turn the 4 wheel hi on (push button ) the light flashes says in 4wd and feels like it is 4 wheel (maybe on one side) but it makes a rubbing/grinding nosie does it worst turning the wheel too what could it be ? Mind u I can't hear the transfer case to engage either ÷

[@1AAuto]

You may want to check the vacuum lines in the engine compartment around the firewall. If there's a leak or a broken vacuum line, it may be causing this issue. If this isn't the case, it could possibly be a bad actuator. Hope this helps you out. 1aauto.com 866-403-3393

[@victorryemundo8595]

Where do those wires run to? I just purchased a truck and there are no wires connected to it. Thanks for any help you may have to offer.

[@cheekster96]

I have a 2004 1500 GMC W/T with the manual shift 4wd. The 4wd indicator on the dash wont go out (I can shift in and out of 4wd still). I ended up taking the fuse out so the idiot light wont stay on all the time. Only problem is, when I go into 4wd, the light is out. Do you think I have a bad solenoid? Lee

[@rodrigoantioco8704]

Hello i have a question my transfer case engages into 4x4 and locks the front drive shaft but fron axle isnt locking could it be the actuator

[@1AAuto]

There were two different types of actuators that came on those trucks. Some of them were an axle actuator and some of them were mounted on the transfer case. You can either check under the truck to see what type your truck has, or if you give the dealer your VIN # they could tell you what type your truck has. We carry both types on our website 1aauto.com 888-8944-3393

[@MrAjd1982]

now mine (2005 Tahoe LS) goes into 4hi and auto fine, it's just the 4lo, i can hear the case trying to transfer over to 4lo but then just goes back to 2wd, would the actuator still be a cause with those symptoms

[@canadiancryptidscanadasbea8335]

Hi Mike I am having trouble with my 4x4 on my 2000 gm 2500 I have replaced the actuator and have my truck blocked up the front tires turn when 4x4is engaged As soon as I put my hand on the either front tire it stops turning any pressure at all stops the tires any suggestions

[@1AAuto]

@MrTarkus007 If that doesn't free it up it may be the actuator.

[@waverider48]

1A Auto Parts, I was following this video to help replace the actuator in my 2002 gmc 2500hd, when I took out he old actuator it came out very hard, and there was plastic strips coming off the threads. I tried to screw the new actuator in but it would not go in, it was kinda catch but then pop back off the threads. It started to go in once but was very hard, I pulled it out and the first line of threads was stipped completly off...what would cause that? was is the wrong actuator? It looked exactly like the one that was on there. I believe then one I had as the good one was from an older truck like a 98 chevy 1500 with push button 4x4

[@humptydumpty8976]

What about on 2015 models

[@1southsoon]

Just watched your other video which I believe was an actuator replacement on a 1500. I have an '02 2500 that has been stubborn to switch between Hi to Lo for some time now. Today it went into Lo and is stuck there. I need to change the actuator. Does my truck have both the axle actuator and the transfer case actuator? I would think that if it does that the other (transfer case actuator) is at fault. What should I change? Thank you again for the great videos.

[@1AAuto]

If there's a grinding noise in the front axle when the 4x4 is engaged, you may want to check the front axles to see if they have any play in them. You could also take the axles out of the differential and inspect them for damage to see if that could be causing the issue. Hope this helps you out. 1aauto.com 888-844-3393

[@marcb8002]

When I removed my actuator oil started seeping out. Oil looked milky like it was contaminated with water. How would water get in? I'm planning on replacing all the oil, but don't want it happening again. Great video, helped me figure out what was not working on my 2006 silverado 2500hd.

[@HarryBeast55]

Check /extended your breather vent further up into the engine bay

[@HarryBeast55]

Could also have been airation of the fluid or just moisture

[@ronnieinbama]

Hello 1aauto, when my 90 Chevy is shifted in 4 wheel low it will cause the gears to slow the speed range down drastically yet I cannot get the front tires to spin no matter what the road surface is. *I am not positive if it's high or low range because I haven't had the truck long and haven't messed with the 4 wheel drive yet. It is closest to the firewall* Any suggestions for this problem?

[@Jhaza01]

I have a 2004 silverado Z71. Driving through snow just a few days ago, I heard a clunking sound, and from then on, there was no power to the front wheels. My 4x4 is manual shift, and the dash lights do come on, but again, no power to the front. Suggestions where to start? I've called around to get some ideas, and all I keep hearing is "you need a new transfer case", or "you need a new front differential", or "you need a new ........." you get the point. I need this fixed.

[@MrAjd1982]

i thought i read somewhere that the electronic 4x4 tahoes don't use vacuum lines, i thought its all electronic, hence why it has an actuator, idk could be wrong, do you know where i could get a diagram of what vacuum lines serve for the 4x4, thanks

[@1AAuto]

@68softtop Axle is coming in not too distant future.

[@chachifeere]

mine goes in but sometimes get stuck and wont switch out of 4x4 ??? is it the actuator or dash switch

[@imaniguana]

I have an 03 Avalanche z71 1500. The front differential is engaged all the time, yet the 2WD button is lit. I've tried switching through all kinds of combinations 4 HI, 4 LO, 2HI, neutral, but I can't get the front differential to disengage. I took it to one mechanic and he said it's not engaged and there's nothing wrong, yet I hear all the front differential sound when I'm driving and my gas mileage indicates it's engaged. What do you think the problem could be?

[@winsorcrocker9911]

Hello, What if I don't have the 4x4 dash light on and no 4x4. I feel the solenoid when I put my hand on it and my wife goes through the 4x4 gears?

[@winsorcrocker9911]

02 Sierra manual 4x4 shift

[@1AAuto]

@motocross817 Stay tuned!

[@mikearduini6315]

I have a 2003 Silverado and need to replace the actuator. My nephew and I tried to get it off but it wouldn’t budge. What do I need to do to get it out?

[@Varbet350]

My 99 suburban says service 4x4. The buttons change lights when u switch it. But could it be the actuator? The Guy I bought it from said the transfer case looked brand new.

[@jerrybanks6601]

2000 Chevy Tahoe. Service 4WD light comes on after about a minute in 4WD Hi. Need to turn off ignition then back on to change back to 2WD. I bought a switch from you folks and swapped out the original. Cleaned the ground connection on the frame. Checked both the 4WD and ATC fuses. Still no joy. Suggestions very welcome. Thanks.

[@1AAuto]

+Jerry Banks Thank you for your comment and your order! If you are unsure what is wrong with your 4x4 system we strongly suggest you have a trusted mechanic take a look at the vehicle. It could be a multitude of things causing this issue, and we would have no way to give you a somewhat accurate answer. 1aauto.com