Question about 1998 GMC Jimmy

1 Answer

Intermittent 4wd on 98 jimmy

Changed the vacuum actuator. changed the electric shift motor on the transfer case. changed the vacuum switch on the transfer case. went into 4wd easily. drove a little. stopped. pushed 4wd low button. went in but lights flashed and the transmission would not shift out of low gear. as i slowed down it shifted back into 2wd with a clunk and now will not go into 4wd but sometimes into low with lights flashing. possibly drive line computer under kick panel? thanks. Jeff

Posted by on

  • Anonymous Mar 20, 2014

    I can feel the transmission shifting and transfer case changing to low and back to high ,I can see the actuator moving in and out but the front wheels don't engage. gears are good in nthe differential

×

1 Answer

  • Level 2:

    An expert who has achieved level 2 by getting 100 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Expert
  • 260 Answers

The module is what i would suspect. and i do believe it is in the r kick panel. i've seen the button pack on dash go bad too, but module is best bet.

Posted on Nov 16, 2008

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

My 98 f150 was in 4WD Hi this morning when I started it. Selector switch is in 2WD position. 4WD Hi light is on, hubs (or front differential) is engaged and transfer case engage. (Feel front wheel hop...


If the switch was in the 2WD position and the transfer case was locked in a 4WD range, my 2 SWAGs would be bad switch or the connector to the shift motor is damaged / corroded or the fuse to the transfer case shift relay module is blown ( fuse # 17 ) / problem with the transfer case shift relay module.

This is without knowing if the truck was used in 4WD the night prior, and shifted out just before turning off. If this is the case, the shift motor might be stuck, and a few hits with a dead blow hammer to the transfer case might jar it free again ( do not use a metal hammer, it could damage the transfer case ).

The vacuum shift solenoids on the firewall are controlled by the GEM ( Generic Electronic Module ) which is grounding either the 2WD or 4WD solenoid, depending on the shift plate contacts in the transfer case. ( when in 4 or 4H, the contact switch plate signals the GEM, which in turn grounds the correct solenoid ).

Pulling the switch will not cause the transfer case to go back to a default position, the switch has a resistance level for each mode, and needs that value to operate the shift motor.

The resistance values for the switch between the 2 dark blue wires:
2WD - 4100 to 3700 ohms
4H - 1050 to 1150 ohms
4L - 380 to 340 ohms
- find the wire locations on the switch, mark them and remove the connector to test the resistance.

Just my opinion on the order :

1. Check the fuses for the shift motor
2. Try the old school shift method, back up ~ 50' put into park or neutral, and shift from 4WD to 2WD.
2.1. This is to see if the transfer case shift motor is bound up, and reversing might release it
3. Try hammering the transfer case with a dead blow hammer while someone shifts from 2WD to 4WD. You only need the key in the run position, if it happens quick enough after running the engine, the vacuum reservoir will still have enough vac to operate the solenoids. Don't chance running yourself over.
3.1. If this frees up the shift motor and the vacuum has bled off, you can try starting the truck and shifting into 4H then back to 2WD to get the front axle to disconnect or manually vacuum operate the front disconnect motor by applying vacuum to the pink vacuum line on the shift motor on the front axle.

Mar 05, 2011 | 1998 Ford F150 Regular Cab

1 Answer

4x4 push button is not working about how much does


This is something you can do yourself if you have ever worked on a vehicle before. The part you need is called a front drive actuator valve. It costs about $ 50.00, GM part # 15165891.
Here is some more infor about it:

Main 4wd Components:
TCCM
- Transfer Case Control Module - Located behind the glove box. This is the electronic 'brains' behind the shifting.
Switch - The push button switch in the dash - driver input/indicator.
Encoder Motor - Located on the transfer case - This is what actually shifts the transfer case, and tells the TCCM what position it is in.
Vacuum Switch - Also located on the transfer case - This is what sends vacuum to the vacuum actuator (see below) when the transfer care is in 4HI or 4LO.
Vacuum Actuator - Located under the battery tray - This is what engages or disengages the front driveshaft.
Front Axle Switch - Located on the front axle - This is what tells the TCCM when the front axle is engaged.

If you want to try and replace it yourself, please let me know how it goes.

Feb 11, 2010 | 1998 GMC Jimmy

1 Answer

I have a 1995 Silverado 4x4. The 4WD will not engage. Someone told me it may be the actuator for the transfer case. When I try to shift into 4hi, nothing happens. When I try to shift into 4lo, it grinds...


I HAD A BLAZER WITH THE SAME SYMPTOMS REPLACED THE TRANSFER CASE MOTOR AND SOLVED PROBLEM. TRANSFER CASE MOTOR SHIFTS FROM HIGH TO LOW GEAR IN THE TRANSFER CASE AND TELLS THE FRONT ACTUATORS TO INGAGE FRONT HUBS . MOTOR WON'T MOVE TO 4 HIGH AND GRINDS WHEN TRYING TO MOVE TO 4 LOW, TRANSFER CASE MOTOR FAILING . CHECK VACUUM LINES AND ACTUATORS ON FRONT DIFF THEY FAIL, CAN CHANGE TO CABLE ENGAGEMENT INSTEAD OF FAILURE PRONE VACUUM ACTUATORS.

