How to test 4x4 system?

[ONAGER]

is there a way to test the 4x4 system, or a way to tell if its working? i have a feeling mine is not.

i was pulling my utility trailer out of the back of my property where i keep it, has been pretty muddy recently. I had the truck in 4x4, the rear tires (tire really) was kicking up lots of mud. But the fronts weren't. I didn't get stuck, but i wanna make sure its working, and if not, how do i go about fixing it? i read they are controlled by vacuum?

at a minimum how do i go about testing it?

[duramaxthis]

put in 4x4 get on tar and crank all the way to the left or right, if it hops and tires chirp, it works if not it dont

[bulldog84]

Originally Posted by duramaxthis

put in 4x4 get on tar and crank all the way to the left or right, if it hops and tires chirp, it works if not it dont

Right on

[melmount]

did you get out and lock the hubs?

[Jarrod B]

heres what i did when i first found out. since im on a farm land, i went to a spot on grass. in 2x4 mode i floored the truck and back spins. got the base test done. then 4x4 and floored it. no different. locked the hubs then floored it again and took off. so thats when i first found out mine didnt work. its redneck but it worked for me.

[bigcountrysg]

Originally Posted by duramaxthis

put in 4x4 get on tar and crank all the way to the left or right, if it hops and tires chirp, it works if not it dont

Hold on, do you want someone to break there truck. Come on this is the worse idea I have ever heard.

Not only can you break the hubs, u-joints, axle shafts, t-case. You can cause damage to the transmission casing.


To properly test your 4wheeldrive. First off you want to inspect everything. Take the hubs off the truck, check out the seal for the vaccuum on the hub. Check the vaccuum hoses going to the hubs. Check the vaccuum pump. If you have electronic shift on the fly. Check to make sure your getting voltage to the motor. Make sure the motor is actually shifting into 4hi.

If everything checks out from your inspection. Then go find a dirt road. Put your truck in 4hi. Then hammer down the throttle. If it spins from the rear, your truck is not in 4wd. So stop put the truck in park. Manually lock the hubs in. Then hammer down and try again. If you are still spinning and not taking off. Your t-case is not shifting into 4wd or you have a problem in the T-case.

But what ever you do. Do not drive in 4wd on dry pavement.

[bulldog84]

Originally Posted by bigcountrysg

Hold on, do you want someone to break there truck. Come on this is the worse idea I have ever heard.

Not only can you break the hubs, u-joints, axle shafts, t-case. You can cause damage to the transmission casing.

IMO, its not like your romping on the go pedal when you do this. All you do is put it in 4wd, turn the steering wheel full lock, and release the brake (your idleing). You find out really quick. You'll feel it in the steering wheel. Plus if something does break, the first time you went mudding you would be stranded. I would wrather find out at at the house rather than far from home. I would wrather lock my 4wd in and idle rather than romping on the go pedal. Just my 2 cents.

[bas157]

Get all 4 wheels off the ground with some good strudy jackstands, put it in 4wd, start it up, put in gear and see if 2 or 4 wheels are turning?

[Jarrod B]

there is no weight on the front wheels. so it can turn but add weight to it and it is possible they will not turn due to not being fully engaged.

[Nonturbo]

Originally Posted by duramaxthis

put in 4x4 get on tar and crank all the way to the left or right, if it hops and tires chirp, it works if not it dont

Originally Posted by bigcountrysg

Hold on, do you want someone to break there truck. Come on this is the worse idea I have ever heard.

Not only can you break the hubs, u-joints, axle shafts, t-case. You can cause damage to the transmission casing.


To properly test your 4wheeldrive. First off you want to inspect everything. Take the hubs off the truck, check out the seal for the vaccuum on the hub. Check the vaccuum hoses going to the hubs. Check the vaccuum pump. If you have electronic shift on the fly. Check to make sure your getting voltage to the motor. Make sure the motor is actually shifting into 4hi.

If everything checks out from your inspection. Then go find a dirt road. Put your truck in 4hi. Then hammer down the throttle. If it spins from the rear, your truck is not in 4wd. So stop put the truck in park. Manually lock the hubs in. Then hammer down and try again. If you are still spinning and not taking off. Your t-case is not shifting into 4wd or you have a problem in the T-case.

But what ever you do. Do not drive in 4wd on dry pavement.