Purchase inspection - How to test 4x4?

[02AutoWag]

I have never owned a 4x4. Can you guys educate me on the proper procedure for testing a 1988 truck that is equipped with 4x4?
Thank you.

 

[hesutton]

Nothing to fancy......just put the truck in 4x4 Hi and drive a bit and then try it in 4x4 low. See if there are any scary sights or sounds. I wouldn't drive over 35 in 4x4, but that's just me. By the way, it won't make sharp turns as well in 4x4, so don't freak.

Heath

 

[Mike]

Preferably test it on a dirt road somewhere as well. Dry pavement will tear the hell out of a transfer case.

 

[dakotajeep]

You are going to want to ensure that it is actually working. Just because it goes in 4x4 and the light is on is not proof enough. I have heard of guys not testing the 4x4 and finding out in the worst time that the 4x4 was INOP. So you are on the right track by asking!!!!

If you only have pavement to work on, place it in 4x4 and make a sharp turn, ensuring that you are going super slow, 5 mph or less for this initial test. Immediately you will feel the front end pulling/slight binding/hopping. As soon as you feel it stop turning. That is not the preferred method but works if you cant get off road.

Thad

 

[MIDNIGHT RIDER]

The absolute best test of the 4WD system is to get the front-end up on jack-stands, with the hubs UN-LOCKED, transfer-case in 2WD, both front wheels should rotate WITHOUT turning the axle-joints visible inside the knuckles.

Now grab the front drive-shaft; it should turn freely and rotate at least one of the axle-joints.

While under there, check the front drive-shaft U-joints and slip-yoke; while either is not a deal breaker, you can point out any problems to the seller and possibly get the price down.


Now, LOCK ONE hub; when you rotate that wheel, you should hear/feel the hub "click" into lock and the axle-joint on that side should also now turn with the rotations of the wheel; UNLOCK that hub and go to the other side, LOCK it and test as before.


Now, LOCK both hubs and turn the front drive-shaft; one or both wheels should turn with it; while turning the shaft, have someone hold the rotating wheel and the other should immediately start turning.



Now, shift into 4-HI and you should not be able to rotate the front shaft; do likewise in 4-LO.


Now, drive the truck into a place that it loses traction in 2WD, somewhere like a grassy hill-side, or maybe a shallow ditch; when it is definitely un-able to dig it's way out, then lock the hubs, shift into 4-LO, and it should walk out of there with ease; if so, the 4WD is probably okay.

 

[02AutoWag]

Thanks guys.

I've got an 3000lb aluminum jack rated for vehicles and am guessing that it will not cut it for these bigger trucks.

How high a jack/lift and what weight rating do I need for servicing an IDI 4x4?

 

[Russ]

Now, drive the truck into a place that it loses traction in 2WD, somewhere like a grassy hill-side, or maybe a shallow ditch; when it is definitely un-able to dig it's way out, then lock the hubs, shift into 4-LO, and it should walk out of there with ease; if so, the 4WD is probably okay.

The ONLY thing wrong with this is: if the 4x4 DOESN'T work, you now have a truck stuck in a ditch

I use a 8000 lbs jack from Sears. cost about $100 works great.

 

[Agnem]

If you want a hard core test, pull the rear driveshaft, and use it as a front wheel drive vehicle. Great way to examine your U-joints while your at it.

 

[MIDNIGHT RIDER]

How high a jack/lift and what weight rating do I need for servicing an IDI 4x4?

I prefer good old hydraulic bottle-jacks for lifting by the axle-housing, etc.

Anything in the 8-,10-,12-ton range will be more jack than you will ever need.

I like a minimum of two, plus a set of six-ton stands.

 

[kcw12]

well for me testing 4x4 its gravel rev up and side step, see if anything breaks, make sounds, or anything like that

 

[BigRigTech]

Find a big ole' mud hole and eye it up...If the current owner starts shaking his head and sweating the 4x4 gear doesn't work........Slow speed turns on pavement works good - if it's pulling up front the wheel will be hard to handle.