Question about GMC Cars & Trucks

1 Answer

91 gmc Sierra k1500 My 4wd when I lock it in is engaging the lower gear abut not the front wheels. It is a manual 5.7 the hubs are automatic locking and the 4wd shifter is on the floor. I am replacing the cv axles and hubs anyways but still want to know any ideas.

Posted by on

Ad

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • GMC Master
  • 5,324 Answers

I think you have a separate actuator on the front diff which operates off vacuum. The vacuum can is under the battery tray and any lines leaking can cause this issue.

Posted on May 05, 2015

Ad

3 Suggested Answers

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

Ad
  • 78 Answers

SOURCE: four wheel won't engage

Theres a vacume dash pot under the battery box. It pulls a cable that engages the front diff. Put the vacume line and you'll have lights and four wheel drive. (it happened to my blazzer)

Posted on Dec 29, 2008

  • 1 Answer

SOURCE: I have a 1994 gmc 4x4 and the front axles wont engage

If Your Front CV shaft is broken it will not engage...Shaft can be in visibly good shape, but you might hear a knocking sound or a shutter when turning sharply. I had this problem this last winter. Get under the truck and try and turn the CV by hand. if it can be rotated, it is bad.

Posted on Jul 05, 2010

Add Your Answer

Uploading: 0%

my-video-file.mp4

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

×

Loading...
Loading...

Related Questions:

1 Answer

4wd front wheels not turning


have you got automatic locking hubs or manual locking hubs that you have to turn 90 degrees for the locks to engage.

Jan 21, 2014 | Cars & Trucks

2 Answers

Front drive shaft not fully engaged in 4WD, with truck on stands all 4 wheels do rotate but if i stop front wheels the front drive shaft is not engaged


Hi,
Do you have auto locking hubs on the front wheels, or manual locking hubs?
If you have auto locking hubs chances are they are not engaging properly and will need to be removed and spline sets checked for broken teeth on locking hub and locking shaft.
If you have manual locking hubs then check that they are firm when turning to engage them in the lock position.If they are light when engaging them to the lock position then they my have broken/worn out the locking hub and spline. Also check that the engaging spring inside the hub has enough tension to engage the hubs they may be broken. If the hub are all ok then you have a problem in the transfer box, where the 4WD lever is not meshing the transfer box properly. Hope this helps, let me know how you get on.

Jason

Apr 04, 2010 | 2002 GMC Sierra C/K1500

1 Answer

I have a 1997 gmc pickup with 4-wheel drive. The


You probably have blown drive hubs. Do you have to engage the hubs at the wheels? If not and they are automatic locking and they are probably blown or seized into the unlock position. They are not too expensive to replace with manual locking hubs (My Suggestion) but the autolocking hubs are expensive. When you take the caps off the front drive spindles and try running it again you may see the axle turning inside but not the wheel. That is the best test. Wish you luck!!

Jan 05, 2010 | 1997 GMC Sierra K2500

1 Answer

95 dodge 2500 4x4 front axle clicks in 2wd not 4wd when engaged


Do you have automatic locking hubs? Do you need to turn hubs on wheels in order to have 4 wheel drive work? If all you do to get in 4wd is move shifter, then you have automatic locking hubs. The clicking indicates that the hubs are not fully disingaging. To check, block rear wheels, jack front up, and turn tire. the axle should not be turning...if it is, hub is still ingaged....time for new hubs.....if hubs are bad, and you want to save money, you can purchase a set of manual hubs made by (WARN)...its more than half the cost, but you will have to turn hubs to lock and unlock manually. Note...you still need to use the gear selector to put and take out 4wd.

Jul 05, 2009 | 1999 Dodge Ram

1 Answer

4wd will not engage on 2002 gmc sierra 1500


try going into reverse for 10 feet then go to drive for 10 feet that might help if not it is to the wiring to you 4x4 engage system (wires to your wheel hub)

Jul 04, 2009 | 2002 GMC Sierra C/K1500

2 Answers

4 wheel drive (auto locking hubs) seems to be trying to engage.


I had the same thing happen. The automatic locking hubs are faulty, causing one or both hubs to try to engage or disengage onto the front driveshaft. This makes the clicking noise and loud clunking that you hear. You may notice your steering pulling to one side of the road,because one hub is locked in. Replace the automatic hubs with new ones, do not try to fix the old ones. I liked the
convience of automatic hubs but replaced mine with manual hubs, there just way more reliable.

Jun 04, 2009 | 1994 Ford F350 Crew Cab

2 Answers

Was driving onto a paved access road to beach. put switch in 4 hi about 40 yards from sand , increased speed to about 10 mph heard a sudden bang in front of truck. Truck came out of 4 wheel. 4 wheel lights...


Your automatic locking hubs are broken. Very common on ford trucks. The front hubs are geared with hard nylon gears, and are easily broken. If you replace your front hubs with "warn (name brand)" manual locking hubs, your issue will be resolved, and you won't have that issue again on your truck.

If you replace the hubs with manual locking hubs, you will have to stop, get out of the truck, and manually lock in your hubs every time you want to engage your 4 wheel drive. It beats getting stranded somewhere with no 4x4 at all; like you have now.

If you replace your hubs with the factory automatic locking hubs, the issue will return again in time.

May 26, 2009 | 2003 Ford F150 Regular Cab

1 Answer

2004 Ford F-150 extended cab FX4. 4WD problem


Your front hubs are automatic locking hubs, and the gears are hard nylon. These hubs break very easily, therefore causing you to lose your front wheel drive in 4 high, or 4 low. If you replace the hubs with "WARN (name brand) " manual locking hubs, you will never have the issue again. Of course, you will have to get out of the truck and manually lock the hubs, but they are metal gears, and much more durable. I've personally seen the issue several times, and changing the hubs has resolved the issue every time.

May 01, 2009 | 2005 Ford F-150

1 Answer

Noise when engaging 4wd


I have had this problem and it could be one of three things, first the truck has automatic locking hubs, lack of lubrication to these hubs could cause them to make exessive noise while engaging. also you could need to lubricate your universal joins on your forward drive shaft. lastly my problem was abs wheel sensor actuator in drivers front hub had (internal part of hub looks like a large gear with teeth) had broken a gear off causing the hub to get wear in it making it clunk while engaging the four wheel drive.

Dec 20, 2008 | 2000 GMC Yukon

Not finding what you are looking for?
Cars & Trucks Logo

Related Topics:

60 people viewed this question

Ask a Question

Usually answered in minutes!

Top GMC Experts

yadayada
yadayada

Level 3 Expert

76846 Answers

Freddy

Level 3 Expert

1311 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22246 Answers

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

Answer questions

Manuals & User Guides

Loading...