Jan 23, 2010 | 1999 Chevrolet Silverado 1500

2 Answers

Four wheel drive will not engage when truck is warmed up.sometimes it will engage usually when truck is cold????


On the full size, the front actuator is electric, not vacuum.

When in 4wd mode, a switch on top of the transfer case conducts 12 volts out to the actuator. Wire #50 (brown) is the 12v feed, and it conducts to the light blue wire (#900) to the actuator.
When shifted out of 4wd, the switch opens up and no voltage goes to the actuator.

Check voltage at the connector for the front actuator (at the front differential - it looks like a large bullet that threads into the front diff.) If it has 12 volts, the actuator is the problem. If it does not have 12 volts, check the transfer case switch and the power feed to the transfer case.

I'll assume it is the actuator, if the plug to the actuator is getting 12 volts when in 4wd.
The way this actuator works, is it is a sealed chamber that gets heated by voltage. When it heats, the pin in the end swells and pushes a shift fork in the front differential. The shift fork engages a spline on the passenger side of the differential, and boom! you have 4WD.

GM offered an upgrade to this actuator that is a motor instead of a heated device. However, it requires a small harness addition, a spacer, and a new actuator. It is about a $150 to $200 option.

Good luck. The actuator is usually the problem 90% of time but recheck all of the wire harness just to maker sure there is no short before replacing any parts.

88-UP C/K ACTUATOR UPGRADE
VEHICLE SERVICED: 1994 CHEVROLET FULL SIZE
PURPOSE: IMPROVE AXLE CONNECT ENGAGEMENT TIME AND
COMPONENT RELIABILITY.

SYMPTOMS: NO FRONT DRIVE AXLE ENGAGEMENT WHEN SHIFTED
INTO 4X4.

Obtain the following GM part numbers:
(1) 26060073 Actuator
(1) 88959465 Harness/Spacer Kit

Jan 10, 2010 | 1999 Chevrolet K1500

1 Answer

1991 K2500 pickup, 350tbi,4l80 trans, 4wd not working, I have gotten it to turn on a couple of times but it never stays working. The transfer case does lock in when its put into 4wd. also the actuator is...


On the full size, the front actuator is electric, not vacuum.

When in 4wd mode, a switch on top of the transfer case conducts 12 volts out to the actuator. Wire #50 (brown) is the 12v feed, and it conducts to the light blue wire (#900) to the actuator.
When shifted out of 4wd, the switch opens up and no voltage goes to the actuator.

Check voltage at the connector for the front actuator (at the front differential - it looks like a large bullet that threads into the front diff.) If it has 12 volts, the actuator is the problem. If it does not have 12 volts, check the transfer case switch and the power feed to the transfer case.

I'll assume it is the actuator, if the plug to the actuator is getting 12 volts when in 4wd.
The way this actuator works, is it is a sealed chamber that gets heated by voltage. When it heats, the pin in the end swells and pushes a shift fork in the front differential. The shift fork engages a spline on the passenger side of the differential, and boom! you have 4WD.

GM offered an upgrade to this actuator that is a motor instead of a heated device. However, it requires a small harness addition, a spacer, and a new actuator. It is about a $150 to $200 option.

Good luck. The actuator is usually the problem 90% of time but recheck all of the wire harness just to maker sure there is no short before replacing any parts.

88-UP C/K ACTUATOR UPGRADE
VEHICLE SERVICED: 1994 CHEVROLET FULL SIZE
PURPOSE: IMPROVE AXLE CONNECT ENGAGEMENT TIME AND
COMPONENT RELIABILITY.

SYMPTOMS: NO FRONT DRIVE AXLE ENGAGEMENT WHEN SHIFTED
INTO 4X4.

Obtain the following GM part numbers:
(1) 26060073 Actuator
(1) 88959465 Harness/Spacer Kit

Jan 10, 2010 | 1991 Chevrolet K2500

1 Answer

Had 2001 GMC Sierra in 4WD Auto and went to put in 4 hi. then Service 4WD light came on and selector wouldn't let me select anything and the truck stayed in 2 hi.


On the full size, the front actuator is electric, not vacuum.

When in 4wd mode, a switch on top of the transfer case conducts 12 volts out to the actuator. Wire #50 (brown) is the 12v feed, and it conducts to the light blue wire (#900) to the actuator.
When shifted out of 4wd, the switch opens up and no voltage goes to the actuator.

Check voltage at the connector for the front actuator (at the front differential - it looks like a large bullet that threads into the front diff.) If it has 12 volts, the actuator is the problem. If it does not have 12 volts, check the transfer case switch and the power feed to the transfer case.

I'll assume it is the actuator, if the plug to the actuator is getting 12 volts when in 4wd.
The way this actuator works, is it is a sealed chamber that gets heated by voltage. When it heats, the pin in the end swells and pushes a shift fork in the front differential. The shift fork engages a spline on the passenger side of the differential, and boom! you have 4WD.

GM offered an upgrade to this actuator that is a motor instead of a heated device. However, it requires a small harness addition, a spacer, and a new actuator. It is about a $150 to $200 option.

Good luck. The actuator is usually the problem 90% of time but recheck all of the wire harness just to maker sure there is no short before replacing any parts.

Jan 07, 2010 | 2001 GMC Sierra Crew Cab

1 Answer

The 4wd wont disingauge back to 2wd i jacked up driverside front tire while motor was running pushed 2wd button turned wheel till it catches wont come out


Check the fuse to the 4x4, if the fuse is good then check the 4x4 electric motor actuator on the transfer case. You should hear it work from 2wd, 4hi to 4low and back to 2wd with the push of the switch. if you don't hear it working then check the wire harness at the actuator motor, look for any damages like corrosion or cracked wire connector clips. If the 4x4 actuator is working on the transfer case. There is a vacuum switch on the top of the transfer case, driver side but when that fails, your front hub stay's locked in the on position. Good luck and keep me posted and hope it's a simple fuse that has gone bad. You can pick up all these parts at Auto Zone or Parts Source and they will have the step by step instructions for you to get the job done with common tools. Replacing the vacuum switch on top of the transfer case take about 15 min to replace if you don't have to jack up the Jimmy if not 30 min if you have to jack it up. Be safe and keep me posted, be glad to know your go it working again.

Jan 06, 2010 | 1999 GMC Jimmy

1 Answer

2004 chevy 3500 dually 4X4 front axle not working and no light showing 4X4


On the full size, the front actuator is electric, not vacuum.

When in 4wd mode, a switch on top of the transfer case conducts 12 volts out to the actuator. Wire #50 (brown) is the 12v feed, and it conducts to the light blue wire (#900) to the actuator.
When shifted out of 4wd, the switch opens up and no voltage goes to the actuator.

Check voltage at the connector for the front actuator (at the front differential - it looks like a large bullet that threads into the front diff.) If it has 12 volts, the actuator is the problem. If it does not have 12 volts, check the transfer case switch and the power feed to the transfer case.

I'll assume it is the actuator, if the plug to the actuator is getting 12 volts when in 4wd.
The way this actuator works, is it is a sealed chamber that gets heated by voltage. When it heats, the pin in the end swells and pushes a shift fork in the front differential. The shift fork engages a spline on the passenger side of the differential, and boom! you have 4WD.

GM offered an upgrade to this actuator that is a motor instead of a heated device. However, it requires a small harness addition, a spacer, and a new actuator. It is about a $150 to $200 option.

If I were you, I would buy a new heated actuator. They are available at most auto parts stores, and are about $90. They are also on eBay for about $55 plus shipping. These are very easy to change - just thread out the old one, and thread in a new one.

Good luck, That actuator is usually the problem 90% of time.

Dec 28, 2009 | 2001 Chevrolet Silverado 2500HD

1 Answer

4wd will not engage, or engages intermittently. You can hear the click of a switch under or near the battery, but doesn't always engage.


Hi:
The main parts to the 4WD system are the transfer case, the shift control motor, and the shift control module. if you remove the shift control motor from the transfer case, and leave it plugged into the harness, you should be able to see if it functions thru all settings, such as 4wd high or low or 2wd. If not, then you need to figure out which part is bad, the motor or the control module. If it does work as it should, then you have some sort of transfer case problem.

Dec 10, 2009 | 1996 GMC Jimmy

1 Answer

01 suburban 4x4 wont work.


On the full size, the front actuator is electric, not vacuum.

When in 4wd mode, a switch on top of the transfer case conducts 12 volts out to the actuator. Wire #50 (brown) is the 12v feed, and it conducts to the light blue wire (#900) to the actuator.
When shifted out of 4wd, the switch opens up and no voltage goes to the actuator.

Check voltage at the connector for the front actuator (at the front differential - it looks like a large bullet that threads into the front diff.) If it has 12 volts, the actuator is the problem. If it does not have 12 volts, check the transfer case switch and the power feed to the transfer case.

I'll assume it is the actuator, if the plug to the actuator is getting 12 volts when in 4wd.
The way this actuator works, is it is a sealed chamber that gets heated by voltage. When it heats, the pin in the end swells and pushes a shift fork in the front differential. The shift fork engages a spline on the passenger side of the differential, and boom! you have 4WD.

GM offered an upgrade to this actuator that is a motor instead of a heated device. However, it requires a small harness addition, a spacer, and a new actuator. It is about a $150 to $200 option.

If I were you, I would buy a new heated actuator. They are available at most auto parts stores, and are about $90. They are also on eBay for about $55 plus shipping. These are very easy to change - just thread out the old one, and thread in a new one.

Good luck, That actuator is usually the problem 90% of time.

Dec 09, 2009 | 2001 Chevrolet Suburban

Not finding what you are looking for?
1998 GMC Jimmy Logo

580 people viewed this question

Ask a Question

Usually answered in minutes!

Top GMC Experts

yadayada
yadayada

Level 3 Expert

64034 Answers

Freddy

Level 3 Expert

1311 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

21990 Answers

Are you a GMC Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...